CS680 Resource Kit
Denver International Airport (DIA) Case
Table of Contents
DIA CHRONOLOGY .................................................................................................................................................2
DIA CALENDAR OF EVENTS.....................................................................................................................................2
DIA TIMELINE BY MONTH ......................................................................................................................................3
DIA TIMELINE BY YEAR ..........................................................................................................................................4
DIA STAKEHOLDER LIST ......................................................................................................................................5
DIA STAKEHOLDER DECISION TREES .............................................................................................................8
CITY OF DENVER MAYOR.........................................................................................................................................8
BAE PROJECT MANAGER ...................................................................................................................................... 14
UNITED AIRLINES PROJECT MANAGEMENT TEAM ............................................................................................... 14
WEB CONTENT ...................................................................................................................................................... 15
UNITED TO SIMPLIFY DENVER’S TROUBLED BAGGAGE PROJECT [1] .................................................................. 15
IT’S TOO LATE TO BAG DIA’S AUTOMATED LUGGAGE SYSTEM – NO MATTER HOW MANY SUITCASES IT EATS
[2] .......................................................................................................................................................................... 16
AIRPORT WOES A WAKE-UP CALL [3] ................................................................................................................. 18
A CASE NARRATIVE OF THE PROJECT PROBLEMS WITH THE DENVER AIRPORT BAGGAGE HANDLING SYSTEM
[4] .......................................................................................................................................................................... 20
CASE STUDY DEMO [5] ......................................................................................................................................... 22
NEW DENVER AIRPORT: IMPACT OF THE DELAYED BAGGAGE SYSTEM [6]......................................................... 28
SOFTWARE’S CHRONIC CRISIS [7] ........................................................................................................................ 31
SOFTWARE NEEDS ENGINEERING: A POSITION PAPER [8] ................................................................................. 32
DE-ESCALATING INFORMATION TECHNOLOGY PROJECTS: LESSONS FROM THE DENVER INTERNATIONAL
AIRPORT [9] .......................................................................................................................................................... 33
COMPANIES DON’T LEARN FROM PREVIOUS IT SNAFU’S [10] ............................................................................ 37
THE BAGGAGE SYSTEM AT DENVER: PROSPECTS AND LESSONS [11]................................................................... 39
A QUOTA BY ANY OTHER NAME: THE COST OF AFFIRMATIVE ACTION PROGRAMS IN THE CONSTRUCTION OF
DENVER INTERNATIONAL AIRPORT [12] .............................................................................................................. 43
DIA MARKS ANNIVERSARY [13] ........................................................................................................................... 46
ANALYSIS OF THE DENVER INTERNATIONAL AIRPORT BAGGAGE SYSTEM [14] .................................................. 48
AIRPORT 95: AUTOMATED BAGGAGE SYSTEM? [15] ............................................................................................ 54
ODL 121 SYSTEMS DESIGN COURSEWORK [16] .................................................................................................. 56
IS IT REALLY READY TO FLY? [17] ....................................................................................................................... 66
WEBLIOGRAPHY ................................................................................................................................................... 68
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Instructor: Dr. Walter Maner July 12, 2004
Student Team: Acuna, Ghosh-Dastidar, Joshi
CS680 Resource Kit
Denver International Airport (DIA) Case
DIA Chronology
DIA Calendar of Events
Date Year Activity
1988 Denver committed to building a basement area in which to house it
1988 Denver actually decides to move forward with an automated baggage system
1990 Brierer, Neidle, Patrone & Assoc recommend against automated system
1991 UA contracts with BAE to build a baggage system specifically for United.
1992 Jan 1992 Denver exectuted the contract to automate systems
1992 Apr 1992 BAE awarded $175.6MM contract to build the entire airport system.
1992 Apr 1992 BAE presents city of Denver with proposal to build "most complex" system.
1992 May 1992 Head of DIA project resigns
1992 May 1992 Design of UA baggage system frozen when Proj Mgmt Team assumes resp.
1992 Aug 1992 UA alters plans for bags changing planes, asks for major changes from BAE.
1992 Aug 1992 Continental asks automated sorting be added to basement at cost of $4.67 MM.
1992 Aug 1992 Additional ski claim and odd-size bag requirements are added to plans.
1992 Sep 1992 Continental requests new system be added to its west basement.
1992 Oct 1992 Chief Airport Engineer Walter Slinger dies.
1992 Two affirmative action programs administered at DIA are implemented.
1993 Jan 1993 Ski claim area shortened to 112 ft.
1993 Jan 1993 Maintenance tracks added to telecar system.
1993 Feb 1993 Mayor Webb delays scheduled Oct 1993 opening to Dec 19, 1993.
1993 Sep 1993 BAE' loses contract negotiations with Denver over system maintenance.
1993 Sep 1993 First test of automated baggage system; one month before scheduled opening.
1993 Sep 1993 The opening was again delayed until May 15, 1994.
1993 Oct 1993 Original, scheduled, opening of new airport - Oct 1993.
1993 Dec 1993 New opening date for DIA after missing first deadline; March 1994.
1994 Jan 1994 United requests changes to its odd-sized baggage inputs.
1994 Jan 1994 Trio of tests not reassuring; 32 bags moved from AA space at Concourse C.
1994,Feb 1994 Full-scale testing of completed network scheduled to begin mid-February
1994 Feb 1994 An alternative baggage handling system was expected to act on this date
1994 Mar 1994 The panic, drop-dead date for opening the new airport.
1994 Mar 1994 Test of baggage system yields "bags literally chewed up".
1994 Mar 1994 With the surge problem corrected, a second full system test took place
1994 Apr 1994 After the test, Mayor Webb delayed the test yet gain - this time indfinitely
1994 Jul 1994 Tests run on an isolated section of track in effort to test reliability of the telecars.
1994 Aug 1994 Announcement of construction of a back-up baggage system.
1994 Aug 1994 Mayor Webb notifies BAE of $12,000/day penalty for missing original due date.
1994 Sep 1994 BAE, United and Denver reach agreement to modify the baggage system.
1994 Sep 1994 BTR Plc, parent company of BAE, lends support.
1994 Sep 1994 PA Consultanting helps debug the baggage system
1994 Osaka's Dansai Intl Airport lost bags months after it opened due to mix-up
1995 Jan 1995 Following system tests, 10,000-bag run of substitute system takes place.
1995 Feb 1995 DIA officially opens on Feb 28, 1995, a delay of 16 months and cost of $5MMM
1995 Aug 1995 Agreement with BAE to complete automated baggage system for Concourse A
1995 Oct 1995 BAE system finally finished
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CS680 Resource Kit
Denver International Airport (DIA) Case
DIA Timeline by Month
Deploy m en t
Relea se
Fu ll sca le T est of Su bst it u t e Sy st em
Fu r t h er t est in g a n d debu g g in g
Isola t ed T est in g
Secon d Fu ll Sca le T est in g
Un it a n d Fu ll-Sca le T est in g
Ch a n g e Requ est
Redesig n a n d Im plem en t a t ion
A lt er n a t iv e ba g g a g e sy st em In st a lla t ion
Fir st t est
Redesig n a n d Im plem en t a t ion
Ma in t en a n ce T r a cks A dded
Ch a n g e Requ est
Im plem en t a t ion
Desig n
Pr oject Ha n dov er t o PMT
Pr oposa l Pr epa r a t ion
Con t r a ct Ex ecu t ion
0 5 10 15 20 25 30 35 40 45 50
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Instructor: Dr. Walter Maner July 12, 2004
Student Team: Acuna, Ghosh-Dastidar, Joshi
CS680 Resource Kit
Denver International Airport (DIA) Case
DIA Timeline by Year
DIA is most efficient cold weather airport in the US.
BAE system finally finished.
DIA officially opens on Feb 28, 1995; delay of 16 months.
Alternative baggage system tests begin.
Mayor Webb notifies BAE of late penalties.
Announcement of plans to build a back-up system.
Test of baggage system yields "bags literally chewed up".
The panic, drop-dead date for opening the new airport.
System tests not reassuring; only 32 bags moved.
New opening date after missing first deadline.
Original, scheduled, opening of new airport - Oct 1993.
DIA opening again delayed until May 15, 1994.
First test of baggage system; one month before opening.
BAE loses contract negotiation maint workers.
Mayor Webb delays Oct 1993 opening to Dec 1993.
Chief Airport Engineer Walter Slinger dies.
Significant changes are made to project scope.
BAE presents Denver with complex proposal.
BAE awarded contract to build the system.
Consultants recommend against automated system.
Denver commits to automated baggage system.
1987 1989 1991 1993 1995 1997
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Instructor: Dr. Walter Maner July 12, 2004
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CS680 Resource Kit
Denver International Airport (DIA) Case
DIA Stakeholder List
Type of
Row Stakeholder Name Stakeholder Description
Stakeholder
Group overseeing the ethical effort to include
Affirmative Action
1. Group of People women and minority owned firms in the
Council
construction of DIA.
Airline representatives who witnessed the failure of
2. Airline Representatives Group of People
the initial mock-up test at DIA.
Major US airline that uses the Denver airport; lost
3. American Airlines Corporation
bags during initial mock-up test.
System Analysts for he baggage system; analyzed the
4. Analysts Group of People
feasibility of a complex system in a very short time.
Apollo Reservation
5. Corporation One of United Airlines software application systems.
System
Aviation System
6. Corporation Golden, CO consulting firm.
Research Corp.
BAE Automated Firm that designed and implemented DIA baggage
7. Corporation
Systems system; formerly Boeing Airport Equipment.
BAE team that designed the DIA baggage handling
8. BAE Designers Group of People
system.
BAE team that installed the DIA baggage handling
9. BAE Installers Group of People
system.
Mgmt team at BAE; responsible for supervising
BAE Management
10. Group of People software development and communicating with the
Team
client.
BAE team that programmed the DIA baggage
11. BAE Programmers Group of People
handling system.
BAE Software Test
12. Group of People Engineers who did the software testing at the site.
Engineers
13. Boyd, Michael Person President, Aviation Systems Research.
Breirer, Neidle, Connecticut based consultants; recommended
14. Corporation
Patrone & Assoc. against such a baggage system in 1990.
Parent company of BAE; provided additional help to
15. BTR Plc. Of London Corporation
BAE.
16. Cochrane, Gene Person BAE Project Mgr (at one time).
17. Coller, Diane Person Denver Deputy Director of Aviation.
State housing DIA; residents helped pay for the new
18. Colorado, State of Geographic Area
DIA facility but won’t benefit from employment.
Competitors of BAE who bid for the DIA baggage
19. Competitors of BAE Corporation
system contract but lost.
Major US airline that uses the Denver airport; DIA
20. Continental Airlines Corporation
problems contributed to Continentals bankruptcy.
21. Cook, Barbara Media Writer, Airport magazine.
Dallas International Airport in Dallas; underwent mock-up test by BAE
22. Corporation
Airport systems.
23. De Long, James C. Person Denver Aviation Director.
24. Denver City Corporation City government of Denver; partially owns the
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Instructor: Dr. Walter Maner July 12, 2004
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CS680 Resource Kit
Denver International Airport (DIA) Case
Type of
Row Stakeholder Name Stakeholder Description
Stakeholder
Government baggage system problem.
Denver Intl Airport
25. Corporation The ―new‖ airport in Denver.
(DIA)
26. Denver Port Authority Corporation Government entity in charge of regulating airport.
Major US city housing DIA; residents helped pay for
27. Denver, City of Geographic Area the new DIA facility but won’t benefit from
employment.
The county housing DIA; residents helped pay for
28. Denver, County of Geographic Area the new DIA facility but won’t benefit from
employment.
29. Di Fonso, Gene Person BAE President.
30. Doughty, Ralph Person BAE VP Engineering.
31. Drinks, Ivan Person Director MIS, DIA and Stapleton Airports.
32. Eddy, Mark Media Denver Post staff writer.
Airport workers who interface with the baggage
33. Employees, DIA Group of People
system on a daily basis.
34. Evans, Ginger Person DIA Director of Engineering.
35. Executives, BTR Group of People Assisted in the design of the baggage system.
US Federal Government; wouldn’t allow DIA to
36. Federal Government Group of People
open until baggage system was operational.
Frankfurt Airport, Previous BAE client; a BAE success although that
37. Corporation
Germany baggage system was built on a much lower scale.
38. Frontier Airlines Corporation Low cost airline that uses the Denver airport.
39. Gamblin, Briggs Media Spokesman for Denver Mayor.
People intent on disrupting or abusing the system;
40. Hackers / Crackers Group of People
increased complexity of the security system.
Hardware Test
41. Group of People Tested the hardware installed at DIA.
Engineers
42. Hinson Person Not sure of role.
43. Hughes, David Media Writer, Aviation Week & Space Technology.
44. IBM Corporation Manufacturer of OS/2 software used on servers.
Independent industry newspaper published out of
45. Innerline Media Stapleton; investigated and reported the DIA
problem.
46. Jones, Capers Person Not sure of role.
47. Knill, Bernie Person Not sure of role.
48. Kwapniewski, Frank Person BAE Site Project Mgr.
His problem solving model was used to help solve
49. Laudon Person
the baggage handling problem.
Manufacturer of Windows software used by baggage
50. Microsoft Corporation
system.
Minority Business Group focused on advancing minority owned
51. Group of People
Enterprise (MBE) businesses.
52. Musgrave, Michael Person Denver Public Works Mgr.
53. Netframe Systems Corporation Manufacturer of servers used by BAE.
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Instructor: Dr. Walter Maner July 12, 2004
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CS680 Resource Kit
Denver International Airport (DIA) Case
Type of
Row Stakeholder Name Stakeholder Description
Stakeholder
Chairman of the Technology and Policy program at
54. Neufville, Richard de Person
MIT; instructor in airport systems planning.
Construction Mgr on alternate, conventional
55. O’Brien-Kreitzberg Person
baggage system.
56. PA Consulting Corporation British based consulting firm used to debug system.
Fare paying airline customers expecting to receive
57. Passengers, Airline Group of People
quality baggage handling service.
Ex-Mayor, city of Denver; replacing Stapleton
58. Pena, Frederico Person w/DIA his idea; later Secr. of Transportation under
Pres. Clinton.
59. Philp, John Person United Airlines spokesman; director public affairs.
60. Raima Corp. Corporation Manufacturer of database software used by BAE.
Maker of traditional tug & cart baggage systems
61. Rapistan Demag Corp. Corporation
located in Grand Rapids, MI.
62. Regulators Corporation Regulators of the airport / airline industry.
63. Rifkin, Glen Media Writer, Forbes magazine.
Writer, Aviation Week & Space Technology
64. Scott, William B. Media
magazine.
Chief Airport Engineer for city of Denver; died in
65. Slinger, Walter Person
1992; a strong proponent of the baggage system.
66. Snyder, Steve Person DIA spokesman.
67. Stapleton Intl Airport Corporation The ―old‖ airport in Denver.
People or institutions who invested equity into the
68. Stockholders Group of People DIA project; angry at elected officials as they now
face loss of equity.
69. Suppliers Corporation Suppliers for the baggage system.
Manufacturer of computers used by the baggage
70. Texas Microsystems Corporation
system.
Struck city of Denver over BAE contract
Union Labor,
71. Group of People negotiations; BAE lost maintenance contract over
Electricians
fight for low wages.
Struck city of Denver over BAE contract
Union Labor,
72. Group of People negotiations; BAE lost maintenance contract over
Millwrights
fight for low wages.
Major US airline that uses the Denver airport;
73. United Airlines Corporation
Denver’s largest airline carrier.
United’s information systems staff; tested the
74. United Airlines IS Staff Group of People
baggage system at DIA.
United Airlines Project United’s project mgmt team for the baggage system;
75. Group of People
Mgmt Team assumed responsibility for the system.
76. Van Zandt, Bruce Person DIA Operations Mgr for backbone communications.
77. Vista Corporation Corporation Manufacturer of database server hardware.
78. Webb, Wellington Person Mayor, City of Denver
Women’s Business Group focused on advancing female owned
79. Group of People
Enterprise (WBE) businesses.
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Instructor: Dr. Walter Maner July 12, 2004
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CS680 Resource Kit
Denver International Airport (DIA) Case
Decision Tree: DIA Case
DIA The Mayor of the City of Denver
Stakeholder: Stakeholder Decision Trees
Stakeholder Role: DIA Owner/Operator
in Role: Frederico Pena (#58) & Wellington
PersonsCity of Denver Mayor
Webb (#78)
Red dotted line is the actual path chosen by the Mayor. Consequence A-1-1
Stapleton ages gracefully. Capital projects are planned
and executed as needed. Transportation demands are
met. A very acceptable consequence.
Option A-1
Capital improvements
START Consequence A-1-2
to existing Stapleton
HERE Stapleton ages gracefully. Capital improvements
Airport.
executed as needed. However transportation demands
are not met. At some point, a new facility is needed. But,
this consequence provides the time to plan for that event.
Decision Point A An acceptable and expected consequence.
How do we
Improve airport
facilities for the
Denver area?
Consequence A-2-1
Begin a long term planning process to ensure a solid
Option A-2 design that will meet current and anticipated
Build a new Denver transportation needs for Denver and Colorado. Use A
International Airport proven technology with allowances made for new
and then, as required technology as is feasible. Prototype. A wise choice.
by law, close the old
Stapleton Airport.
Consequence A-2-2
Quickly devise a plan to build a new state of the art
airport that meets most anticipated needs. Use cutting B
edge technology where ever possible. Rely on qualified
opinions as opposed to doing actual prototyping. A poor
choice.
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CS680 Resource Kit
Denver International Airport (DIA) Case
Consequence B-1-1
Construction begins on new airport, as planned.
Option B-1 Construction is deliberate and executed
Begin construction on according to a master project plan. No change in
Decision Point B new airport. project scope. New airport delivered on time and
Once planning is on budget. A wise choice..
complete, decide
A whether or not to
begin
construction. Option B-2
Scrap plans for new Consequence B-2-1
airport. Continue to Stapleton ages gracefully. Capital projects
use old Stapleton are planned and executed as needed.
Airport until such time Transportation demands are met. A very
as the planning acceptable consequence.
process can begin
anew.
Consequence C-1-1
Problems, errors and delays in
Decision Point C Option C-1 construction can be expected. Add in C
Once planning is Begin construction on scope changes and no control over a
B complete, decide new airport. master project plan and disaster looms.
whether or not to Not a wise choice.
begin
construction.
Option C-2 Consequence C-2-1
Postpone plans to Begin a long term planning process to ensure a
build new airport. solid design that will meet current and
Revisit planning anticipated transportation needs for Denver and
process and take a Colorado. Use proven technology with
more measure look at allowances made for new technology as is
how best to proceed. feasible. Prototype. Continue to use Stapleton in
the meantime. A wise choice.
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CS680 Resource Kit
Denver International Airport (DIA) Case
Consequence D-1-1
Option D-1 Capital spending is stopped. Some penalties
Stop project. Return may be realized, perhaps avoided if a strong
to the drawing board. contract was negotiated. Stapleton serves
Use Stapleton Airport transportation needs until a better design can
until better plan of be put together. Good decision only in the
action is available. sense that the bleeding is stopped.
Option D-2
Ignore red flags and
warning sirens; full Consequence D-2-1
steam ahead;. Patch DIA was ultimately completed years after the
breaks as they occur. scheduled completion date, millions over
Do not revisit project budget and with long term negative effects
Decision Point D levied upon Denver residents in the form of
plan; allow changes to
Given the problems higher taxes and higher air fare out of DIA.
scope.
experienced to date, in Interestingly enough this is the actual path
particular with the chose by the Mayor and is fairly close to being
C automated baggage the worst possible outcome possible under any
system, decide whether given scenario.
to stop the project and
cut losses or continue.
Option D-3
Recognize red flags by
halting all changes to
scope. Revisit project Consequence D-2-3
plan and make serious Capital spending continues. A poor
attempt to recover lost design is being enabled that will cause
ground by future problems. Not necessarily a good
implementing only decision but somewhat better than the
what is necessary. actual decision that was taken by the
Mayor.
END
HERE
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CS680 Resource Kit
Denver International Airport (DIA) Case
BAE Project Manager
Decision making tree for BAE project manager
Start
Doing more Better idea
research before starting
Level: 1
Accepting Decline due to No
the contract inexperience responsibility
Consulting Better idea on
Brierer, Neidle, pros & cons
Patrone
Acceptance of Start working Proposal to build most
contract complex system ever Level: 2
Creating a very Trying to create a Proposal of creating a
complex system simpler system prototype and testing it
Complex project Greater probability Idea about the end product
started w.o experience of success and its functionality
Level: 3 Accelerating
construction timeline
Accelration of
timeline Asking for larger Building a Take time and do Staying with the
timeline prototype first more research estimated time
Not meeting the
quality standards Greater chance to
solve complexity
Better idea on
end system’s
behaviour Greater chance of Being able to work
success with the initial plan
Backup baggage
system frozen
Level: 4
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CS680 Resource Kit
Denver International Airport (DIA) Case
Back up baggage
system frozen
Freeze back up Keep back up Modification of Level: 4
system untill success present system to
found make the new
No back up if Safeguard Basic idea of starting
error found against failure pt, less expenditure
Adding Stick to the Less chance of
Level: 5 complexity initial plan confusion
Add More critical
complexity situation
Testing of system before
one month of shceduled Level: 6
openning
Quick testing Testing a Asking for
of system prototype more time
Failure of Lower loss and More time to
inappropriate idea about the prepare
product deficiency
Incorporating changes
and testing again and Level: 7
again
Bring changes Construct a Asking for Verifying the Collecting
and conduct traditional more time changes(reques feedbacks
multiple tests system so that before other ted) before before testing
airport can tests proceeding further
open
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CS680 Resource Kit
Denver International Airport (DIA) Case
Chances of Situations Greater chance Safeguard Better and user
failure in the stabilized, have of success friendly system
tests more time to
complete
Modify the sys System made
and complete it for concourse
Level: 8 for concourse A A
Making an agreement
for completing the Taking the Chances of
system for concourse project off until making a
A correction/provid flawless system
e traditional sys
as back up
Leave the Huge loss, bad
contract and reputation,
provide the legal problems
traditional sys
Seeking More
agreement for responsibility END
other concourses and pressure
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CS680 Resource Kit
Denver International Airport (DIA) Case
United Airlines Project Management Team
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CS680 Resource Kit
Denver International Airport (DIA) Case
Web Content
United to Simplify Denver’s Troubled Baggage Project [1]
United Air Lines has emerged as the systems integrator that will start fixing the computer problems in an
automated baggage system that is delaying the opening of the new Denver International Airport.
United, which will act as project manager, will revise the system based on its experience in baggage-
handling technology used at other airports. ``I'd say most of the problems are because of the complexity
of the system,'' said John Philp, director of public affairs at United in Denver. ``It's the software to a
degree, but also just the size of it,'' he said in reference to Denver International's 21-mile-long baggage
system.
United wants to simplify the system and reduce the work load on the individual computers that track
luggage on 4,000 one-bag carts. ``It is a terrific load for the computer to keep up with,'' Philp said. In
addition, two of United's information systems staffers will continue to work on interfaces between the
BAE system and United's Apollo reservation system. United IS staffers have been testing the Denver
baggage system since late last year, Philp said.
Stapleton, Denver's other airport, and Denver International share an IS staff. These people are involved in
repairing the baggage system but will run it once the bugs are worked out and it becomes operational,
according to Ivan Drinks, director of MIS for both airports.
How it works
The 18-person IS staff will support all airport systems once they come on-line, Drinks said. That includes
an IBM ES/9000 Model 150, three IBM AS/400s, the central NetFrame Systems, Inc. LAN server and
hundreds of PCs.
The BAE automated baggage system is based on PCs, proprietary applications software and a multitasking
operating system thought to be IBM's OS/2. The system is intended to speed turnaround time by routing
bags automatically among airlines.
A series of laser scanners route the baggage carts on underground tracks, directing each piece of baggage
by reading its bar-coded label. There is only one piece of luggage per cart. As many as 60 carts per second
are on a single track, but United plans to cut that to 30 per track.
An alternate, traditional baggage system, based on conveyor belts and baggage trucks, is already being
constructed for the city by Rapistan Demag Corp. in Grand Rapids., Mich., for about $50 million. It is
expected to act as a fallback plan that will allow the airport to open by Feb. 28.
Denver International's baggage system was modeled on an integrated system in Frankfurt. But
Frankfurt’s system uses conveyors to carry bags instead of the 4,000 PC-driven automated carts that are
supposed to ferry bags at Denver International. Now, United is suggesting additional tracks and fewer
carts per track. ``It's just like adding another lane onto a highway,'' Philp said.
Challenge: To run an airport on client/server technology connected by a single high-speed fiber-optic
network and integrate IBM mainframes as servers on that network.
Strategy: Most of Stapleton Airport's computer systems have already been moved to Denver
International. The plan is to cut over to the new airport's computer systems on opening day. Computers
that run both airports are in place at Denver International, as is most of the 18-person IS staff.
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CS680 Resource Kit
Denver International Airport (DIA) Case
It’s Too Late to Bag DIA’s Automated Luggage System – No Matter How
Many Suitcases It Eats [2]
One of the few undisputed facts about Denver International Airport is that the new automated baggage-
handling system must succeed. Should the computerized network fail, there's no backup.
Full-scale testing of the completed network isn't scheduled to begin until mid-February, when the linkup
of Designated Coded Vehicles (DCVs), tracks, hardware and electronics will be loaded with bags and
operated at full speed 24 hours a day until the airport opens. Or the system breaks down, whichever
comes first.
DIA's computerized network is designed to begin either curbside or at the ticket counter, where luggage is
"laser-tagged, put on a conveyor belt and moved into a track-mounted cart," explains Gene DiFonso,
spokesman for the system's Dallas-based manufacturer, BAE Automated Systems.
But when BAE tested the system at a mock-up at Dallas's international airport last year, it "ate the
luggage, an incident witnessed by numerous airline representatives from Denver," according to Innerline,
an independent industry newspaper published out of Stapleton.
The trio of tests wasn't particularly reassuring. On January 11, 32 bags were moved from the American
Airlines space at Concourse C, the concourse DIA has reserved for "all other" airlines besides Continental
and United, Denver's two primary carriers. According to DiFonso, one bag was lost on the simple circuit
but later recovered. That's a success rate of 96.8 percent--but multiply the failing 3.2 percent by tens of
thousands of bags per day and DIA could have major trouble.
A test of the Continental system at Concourse A on the same day ended almost as soon as it began, after
the electrical motors burned out.
The third test was conducted on January 18 at the United system on Concourse B. That trial ended when
"the system jammed," says DiFonso.
All three of the DIA tests were limited in scope; none attempted inter-airline or inter-concourse
connections. The carts weren't fully loaded. They weren't running at full speed. And they certainly weren't
running 24 hours a day.
BAE got the job at DIA even though Connecticut-based consultants Brieier Neidle Patrone and Associates
recommended against such a baggage system in 1990.
After analyzing cost, maintenance needs and reliability, the consultants made the following
recommendations to the city:
"We believe it is essential that the facilities be designed on the basis of an initial implementation of a tug-
and-cart system for Concourse C carriers and automated systems for Concourse A and B carriers
"The single bag DCV solution should not be furthered, we believed, because of throughput limitations,
development risk, competitive availability, etc."
In fact, the only system that carried "a high degree of development risk is the single bag Designated Coded
Vehicle System concept," the consultants warned, and specifically recommended against adopting such a
DCV system.
Nevertheless, that's what DIA has.
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Denver actually decided to go with the automated system--and committed to building a basement area in
which to house it--as early as 1988, two years before the consultants recommended against it, according to
city documents.
As a result, DIA has now put all of its luggage in the one DCV basket. Until the system starts performing
better, travelers might be wise to limit their luggage to carry-on.
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Airport Woes A Wake-Up Call [3]
More than three years have elapsed since Denver International Airport opened. In the decade of the
1990s, several other new "green field" airports have opened around the world. All have shared a common
problem -- high-tech collapses that cost millions of dollars, created tremendous public relations disasters
and inconvenienced tens of thousands of people.
DIA had grave difficulty getting its 26-mile, $218 million automated baggage system to work properly,
and after several opening dates were missed, opted for a tug-and-cart system as the primary system for
two of its concourses, and a backup system for its third. Three years after DIA opened, its automated
baggage system only serves Concourse B's outbound operations, though United Airlines plans to spend
another $22 million to upgrade it to handle inbound and transfer baggage. The underground train linking
the main terminal to the remote concourses has failed on occasion as well. It too, was designed without a
backup system.
But Denver was not alone in having critical systems fail shortly after it opened. At Osaka's Dansai
International Airport, the airport was filled with lost bags months after it opened in 1994 because of
confusion over the airport's three-letter code, KIX rather than OSA, the code for Osaka's original airport.
When Vancouver's new terminal opened in 1996, a year passed before the system allocating gates
communicated properly with the system displaying flight information.
The first problem that emerged when the new Kuala Lumpur International Airport opened June 30, 1998,
was that technicians unfamiliar with the new loading bridges were unable to connect them to aircraft. The
opening date had been set, and completion hurried, to meet the opening of the Commonwealth Games in
September 1998, and to upstage the opening of the new airport at Hong Kong.
A total airport management system was installed at Kuala Lumpur, with airport wide communications
and information technology, allowing airport tenants and operators to communicate and use information
from shared databases. But soon after opening, the $168 million central computer network crashed,
leaving thousands of travelers stranded. The central computer controlled everything from escalators to
flight information monitors. Ticketing had to be done manually. Communications lines broke down as did
mechanical baggage handling systems. Because there was no backup communications system, the staff
had to use cellular phones to communicate. For several days, flights were delayed, check-in counters had
long lines, and tons of perishable goods rotted. Another problem at the new airport has been a massive
infestation of rats. Pest exterminators were hired and hundreds of rats were killed. The fear was that the
rats might chew on critical computer cables, as well as frighten passengers.
At the new Hong Kong International Airport at Chek Lap Kok, what has been described as the "world's
most advanced communications galaxy," integrates various airport computer systems while allowing each
to stand alone as a separate computer system. Flight display information, security, telephone, baggage
handling, public address, building management, fire alarm, mobile radios, time generation and display all
are integrated. The problem is, when it breaks down, it breaks down on a massive scale.
The Hong Kong Air Cargo Terminal Ltd. (HACTL), long the industry's standard setter, was unable to cope
with an accelerated completion schedule and a computer system which went haywire. According to
HACTL managing director Anthony Charter, "We really had not foreseen the impact of building
contamination -- the dust on the 14,000 sensors and reflectors." The day after the new airport opened,
Charter announced, "With immediate effect, all freighter loads will be handled at Terminal 2 at Kai Tak. It
appears we have some sort of bug which is deleting records." Charter would later implicitly blame the
airport authority, saying, "The whole feeling we got throughout this project was the airport would open on
a certain date regardless of whether we were ready or not."
At each of these airports, the opening was marred by a collapse of essential systems. The fundamental
problem was not just stretching the technological envelope, for the more sophisticated the system, the
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more venues deep within the recesses of computer hardware and software for lapses and failure. The
problem was also in stretching the envelope without installing simpler, less-expensive back-up systems to
kick in when the primary systems fail. If anything should be a wake-up call to the Y2K problem, these
examples should be it.
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A Case Narrative of the Project Problems with the Denver Airport Baggage
Handling System [4]
Target Objectives of the DABHS
Improve ground efficiency.
Reduce close-out time for hub operations.
Decrease time-consuming manual sorting/handling.
Risks recognized early in the DABHS Project
Very large scale of the project.
Enormous complexity.
Newness of the technology.
Large number of entities to be served by the system.
The high degree of technical and project definition uncertainty.
Chronology
April 1992 BAE was awarded the $175.6 million contract top build the entire airport system.
Company officials hammered out a deal in three intense working sessions
April 1992 BAE systems presented the City of Denver with a proposal to develop ―the most complex
and automated [and integrated] baggage system ever built.
May 1992 15 May 1992 Design of the UA baggage handling system was frozen when Project
Management Team (PMT) assumed responsibility for the integrated baggage system.
May 1992 shortly after the baggage system negotiations began, the head of the DIA project resigned.
August 1992 (as an example) UA altered plans for a transfer system for bags changing planes,
requesting that BAE eliminate an entire loop of track from Concourse B. (they would
operate with one loop rather than two). This saved approximately $20 million, but
required a system redesign.
August 1992 additional ski-claim devices and odd-size baggage elevators added in four of the six
sections of the terminal, added $1.6 million to the cost of the system.
September Continental requested that automated baggage sorting systems be added to its west
1992 basement at a cost of $4.67 million. The ski claim area length was first changed from 94
feet to 127 feet.
October 1992 Chief Airport Engineer Walter Slinger died. He had been a strong proponent of the
baggage system and was a key player in the negotiations.
January 1993 this ski claim length was shortened to 112 feet! The first change added $295,800 The
second change subtracted $125,000
January 1993 maintenance tracks were added to permit the Telecars to be serviced without having to
lift them off the main tracks. This cost an additional $912,000.
February Mayor Webb delayed the scheduled October 1993 opening to December 19, 1993. Later
1993 this was put back to March 9, 1994. This became the panic drop-dead date.
September BAE’s contract negotiations with the City of Denver over maintenance of the system,
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1993 occasioned a 2-day strike of 300 millwrights that was joined by ~ 200 electricians. BAE
lost the maintenance contract because they intended to pay $12 per hour for jobs that
union wanted $20 per hour.
July 1994 Logplan isolated a loop of track that contained every feature of the automated baggage
system and intended to run it for an extended period to test the reliability of the Telecars.
August 1994 Announcement of construction of a back-up system.
August 1994 Mayor Webb notified BAE that they would have to pay $12,000-per-day penalty for not
implementing the baggage system by DIA’s original completion date.
Initial Start
Communication was a problem from the beginning channels between: (a) The City, (b) The
Project Management Team and (c) Consultants, were never well defined
The tracking system was a disaster. They tried to merge the different systems into one central
database structure. Everybody had their own and it took 3 years to get working.
Implementing an Integrated Baggage Handling System
BAE had installed Telecar (laser barcode readers and conveyor belt system) but never on the size
envisaged in the tender offer. DIA was going to need something much bigger.
BAE told UA that it would take at least a year to get the system up and running, but no one
wanted to hear that.
Formulating Intentions
Although an automated system was more expensive initially than simple tugs and baggage carts,
it was expected that it would reduce the manpower need ton distribute the baggage as required.
To prove the capability, BAE proposed to build a prototype automated baggage handling system
in a 50,000 sq. ft. warehouse near its manufacturing plant in Texas.
The prototype system convinced Chief Airport Engineer (Walter Slinger) that the automated
system would work.
A dilemma was approaching: The City wanted a fully integrated airport-wide system and they had
no acceptable proposal, but UA intended to proceed with their own system and let the rest of the
airport be equipped with something else.
BA arrived at the scene with fully designed specs, which obviously in the long run proved to be a
major planning error.
The City had fallen into a trap, which historically architects and engineers tend to fall into as they
severely underplay he importance and significance of some of the requirements of the baggage
handling system, that is:
arranging for the space into which it must fit,
accommodating the weight that it may impose on the building structure
the power that is required to run it
the ventilation and air conditioning that may be necessary to dissipate the heat that it
generates.
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Case Study Demo [5]
What information system problems are addressed in this case?
Problem analysis is the first step in Laudon's problem solving model. Once the problem is defined, the
perspective from which the situation is viewed is substantially narrowed (indeed, that is one of the
reasons you define the problem). Any situation has several ways that a problem can be defined, even the
case studies we use in this course can be viewed with different problem definitions. For example, for this
case study you could choose as the problem
Provide fast delivery of travelers' baggage between airplanes and baggage collection areas.
With such a problem definition, the baggage handling system developed by BAE would be the solution. If
you selected this as the problem definition, then the case study documentation would be very different
from what is published here. That doesn't make it wrong, just different.
For the purposes of demonstrating the case study approach, the information system problem is defined as
Denver International Airport's baggage handling system failed to operate as expected, delaying the
opening of the new airport. Specifically, the failures included
Power surges tripped circuit breakers, with the result that baggage handling motors quit
operating.
Speed at which baggage moved resulted in loss of control when bags were shunted to side
conveyors.
Bar codes showing baggage destination could not be read.
Decision Making
Would an IS solution improve the problem
This problem appears to be a political problem (asking for more than the current technology can
support) and a technical problem (engineering of the system is not adequate) as opposed to a IS
problem.
Solutions that are needed
Correct problem of "flying" baggage
Proposed solution: Construct a traditional baggage handling system so that the airport can open
as soon as possible. When enough of the problems associated with the automatic baggage
handling system are solved, implement it at a lower speed. Work on the remainder of the
problems over several years until the automatic baggage handling system can be operated at its
specified capacity without problems.
Correct problem of illegible bar code strips
Replace the bar-code creation equipment with equipment that produces bar-code labels that can
be read by the scanners.
Solutions that were demonstrated
Special power filters were installed to maintain an even power supply
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How does the problem and/or solution affect the goals of the organization?
This case study has a somewhat unique issue: which organization owns the problem? Organizations that
could own the problem are BAE, Denver city government, or the consortium of airlines that was the
general contractor for the baggage system.
However, all three organizations are affected the same way: the new Denver International Airport cannot
open until the baggage system functions properly, making it impossible for the organizations to achieve
their customer-service or profitability goals.
What are the factors of the problem
People
Organizational
Technology
Task environment
Management considerations
Listed below are the subcategories described by Laudon for the people component of a system. Issues with
probable relevance to the problem are listed under the appropriate subcategory with the second-level
bullets (open circles). Subcategories for which no relevant issues were identified in the case study
description (in the opinion of the instructor) have no issues listed below them. Identification of what
issues are relevant is dependent on the problem definition and the perspective of those doing the analysis.
Ergonomics
Employee evaluation and monitoring
Training
BAE installers were inexperienced with baggage handling system this large
Truncated training and testing period
Employee attitudes and involvement
Legal and regulatory compliance
Organizational considerations
Listed below are the subcategories described by Laudon for the organization component of a system.
Issues with probable relevance to the problem are listed under the appropriate subcategory with the
second-level bullets (open circles).
Culture
Assignment of blame seems to be a higher priority that resolution of problems.
Project Management
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o Denver city government failed to establish a project structure that ensured accountability.
One company builds the baggage system. The city owns the system. Another company
maintains the system. A consortium of airlines leases the system.
o BAE management planned poorly. BAE agreed an accelerated construction timeline
despite their lack of experience with the scale and complexity of this system.
o Budget overruns is symptomatic of poor management planning or control.
Politics
o A loser in the power struggle is assigned a key role in the implementation of the solution.
How enthusiastically committed would BAE be to the project under the circumstances?
BAE was underbid to construct and operate the baggage system. The successful bidder
then subcontracted the construction to BAE.
o Relationship between BAE and City of Denver is poor.
Bureaucracy
o Denver city officials made changes (as alleged by BAE) to the system despite their
agreement not to make changes. Processes either should have prevented changes or re-
estimated project timelines when changes were made.
o Denver city government processes did not order electrical filters on a timely basis, thus
delaying the opening of the airport.
o Information systems control, operations, and maintenance is subcontracted (outsourced)
to several organizations.
Technology considerations
Listed below are the subcategories described by Laudon for the technology component of a system. Issues
with probable relevance to the problem are listed under the appropriate subcategory with the second-level
bullets (open circles).
Hardware
o New and unproven baggage system technology
o Bar code labels are illegible and require baggage to be hand sorted
o First baggage system to transfer baggage between carts and conveyors "on the fly"
o Baggage misses conveyor belts and is damaged
o Large, highly complex system
Software
o Though the case study did not mention this as a factor, the software for this baggage
system is identified in the software-quality literature as a primary source for the
performance problems
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Telecommunications
o First baggage system controlled by client/server computer system
o First baggage system to use radio links for identifying location of baggage
Database
o Bar code label system used to link baggage to information about its destination
Task environment considerations
Listed below are the subcategories described by Laudon for the task-environment component of a system.
Issues with probable relevance to the problem are listed under the appropriate subcategory with the
second-level bullets (open circles).
Customers
o Travelers will be dissatisfied with delays or damaged luggage
o Airlines paying for much of the cost associated with the delay in airport opening
Competitors
Suppliers
Regulators
o Federal government would not allow the airport to open until a baggage handling system
was operational
o Threats of investigation
Stockholders
o Taxpayers might not re-elect elected officials because of the increased cost of the airport
and ineptitude of the officials
How is this problem and solution likely to change given anticipated developments in
technology within the next few years?
This is your chance to do some "out of the box" thinking. From what you know of technology trends, make
some predictions! The answer to this question is not usually in the case study.
Smart chips will become inexpensive enough that luggage tags can contain information that will
assist in routing luggage.
Problem Solving Case Study
A State-of-the-Art Airport Can't Get Off the Ground
Background
Denver's Stapleton Airport has been the sixth busiest airport in the United States, with 1,600 takeoffs and
landings per day. But the airport, built in the 1920s, was clearly no longer capable of meeting Denver's
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needs. Mayor Fredrico Peña (later Secretary of Transportation in the Clinton
administration) decided
that the airport needed to be replaced, and the project to build the Denver International Airport
began in the late 1980s.
As the first new major airport to be built since the Dallas-Fort Worth airport opened in 1974, Denver
International was clearly designed for the future. Its 53 square miles makes it the largest airport in the
United States. The voice and data networks for the airport campus are almost exclusively fiber optic and
can operate at 100 Mbps (megabits per second). An even higher-speed network— 2.4 Gbps (gigabits per
second)— has been installed specifically for use by video security cameras, allowing the airlines to monitor
such areas as gates and jet ways. The airport traffic control tower is the tallest in the United States and
contains the most modern electronic technology. It is supported by not just one, but two surface detection
systems (which locate the plane positions while they are on the ground); three systems are planned for the
future. The airport construction plans were approved at a budgeted cost of a little over $2 billion and with
a completion date of October 1993.
Luggage system
Each functional unit of the airport, including facilities, security, heating and ventilation, and the airline
operations themselves, has its own computer systems operated by subcontractors. One of the airport's
most advanced features is its automated luggage handling system, which is designed to carry 700 bags per
minute (the modern United Airlines system at San Francisco airport handles only 100 per minute). The
system is controlled by a network of desktop computers that processes millions of messages per second.
All bags are tagged with a bar-coded route/destination label and then placed on a conveyor belt, much as
they are in other airports. Every bag is automatically placed in a fiberglass baggage cart, and the bar-
coded tag is read by a laser device. Each baggage cart has a small radio transmitter mounted on it. Every
150 to 200 feet the cart transmits to the computer system its location and the bar-code information on the
luggage it is carrying. When a bag reaches the conveyor belt that will carry it to the appropriate airplane or
baggage claim area, the cart flips the bag onto that conveyor belt. The belts and carts are propelled by over
10,000 motors and travel at 17 miles per hour. The designers claim that the system is so fast that in many
cases the bag will reach the airplane before the passenger reaches the boarding gate. Like the other
distributed systems serving the airport, the baggage system operates outside the control of the airport's
information systems department
Denver's system is the first automated baggage system to serve an entire airport. It is also the first where
baggage carts do not stop, but only slow down to drop off and pick up bags; the first to be run by
networked desktop computers rather than a mainframe; the first to use radio links; and the first to handle
oversize bags (in Denver, usually for skis). The system can quickly reroute bags for last-minute gate
changes or send them to special inspection stations.
Troubles developed prior to the scheduled opening of the airport. Budget overruns exceeded $1 billion.
When problems with the baggage-handling system appeared, the opening of the airport was delayed until
March 1994. The system, which is owned by the city of Denver, was described as "the spine of the airport."
Government officials insisted that the baggage-handling system be operable before the airport would be
allowed to open. The system was being built by BAE Automated Systems of Carrollton, Texas. BAE
president Gene DiFonso wanted his company to be hired directly by the city to construct the system, but
instead BAE became a subcontractor of a maintenance company that was hired by a consortium of airlines
leasing the system from the Denver city government. BAE also lost its bid to operate and maintain the
system once it was built. BAE had built similar systems elsewhere, but they were all much smaller and
operated at one-third the speed. When construction of the baggage system began in mid-1992, airport
construction work was already well under way, and DiFonso was forced to accept an accelerated schedule.
He agreed to the tight schedule but only with the provision that no changes be made to the plans. DiFonso
claims that in the following months city officials repeatedly made changes. City officials deny the charge.
The baggage system problems did not surface until the first test in September 1993, just a month before
the airport was initially scheduled to open. Tested under realistic conditions, the system generated
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unexpected power surges that tripped the electrical circuit breakers, automatically shutting down the
motors. The city of Denver, United Airlines, and BAE all hired their own consultants. Special filters that
could maintain an even power supply were needed to repair the problem, but the city delayed in ordering
them. As a result, the original airport opening was postponed until March 1994.
Although electrical glitches were the main reason for postponing the opening of the airport at that time,
DiFonso said that too little testing had been done to establish the reliability of the system. On March 9,
1994, with the surge problem corrected, a second full system test took place with hordes of reporters,
photographers, and TV crews in attendance. When the system ran at full speed, bags flew everywhere, and
many fell and broke open. About two-thirds of the bags were shunted to the hand-sorting area because the
bar codes on the tags were too smudged to be read by the computer. The test was a dramatic failure, and
the opening was again postponed.
Other problems added to the complications caused by the snarled baggage system. Television monitors
that flash flight information were not ready. A sign directing passengers to the baggage claim area led
instead to a concrete wall. In the meantime, the new airport cost Denver $500,000 each day it remained
closed.
Conclusion
The airport did not open officially until February 28, 1995. The delay of 16 months and the need to correct
its baggage-handling problems put overall costs at $5 billion, nearly $3 billion more than originally
projected. Airport authorities decided to operate the baggage system on a small scale at first, moving only
30 to 60 bags per minute, well below the rate of 700 bags per minute estimated for a fully operational
system.
A year later, the Denver airport reported very few problems, emerging as the most efficient cold-weather
airport in the United States. It ranks only after Honolulu and Las Vegas, Nevada, for the fewest flight
delays. Statistics show that baggage loss and damage in Denver falls well below the national average.
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New Denver Airport: Impact of the Delayed Baggage System [6]
DIA'S AUTOMATED BAGGAGE HANDLING SYSTEM
Chapter 3
The automated baggage handling system, with a contract price of $193 million, will be one of the largest
and most sophisticated systems of its type in the world. It was designed to provide the high-speed transfer
of baggage to and from aircraft, thereby facilitating quick turnaround times for aircraft and improved
services to passengers. Baggage will travel between the terminal and concourses through interconnecting
tunnels. The most distant concourse is located about a mile from the terminal.
Even after modifications are complete, the automated baggage handling system will have two main
components: (1) high-speed, bag-carrying telecarts mounted on tracks and (2) connecting conveyor belts
to load and off-load baggage. The tracks are suspended from the basement ceilings of the terminal and
concourses. Electric motors and synchronous drives move the telecarts along the tracks at varying speeds.
Photocells and radio frequency reading devices direct each telecart to the right location. In total, the
original system included over 17 miles of track; 5.5 miles of conveyors; 4,000 telecarts; 5,000 electric
motors; 2,700 photocells; 59 laser bar code reader arrays; 311 radio frequency readers; and over 150
computers, workstations, and communication servers. The automated system was originally designed to
carry up to 70 bags per minute to and from the baggage check-in and baggage claim areas at speeds of up
to 24 miles per hour. This would allow the airlines to receive checked baggage at their aircraft within 20
minutes.
PROBLEMS WITH DIA'S AUTOMATED BAGGAGE HANDLING SYSTEM
Chapter 3:1
Significant mechanical and software problems have plagued the automated baggage handling system. In
tests of the system, bags were mis-loaded, were misrouted, or fell out of telecarts, causing the system to
jam. Video cameras were installed at several known trouble spots to document problems, such as the
following:
The baggage system continued to unload bags even though they were jammed on the conveyor
belt. This problem occurred because the photo eye at this location could not detect the pile of bags
on the belt and hence could not signal the system to stop.
The baggage system loaded bags into telecarts that were already full. Hence, some bags fell onto
the tracks, again causing the telecarts to jam. This problem occurred because the system had lost
track of which telecarts were loaded or unloaded during a previous jam. When the system came
back on-line, it failed to show that the telecarts were loaded.
The timing between the conveyor belts and the moving telecarts was not properly synchronized,
causing bags to fall between the conveyor belt and the telecarts. The bags became wedged under
the telecarts. This occurred because telecarts were bumping into each other near the load point.
Although the contractor--BAE Automated Systems Incorporated--believes that these problems have been
resolved, other problems remain. To resolve these problems and make the system operational, a number
of critical tasks must be completed. A recent BAE system status report listed 72 hardware, software, and
testing activities that must be completed, such as the following:
The telecarts' front bumpers have to be replaced so that they will not slip under the back bumpers
when telecarts collide. These collisions have caused telecarts to lock together.
Additional track, synchronous drives, and related software changes must be installed to improve
"empty car management," that is, allocating the correct number of telecarts to specific locations at
appropriate times.
BAE and City of Denver officials recognize that the system's testing might uncover additional problems.
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MODIFICATIONS TO DIA'S BAGGAGE HANDLING SYSTEM
Chapter 3:2
Because of continuing problems with the automated system, the City decided to build an alternative (i.e.,
conventional) baggage handling system and make substantial modifications to the automated system. The
alternative system will use conveyor belts, tugs, and carts to move bags to and from the terminal and
concourses. The alternative system will be the primary system until the automated system comes on-line.
Once the automated system is operational, the alternative system will serve as a backup system if the
automated system malfunctions.
The automated system also will undergo substantial modifications. The City and United entered into an
agreement that allows United to contract directly with BAE to modify portions of the automated system to
provide a separate outbound automated baggage system for United by February 28, 1995. These
modifications include changing the routing of the telecarts so that more of them serve United at
Concourse B. The inbound portions will not be completed until later. The agreement also includes a
requirement for BAE to complete an automated baggage system for Concourse A by August 31, 1995. The
City will evaluate the need for an automated system for Concourse C carriers within 6 months after the
airport opens.
BAE will be paid $17.5 million on February 28, 1995, assuming that the system is operational, and the
remainder after the system is substantially completed. If the automated system is not operational by
opening day, United will be served by the conventional baggage system.
REMAINING UNCERTAINTIES
Chapter 3:3
A number of outstanding, unanswered questions surround the baggage handling system. Among the
remaining uncertainties are the following:
Timing. The automated system is undergoing modifications, and construction of the alternative system is
just getting under way. Both systems must still be tested before the airport can open. Prior tests have not
gone well.
Performance. The original automated system was designed to transport outbound baggage from the
terminal to the aircraft within 20 minutes. It is not yet known whether the modified automated system
will meet design standards. The City estimates that bags can be delivered using the alternative system in
20 to 25 minutes. United and carriers on Concourse C have expressed concern about whether the
conventional system can deliver bags in the times estimated by the airport system. United believes that
using the alternative system may take up to 50 minutes to deliver bags to aircraft at DIA's most remote
gates. Airlines at Concourse C believe that it will take 27 to 31 minutes to deliver bags using this system.
Final system configuration. It has not been decided whether Concourse C will eventually be
reconnected to the automated system. This could result in lower levels of baggage service to airlines and
their passengers on Concourse C.
Resource requirements. The conventional system is much more labor-intensive than the automated
system. United told us that it currently has about 1,100 employees working the baggage system at SIA; an
additional 600 people would be needed to handle baggage using DIA's alternative system. The usefulness
of the conventional tug-and-cart operation as a backup system after the automated system becomes
operational is also in question because of the additional standby employees required.
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Unresolved claims. The final cost of the baggage system is uncertain because of the potential for
litigation after the baggage system is completed. The City has not paid BAE $22 million of the $193
million contract for the automated baggage system. On September 29, 1994, BAE, United, and the City
reached an agreement for modifying the automated baggage system. The agreement calls for the City to
pay BAE $17.75 million of the unpaid $22 million but reserves the rights of both parties to assert claims
for alleged damages. They agreed to attempt to resolve their claims through mediation, but if
unsuccessful, they agreed to file any unresolved claims in court.
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Software’s Chronic Crisis [7]
Denver's new international air port was to be the pride of the Rockies, a wonder of modern engineering.
Twice the size of Manhattan, 10 times the breadth of Heathrow, the airport is big enough to land three jets
simultaneously-in bad weather. Even more impressive than its girth is the airport's subterranean
baggage-handling system. Tearing like intelligent coal-mine cars along 21 miles of steel track, 4,000
independent "telecars" route and deliver luggage between the counters, gates and claim areas of 20
different airlines. A central nervous system of some 100 computers networked to one another and to
5,000 electric eyes, 400 radio receivers and 56 bar-code scanners orchestrates the safe and timely arrival
of every valise and ski bag.
At least that is the plan. For nine months, this Gulliver has been held captive by Lilliputians-errors in the
software that controls its automated baggage system. Scheduled for takeoff by last Halloween, the
airport's grand opening was postponed until December to allow BAE Automated Systems time to flush the
gremlins out of its $193-million system. December yielded to March.
To veteran software developers, the Denver debacle is notable only for its visibility. Studies have shown
that for every six new large-scale software systems that are put into operation, two others are canceled.
The average software development project overshoots its schedule by half; larger projects generally do
worse. And some three quarters of all large systems are "operating failures" that either do not function as
intended or are not used at all.
The art of programming has taken 50 years of continual refinement to reach this stage. By the time it
reached 25, the difficulties of building big software loomed so large that in the autumn of 1968 the NATO
Science Committee convened some 50 top programmers, computer scientists and captains of industry to
plot a course out of what had come to be known as the software crisis. Although the experts could not
contrive a road map to guide the industry toward firmer ground, they did coin a name for that distant
goal: software engineering, now defined formally as "the application of a systematic, disciplined,
quantifiable approach to the development, operation and maintenance of software."
A quarter of a century later software engineering remains a term of aspiration. The vast majority of
computer code is still handcrafted from raw programming languages by artisans using techniques they
neither measure nor are able to repeat consistently. "It's like musket making was before Eli Whitney," says
Brad J. Cox, a professor at George Mason University. "Before the industrial revolution, there was a non-
specialized approach to manufacturing goods that involved very little interchangeability and a maximum
of craftsmanship. If we are ever going to lick this software crisis, we're going to have to stop this hand-to-
mouth, every-programmer-builds-everything-from-the-ground-up, pre-industrial approach." The picture
is not entirely bleak. Intuition is slowly yielding to analysis as programmers begin using quantitative
measurements of the quality of the software they produce to improve the way they produce it. The
mathematical foundations of programming are solidifying as researchers work on ways of expressing
program designs in algebraic forms that make it easier to avoid serious mistakes. Academic computer
scientists are starting to address their failure to produce a solid corps of software professionals. Perhaps
most important, many in the industry are turning their attention toward inventing the technology and
market structures needed to support interchangeable, reusable software parts.
"Unfortunately, the industry does not uniformly apply that which is well known best practice," laments
Larry E. Druffel, director of Carnegie Mellon University's Software Engineering Institute. In fact, a
research innovation typically requires 18 years to wend its way into the repertoire of standard
programming techniques. By combining their efforts, academia, industry and government may be able to
hoist software development to the level of an industrial-age engineering discipline within the decade. If
they come up short, society's headlong rush into the information age will be halting and unpredictable at
best.
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Software Needs Engineering: A Position Paper [8]
Many travelers have experienced the chaos airports and their logistics can inflict on their personal plans
when it comes to baggage handling. However disastrous such an experience may have been, it is most
certainly exceeded by what the system of Denver International Airport was capable of, or, was not capable
of. The project to build an automatic baggage handling system was added in 1992 as an additional aspect
of building the new Denver International Airport (DIA), which is twice the size of Manhattan and 10 times
London’s Heathrow airport. The DIA baggage system is a subterranean baggage handling system
consisting of 21 miles of steel track connecting all the terminals facilities designed to house 20 airlines.
Baggage is automatically routed on these tracks in 4,000 independent carts, controlled by more than 100
networked computers and countless sensors and radio communicators. At the heart of the operations is a
purpose built software system monitoring and controlling the movement of the baggage in the carts.
Unfortunately industry experience shows that such projects to develop and install large software systems
are on average 50% late, with corresponding over-expenditure and serious teething problems. even after
delivery, and the DIA baggage system was no exception. Problems with the software system delayed the
opening of the airport from October 1993 in various stages until February 1995 . in the meantime a
conventional system for baggage handling had been constructed as backup. As late as 1996, with the
automated system in operation, there were still considerable problems to be resolved.
What went wrong?
Whilst there were some mechanical problems and some problems with sensors, the real problems were
with the control software of the baggage system. These problems were not simple programming defects
that could remedy in a rather straightforward manner. No, these problems were built in right from the
start through inadequate handling of the requirements the software system was supposed to fulfill. In
particular, permitting changes to the requirements and the specification in a less than controlled manner
compounded this. It is not possible to attribute the failure of a software project to just one single cause,
but lack of discipline in software management processes permitted the risks to grow.
SOFTWARE SYSTEM FAILURE’S MAJORCAUSES
Robert Glass [1] categorizes major causes of software system failures as:
1. Project objectives not fully specified
2. Bad planning and estimating
3. Technology new to the organization
4. Inadequate (or missing) project management method
5. Insufficient senior staff on the team
6. Poor performance by suppliers of hardware/software
7. (Other) performance or efficiency problems
None of the above categories is really technological at heart; they are all related to software management,
i.e. the lack of the application of proper engineering management to the software part of a larger project,
or the lack of risk management in technology adoption
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De-Escalating Information Technology Projects: Lessons From the Denver
International Airport [9]
Project failure in the information technology area is a costly problem and troubled projects are not
uncommon. In many cases, these projects seem to take on a life of their own, continuing to absorb
valuable resources, while failing to deliver any real business value.
While prior research has shown that managers can easily become locked into a cycle of escalating
commitment to a failing course of action, there has been comparatively little research on de-escalation, or
the process of breaking such a cycle. Through de-escalation, troubled projects may be successfully turned
around or sensibly abandoned.
Through an intensive longitudinal case study of the IT-based baggage handling system at Denver
International Airport (DIA), we gathered qualitative data on the de-escalation of commitment to a failing
course of action, allowing us to inductively develop a model of the de-escalation process as it unfolded at
DIA. The model reveals de-escalation as a four-stage process: (1) problem recognition, (2) re-examination
of prior course of action, (3) search for alternative course of action, and (4) implementing an exit strategy.
Implications of this model for both research and practice are discussed.
From a practical standpoint, it is important to understand how projects that become locked into losing
situations can be successfully terminated (if necessary) or redirected (if possible), a process we call de-
escalation.
While an analysis of what went wrong at DIA (i.e., the escalation of commitment to build an airport-wide
computerized baggage handling system) would be interesting in itself, this is not our aim here. The
primary purpose of this study was to gain a better understanding of the de-escalation process, whereby
commitment to the airport wide computerized baggage handling system was reduced and an alternative
baggage handling system was devised so that the airport could be opened. Accordingly, the focus of our
research was to understand, from a process perspective, how and why de-escalation occurs.
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THE MODEL THAT EMERGED
Phase 1 of the model involves recognizing the problem. Nothing of consequence can happen until
decision-makers in positions of responsibility and authority recognize that there is indeed a problem. In
the DIA case, this phase was characterized by recognizing the negative feedback that surrounded the
automated baggage system, as well as responding to external pressures. Phase 2 involves re-examining
the previously chosen course of action. In the DIA case, this re-examination involved clarifying the
magnitude of the problem with the previously chosen course of action and fundamentally redefining the
problem. Phase 3 involves searching for an alternative course of action. In the DIA case, the search
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involved identifying and legitimizing an alternative course of action, along with managing impressions so
as to allow Mayor Webb and the city of Denver to justify the new course of action. Phase 4 involves
implementing the exit strategy. In the DIA case, this involved appealing to stakeholders to reach a
mutually agreeable implementation strategy and de-institutionalizing the project.
While the decisions that we documented are obviously case specific, we believe that the phases that were
observed, as well as the events or triggers, may have some generalizability to other cases of de-escalation.
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Once a problem has been identified, the challenge is to ascertain the extent of the problem and to
reexamine the viability of the previously chosen course of action in light of this new information. Here,
the manager should not hesitate to conduct a full-blown review of the project. Forming an in-house task
force to examine the problem and to begin formulating 31 solutions will go a long way toward containing
the damage. In the search for alternative solutions, the manager must try to reframe the problem in a way
that unfreezes commitment to the failing course of action. The root cause of the business problem (for
which the IT project was the proposed solutions) must be examined so that alternative means of
addressing the problem can be identified. It may be that the business problem can be addressed in an
entirely different way. Re-conceptualizing the problem space in this manner requires thinking outside the
box. Remember that legitimizing a new course of action may be facilitated if it has an outside stamp of
approval from an independent third party. In the final phase of de-escalation, managers should conduct a
stakeholder analysis, paying careful consideration to both internal and external constituencies. Asking the
question: ―Who will be disenfranchised or likely to exhibit resistance if I attempt to implement the
proposed exit strategy?‖ Direct appeals to internal and external constituencies may be needed to negotiate
and implement an exit strategy that will be found acceptable by all parties.
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Companies Don’t Learn From Previous IT Snafu’s [10]
Computer projects have failed for as long as there have been computers. But now that most companies are
only as stable as their bits and bytes, the consequences of information technology screw-ups aren't easily
disguised - they show up in earnings reports.
When IT goes bad, high-growth rocket ships like Oxford Health Plans Inc. and Ben & Jerry's Homemade
Inc. report their first-ever financial losses. Others crater and run for bankruptcy protection, as did drug
distribution giant FoxMeyer Corp.
In a Computerworld study of multimillion-dollar IT disasters, the following two not-so-surprising themes
emerged:
• User companies like FoxMeyer often file tough-to-win lawsuits against the vendors or
consultants involved. Nonetheless, collectively, users rarely seem to learn much from the episodes
or apply the lessons to future projects.
• All of the botched projects in Computerworld's Top 10 disasters list were big and richly complex;
many were the toughest IT projects the users had ever tried. Five were hideously difficult
enterprise resources planning (ERP) system implementations.
Root Causes Remain the Same
The root causes of IT failures haven't changed a bit over the years.
Miscommunication, hazy goals, "scope creep," inept leadership, pitiful project management - you've
heard, if not heeded, it all before.
"We may be neck-deep in the New Economy and Internet time, but you still have the same factors and the
same failings," said Bruce Webster, a director at PricewaterhouseCoopers in Washington.
Webster recently studied 120 IT lawsuits filed since 1976, and he said he's convinced that most flops could
be avoided if people simply knew the time-honored best practices of systems development.
"I don't know how many IT managers, team leaders, directors and CIO’s have actually sat down and read
The Mythical Man-Month, The Psychology of Computer Programming and Death March," he said,
referring to three books that amount to the software development canon. "The causes of disasters are all
well documented. They're fundamental."
Still, warning lights are easy to overlook when the whole room is spinning.
"There's a natural tendency to get overly committed to something, especially when there are no clear
signals telling you are off course," said Mark Keil, an associate professor at Georgia State University in
Atlanta.
The infamously buggy baggage-handling system at the Denver International Airport is one case that
offered unambiguous proof of technology glitches: shredded luggage.
But tests of most questionable IT projects don't yield such graphic evidence.
In large systems integration or ERP deals, "there's no torn suitcase sitting at your feet to wake you up,"
said Keil, who has studied IT disasters for nine years. "So it's a lot easier to delude yourself into thinking
things aren't that bad."
Project Euthanasia
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Euthanasia for the project might be the best course, but people often have too much heart and money
invested to end it.
One technique for preventing a disaster is to add some humility to the endeavor. Invite a third party to
review your work - a reliable consultant, an academic or a buddy CIO.
An outsider can "walk into the project setting for 20 minutes, talk to a few people and come to the
conclusion that things have run amok. But people inside may not even be aware," Keil said.
Greyhound Lines Inc. in Dallas, for example, seemingly didn't know anything was wrong with its new
reservations and logistics system - until it went live and 12% of its customers went away mad in one
month.
Though specific individuals might learn from their own mistakes, those lessons aren't transferred to any
collective IT consciousness.
"The people with that [failure] experience aren't always the people in authority the next time that
situation arises," observed Kevin Hickey, a former head of IT at Trumbull, Conn.-based Oxford Health
Plans Inc. "The fact is, hubris will always be with us."
And then there's what Webster calls "the thermocline of truth." Swimmers know that lake water separates
into warm and cold horizontal bands. The area between is a thermocline.
In IT groups, everyone below Webster's "thermocline of truth" knows the project is sinking, while
everyone above it thinks things are fine. Senior executives can be oblivious. They aren't involved enough,
they don't want to have to face a failure, or underlings are afraid to tell them, he explained.
"You can see that persist almost until the point where the project is supposed to be delivered," he said.
"Then, suddenly, it's, 'What do you mean this will take another six months?' "
That was part of the sorry plight of Fort Worth, Texas-based AMR Corp.'s Confirm reservations system.
Confirm managers are even said to have orchestrated a cover-up.
Overall, IT culture is such that problems, especially expensive ones (which hold the most valuable
lessons), are hidden. Programmers write around buggy code rather than tear it apart. Managers revise
project specifications to reflect what they did instead of what they should have done. Senior IT leaders
neglect to tell their bosses the bad news.
Most companies are too embarrassed to analyze their failures, said Effy Oz, an associate professor of
management and IT at Pennsylvania State University in Great Valley.
"People will say, 'There's no time, and we're not paid to have these discussions,' " Oz said. "The CEO has to
be a very confident person to say, 'These things happen. Let's learn from it.' "
The average loss in an abandoned project is $4.2 million, according to Oz. The blowups in
Computerworld's top 10 list cost much more than that. And, if history is any indication, they will happen
again.
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The Baggage System at Denver: Prospects and Lessons [11]
Background
A mechanized baggage system is at the heart of the New Denver Airport, as for all major new airports. In
the case of Denver, this was to be something unique: the "Integrated Automated Baggage Handling
System", originally designed to distribute all baggage --including transfers -- automatically between
check-in, the aircraft and pick-up on arrival. Unfortunately, massive problems plagued this automated
baggage system. (See Henderson, 1994, for example.) Consequently, the New Denver Airport did not open
in October 1993 as scheduled. After missing later opening dates in April and May 1994, the Airport seems
-- as of January -- likely to be open in March 1995. The delay would then be around 16 months.
This delay costs the owners a lot. The interest on their bonded debt exceeded US $ 271 million for the
single year of 1994 (Deloitte and Touche, 1994). The costs of maintaining the new airport are extra. A
commonly accepted estimate of their costs of delay, endorsed verbally by officials in Denver, has been US
$ 33 million a month. By March 1995, the delays may thus have cost them around US $ 500 million. A
year after the original opening date for the airport, the City and County of Denver borrowed a previously
unscheduled US $ 257 million (City and County of Denver, 1994b). This delay is also expensive for the
airlines. Both the airport owners and the airlines will also suffer losses to the extent that the automated
baggage system does not deliver the productivity and efficiency that they had bargained for.
Design of the Automated Baggage System The fully automated baggage system originally planned for the
New Denver Airport was unique in its complexity, its novel technology, and its anticipated capacity. It was
designed to deliver each bag, including transfers, individually from check-in or the unloading of the
aircraft to the outward bound aircraft or baggage reclaim. The delivery mechanism consists of about 9 km.
(5.5 miles) of conveyors and over 27 km. (17 miles) of track on which circulate 4000 individual, radio-
controlled carts, the so-called "destination coded vehicles" or "DCVs" (US Government Accounting Office,
1994). The capacity of each track was supposed to be 60 DCVs per minute, one a second.
The essential layout of the automated baggage system at Denver is that conveyor belts feed the central
network of DCVs. The bags do not flow continuously from the conveyor belts, however, as they do in
traditional systems. Each bag must independently be placed on its exclusive cart, and thus the delivery of
the bags from the conveyor belts must be carefully controlled. Furthermore, the conveyor belt can only
advance when there is an empty cart onto which the leading bag on the conveyor belt can be placed. The
speed at which the conveyor belts can advance -- and thus the performance of the entire system --
depends on the rate of delivery of empty carts to each conveyor belt. This is a crucial point, at the root of
the deeper difficulties with the original design. The destination of each bag and its individual cart is
defined by bar-coded labels, and transmitted by radio to tags (the "radio frequency identification" or "rf
ids") on the constantly moving vehicles. The operation of these vehicles is to be entirely controlled by a
network of about 150 computers (Myerson, 1994; US Government Accounting Office, 1994).
Speed in handling baggage is critical to achieving acceptable boarding and transfer times at Denver, since
the distances are much greater those at other airports. The space between the midfield concourses
provides for two taxiways (one is standard) between the tails of the aircraft parked at the concourses, and
the terminal building in which passengers check-in and pick up their bags is separated from the first
concourse by an office block, a garage, and the Customs and Immigration (FIS) facilities. Being late, the
design was thus subject to two important constraints. First, the geometry was tight. The automated
system had to fit within the confines of the airport passenger buildings and the underground tunnel
connecting the concourses and the terminal; in many instances it was shoe-horned in at considerable
inconvenience. Second, the schedule was tight. The system was to be implemented within 21 months,
since Denver executed the contract only in January 1992. This schedule precluded extensive simulation or
physical testing of the full design.
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Remarkably, the design of the fully automated baggage system at Denver did not include a meaningful
backup system. The planners provided neither a fleet of tugs and carts that could cope with the level of
baggage expected, nor even access roads between the check-in facilities and the aircraft.
Obvious Problems
Highly visible mechanical problems have plagued the automated baggage system at Denver. As shown by
television and widely reported in the trade and popular press, the baggage carts have jammed in the
tracks, misaligned with the conveyor belts feeding the bags, and mutilated and lost bags (Flynn, 1994;
Henderson, 1994; Myerson, 1994). To deal with these difficulties, the contractors are installing additional
equipment. For example, more laser readers will reduce the probability of misreading the destination of
each bag. More controllers will slow down the carts, reduce misalignments with the conveyors feeding
bags, and minimize the momentum that tossed bags off the carts. Overall, solutions to the mechanical
problems come at the price of increased costs, reduced performance, and lower cost-effectiveness of the
system.
Deeper Problem of Reliable Delivery
The blatant difficulties with the automated baggage system designed for the New Denver Airport are
almost certainly only the tip of the iceberg. There is a deeper, fundamental problem associated with all
complex systems of handling baggage, cargo or materials. The more extensive and long-term difficulty is
that of "reliable delivery times". The fully automated system may never be able to deliver bags consistently
within the times and at the capacity originally promised. This difficulty is a consequence of the extreme
complexity of its design combined with the variability of the loads.
The entire system consists of well over a hundred waiting lines that feed into each other. For example,
bags can only be unloaded from the aircraft and put into the system when the unloading conveyor belt is
moving, this belt will only advance when there are empty carts on which to place bags, empty carts will
only arrive after they have deposited their previous loads and have proceeded through the system, and so
on. In short it is a complicated "cascade of queues".
The patterns of loads on the system are highly variable. These depend on the season, the time of day, the
type of aircraft at each gate, the number of passengers on these aircraft, the percentage traveling with skis,
etc., etc. There may be over a thousand reasonable scenarios! Managing a complex network of interacting,
fully loaded queues efficiently for any single scenario is complicated. Managing these flows under all the
realistic scenarios is exponentially more difficult. Learning how to do this appears to be a major, long-
term research project.
Causes of Reliable Delivery Problem
Enormous Increase in Complexity:
The development of a fully integrated, automated baggage system, such as the one originally designed for
Denver, represents an enormous technological leap over current practice. No airline, for example, has
used a fully automated system to deliver "hot" or time sensitive baggage for passengers transferring
between aircraft in 45 minutes or less. The individual elements of the baggage system at the New Denver
Airport have each, separately and on a much smaller scale, been used successfully -- but they have not
functioned together in such a large system. This enormous increase in complexity is the root of the
problem. It is a truism in systems design that as you increase the complexity, the difficulties in making the
system work increase "exponentially". If the system is 10 times as complex, the difficulties could be 100
times as great. The fully automated system at the New Denver Airport is far more complex than
predecessor systems. It features about 12 times as many carts as in the existing comparable systems in
San Francisco or Atlanta, which are also very much simpler in layout and the number of connections. The
speed of its carts is about 10 times as great as on conventional conveyor belts.
Difficulties in "Line Balancing":
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The complexity of a fully automated system leads to tremendous difficulties in trying to achieve reliable
delivery times. To guarantee acceptable delivery times under all circumstances in a network of queues
such as at Denver, it is crucial to control the capacity of the system so that all lines of flow have balanced
service. This is the "line balancing" problem.
Conceptually, the problem of "line balancing" is simple, once one thinks about it. As the name suggests,
the issue is to provide equally good service to all lines, in the case of Denver to provide sufficient empty
carts to each of the conveyor belts that feed bags onto the system of carts. The point of this is to avoid
situations where some lines get little or no service, to avoid the possibility that some connections simply
do not function. This kind of failure can easily happen in any system where a common artery serves many
demands.
The solution to the line-balancing problem is to control the "empties", to make sure that there is enough
space available, at the right time, to all users of the system. Specifically for the fully automated baggage
system originally planned for Denver, the crux of the solution is to devise control systems that will deliver
enough empty carts to all the conveyor belts delivering bags to the system.
Solving the line balancing problem efficiently can be very difficult. This is especially true for complicated
systems such as Denver, with highly variable flows on close to 100 independent lines of access. This is
where the complexity of the fully automated baggage system originally designed for Denver has a major
impact. The difficulty in solving the line balancing problem increases exponentially with the number of
lines or queues requiring service.
Short Term Fixes
Complementary, Backup System
Reduction in Complexity and Loads
Long Term Solutions
Efficient solutions require time: An efficient control system for any automated baggage system is likely to
take a long time to develop successfully. Rapid efforts seem bound to fail. In particular for Denver, it is
difficult to have confidence that the system as originally planned would ever be able to guarantee the
adequate delivery of empty carts, at the proper time and proper place (Knill, 1994). The problem is
difficult to solve in practice. Getting a control system to deal effectively with the line balancing problem
requires extensive testing for the specific loads prevailing at a site. At Frankfurt am Main, getting the
automated baggage system in Terminal 1 to work reasonably properly reportedly took several years of
operation – and this work does not apply easily to Denver since the German system and pattern of loads
are different. By comparison, testing of the full Denver system under realistic loads had not taken place as
of December 1994. As of that date, only the much simpler, significantly reconfigured system serving just
one mid-field concourse had been successfully tested, and that only for outbound baggage (Hensel Phelps
Construction Company, 1994).
The problem should be checked out in advance by computer simulation. Doing this properly requires a
simulation of essentially every bag, over an extended period, under hundreds if not thousands of
scenarios. This is an arduous task for a system as complicated as Denver, requiring many months just to
organize, let alone to run through powerful computers (Breier Neidle Patrone, 1990). The theory for
solving the line-balancing problem has furthermore not been worked out. It seems clear however that the
analytic solutions will be complex and require great sophistication. Practical solutions have had to be
worked out situation by situation according to the specific patterns of activity. A major technical review of
Denver's fully automated baggage system could not find evidence of appropriate solutions to its line
balancing problem:
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The line-balancing problem is compounded by a general ignorance or disregard for its existence. Even
knowledgeable designers and operators of automated systems seem not to focus on this issue. For
example, the installers of the fully automated baggage system at Denver seem to have discovered the line-
balancing problem six months after the original opening date for the system. A site manager giving the
tour of the system in July 1994 referred to "car starving" (because conveyor belts are "starved" of empty
carts onto which they could deposit their bags when the lines are not properly balanced) and described it
as a novel phenomenon that they had just started to work on! ...
Extensive Detailed Work
Achieving reliable delivery times also requires very high mechanical and computer reliability. Not only
must the system be able to be in operation a very high percentage of the time (which has been the
immediate focus of attention at Denver), but it must also operate accurately. However, sufficient accuracy
is not easy to achieve, either in reading information, or in managing it in the computer. To deal with the
inevitable misreads, the most important thing is to have a backup system. This is standard, but costs
money and time, and degrades performance. The complementary solution is training of personnel and
continuous improvement of the system -- this comes with experience and may take years to acquire.
Managing the information accurately is also difficult. The database needs to track tens of thousands of
bags, going to hundreds of destinations, all in real time. The problem is further complicated at Denver
because it uses a distributed system of about 150 computers. The software must, in addition to the usual
error checking codes that guard against electrical disturbances in the communications, have multiple
levels of redundancy and be able to recover from errors very rapidly. Getting this right can take many
expensive programmers a lot of time (Gibbs, 1994).
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A Quota by Any Other Name: The Cost of Affirmative Action Programs in
the Construction of Denver International Airport [12]
After months of delay and massive cost overruns, Denver International Airport (DIA) has found its
opening indefinitely postponed. One of the most important reasons for the delay has been the affirmative
action policies imposed on firms in construction of DIA. But for those affirmative action policies, Denver
International might well have opened "on time and under budget." This Issue Paper details the massive
costs which have been inflicted on the people of Denver, and the city's reputation, through policies of
racial discrimination.
No-one knows exactly how many tens of millions of dollars have been lost as a result of the Webb
administration's decision to reject BAE as the baggage system operator because, apparently, BAE pledged
merely to fulfill, and not exceed, the Webb/Pena racial quotas at the airport.
Significant as the baggage system fiasco costs are, they are only one part of the gigantic waste of public
funds caused by the Webb/Pena racial quotas. This study provides a conceptual framework for measuring
the costs of affirmative action, some estimates of these costs in construction of DIA, and some policy
implications.
WHEN DOES AN AFFIRMATIVE ACTION "GOAL" BECOME A QUOTA?
Some persons claim that no quotas were imposed at DIA because the affirmative action "goals" are
voluntary. It is true that affirmative action programs at the federal, state, and local level are stated in
terms of "goals" in contracting work to minority owned enterprises (MBE's) and female owned enterprises
(WBE's). If contracts are awarded to MBE's and WBE's only when they submit low bids, then there are no
quotas, and no additional construction costs incurred. But, if contractors who fail to meet affirmative
action "goals" in their bids are not awarded contracts, then the goals become quotas. When contracts are
set aside for MBE’s and WBE’s even when these firms are not low bidders the costs of construction are
increased by these set asides.
The argument that affirmative action "goals" for contracts at DIA are voluntary is not supported by the
data. The appendix to this study compiles evidence on the two affirmative action programs administered
at DIA by the Denver Mayor's Office of Contract Compliance in 1992. The federal government
implemented an affirmative action program in the award of both construction and professional services
contracts. The federal program makes no distinction between MBE’s and WBE’s, but rather lumps the two
together into a disadvantaged business enterprise (DBE) program. Of the 16 federal government contracts
awarded under this program none were significantly below the "goals" for DBE's, and a number of
contracts significantly exceeded those "goals."
WHAT WAS THE COST OF SET ASIDES IN CONSTRUCTING DIA?
Estimates of the cost of set asides varies considerably. At least seven bids were rejected by the Pena/Webb
administrations because the low bidder did not meet the "goals" for subcontracting to minority firms.
Those contracts were then set aside to higher cost bidders who met the affirmative action "goals." When
the city awarded those seven contracts to higher bidders who met affirmative action "goals," the increase
in construction costs was $3 million.
WHAT WAS THE COMPLIANCE COST OF AFFIRMATIVE ACTION PROGRAMS IN THE
CONSTRUCTION OF DIA?
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The cost of set asides is only the tip of the iceberg in estimating the cost of affirmative action programs in
public works construction projects such as DIA. All firms at DIA incurred labor and capital costs to
remain in compliance with affirmative action regulations and recent studies provide a basis for estimating
these compliance costs.
Research by the Center for the Study of American Business at Washington University estimates that for
every dollar spent on regulatory enforcement, about 20 dollars is spent for compliance costs in the private
sector. Compliance with federal affirmative action regulations increased federal contractors' costs by an
average 6.5%. In 1991, $211 billion was spent by the federal government on contracts with non-
government entities. The additional cost to private sector firms to comply with federal affirmative action
regulations in the award of these contracts is estimated at about $13 billion.
The total contract dollars for construction of DIA is now estimated at $3.2 billion, although that figure
will surely be higher as a result of the delays in completing construction. If we apply the 6.5% figure to the
estimated cost of construction of $3.2 billion, compliance costs for these firms is estimated at $208
million.
WHAT WAS THE COST OF ADMINISTERING AFFIRMATIVE ACTION PROGRAMS IN
CONSTRUCTING DIA?
Costs are also incurred in the public sector to administer the affirmative action programs. Of the total
$425 million spent by the federal government for civil rights oversight in 1991, about $303 million was
allocated for enforcement of affirmative action laws affecting the private sector. In addition to federal
dollars, state and local monies are also spent to enforce affirmative action regulations. The Denver
Mayor's Office of Contract Compliance, which administers these affirmative action programs, had a
budget of $540,000 last year.
WHAT WERE THE SOCIAL COSTS OF AFFIRMATIVE ACTION PROGRAMS IN THE
CONSTRUCTION OF DIA?
Society incurs costs over and above the cost to individual firms in complying with affirmative action
regulations. These social costs are difficult to quantify, but this does not mean that social costs are any less
"real" than those estimated above. Social costs are incurred due to delays in completion of construction
of the airport. These costs are incurred not only by construction firms, but also by airlines,
concessionaires, and passengers. The City of Denver has floated $3 billion in bonds to finance the
construction of the airport. In the absence of delays those funds would be available in either the public or
private sector rather than being tied up in airport construction. The City of Denver must spend $18.8
million per month in interest payments on the bonds sold to finance airport construction. With no
definite date set for the opening of DIA, it is highly probable that these interest costs alone will cumulate
to over $100 million.
A SOLUTION
During the late 19th century, big-city political bosses would hand out public funds on the basis of
ethnicity, giving a certain percentage of government contracts to the Irish, a certain percentage to the
Italians, and so forth. Progressive reformers combated discrimination and fraud in public works by
requiring that contracts be awarded to low bidders. The low-bid rule enabled all firms, including minority
owned firms, to compete for contracts based upon quality and price.
But in late 20th century Denver, the city is governed like late 19th century Chicago, as politicians hand out
hundreds of millions of public dollars on the basis of what favored group the recipient belongs to, rather
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than the basis of merit. To add insult to injury, the administrators of Denver's modern spoils system wrap
themselves in a sanctimonious mantle of "fairness." The impact of a pork-barrel quota system such as the
one at DIA has been to reduce competition and enable special interests to transfer wealth through the
public sector. Much of the burden of these wealth transfers falls on the least advantaged members of the
society.
Colorado's taxpayers and contractors could use some genuine fairness, and the best way to get fairness is
through re-instituting the Progressive-era reform of the lowest bidder system. Awarding public works
contracts to the lowest qualified bidder is the only way to ensure true equality. The lowest bidder rule
enables all firms, including minority owned firms, to compete for the award of these contracts based on
their quality and efficiency. In the award of construction contracts, such as those at DIA this would mean:
1)no race/gender barriers; 2) no race/gender preferences; 3)no race/gender subcontracting quotas; and 4)
no race/gender set asides.
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DIA Marks Anniversary [13]
Don Mills first traveled through Denver International Airport on the second day it was open. Since then,
he has used DIA several times a month. After five years, he doesn't have any complaints. "The airport is
one of the nicest that I travel to. It is so new and so spacious," Mills said. When DIA opened in 1995, there
were a host of questions and concerns surrounding what it cost to build, delays in its opening, potential
travel costs because of those issues, and the airport's proximity to Denver and travel time to DIA's remote
location. In the past five years, the number of flights and passengers have increased, and skepticism
among users has declined. And airport officials say they expect those trends only to continue. In 1999, 38
million passengers used DIA, up 7 million from the 31 million passengers who used the airport in 1995.
The $5 billion airport was $3.2 billion over budget and opened 16 months behind schedule. BAE
Automated Systems' failure to finish the automated baggage system was responsible for two of the four
delayed openings and prompted the city to build a manual baggage system so the airport could open.
BAE's system finally was finished in October 1995. Customers still complain about how long it takes to
get to the airport. "People are generally happy with the airport, just not the location," Travel Ease owner
Dan Hildbrand said.
The airport is on 25 miles northeast of downtown Denver. It is about an hour drive from Boulder, whereas
the old airport, Stapleton International Airport, was about a 30-minute drive. Mills, a consultant for
Design Alliance of Boulder, said getting to DIA is easier than getting to other airports he routinely travels
through. Usually he takes the bus. "They really have done a great job in making options for travel," Mills
said.
Steve Snyder, a spokesman for DIA, said he hears the complaints about the long drive, but because of the
growth in the Denver Metro area, the airport is not as remote as it was when it was first built. "Being out
here like this is really a big advantage because we have a lot of room to grow," Snyder said. According to
Snyder, other cities, such as Atlanta, Chicago and New York, want to expand their airports, but they do
not have the land to permit such growth. Snyder said the airport can handle up to 50 million passengers a
year within the current facilities and has the room to expand concourses and runways to accommodate up
to 100 million passengers a year.
"We have the room to grow and the capacity to handle basically twice what we're handling now," Snyder
said.
Flights have increased about the same rate as passengers. In 1999, there were 500,000 flights at DIA, up
from 473,000 in 1998. Mills said the lack of crowds and his ease of getting through DIA probably is
related to the fact that the airport is operating below capacity. He is not sure what will happen as traffic at
DIA intensifies. Passengers continue to be concerned about the lack of nonstop, direct international
flights, as well as a higher cost because of the lack of competition among airlines, travel experts say.
Currently, DIA offers direct flights to Canada, Mexico and London. Travel Ease's Hildbrand says DIA lags
behind most major airports. For example, he said: "Las Vegas has more international, nonstop direct
flights than DIA."
Snyder says one of the goals for the future is to increase the number of such flights, especially to European
countries. High prices are another complaint heard among DIA travelers. Part of that, officials said, is
there are few lower cost airlines providing service through the airport. Hildbrand calls DIA "one of the
most expensive airports to fly out of in the country,"
But Snyder says DIA's average cost is only slightly higher than the national average. In 1998, for instance,
DIA flights were 15 cents per mile traveled, while the national average was 14 cents per mile traveled. The
dominant airline is United, which uses the large Concourse B and has begun expanding into Concourse A.
Frontier Airlines is one of the handful of lower cost airlines at DIA. That has helped it carve out a niche in
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Denver and the airline has made DIA one of its hubs. Currently Frontier leases four gates, but starting
Wednesday it will lease nine.
"A lot of critics said that no discount carrier would be able to succeed here, and I think Frontier has
proven a lot of people wrong on that," Snyder said.
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Analysis of the Denver International Airport Baggage System [14]
FUNCTIONALITY OF ORIGINAL BAE DESIGN
Savior of Modern Flying
When the automated baggage system design for the Denver International Airport was introduced, it was
hailed as the savior of modern airport design. Designed by BAE Automated Systems of Carrollton, Texas
(previously Boeing Airport Equipment), it allows airport planners to design airports of larger size, using
narrow corridors and tunnels for baggage where no tug and cart system can run. Furthermore, it requires
none of the manual labor personnel, and can be used as easily in pinpointing the location of baggage as in
moving it. The design truly fits its description as the world's most advanced baggage handling system. It is
intended to run faster and more reliable than traditional technology. Its automation is so thorough, that
in most cases, baggage offloaded from an aircraft doesn't see a human until it meets with its owner at the
baggage claim. The system's speed outperforms even the airport's high speed trains. Flyers never have to
hover around the baggage terminal waiting for their baggage as with traditional systems, because their
baggage arrives at the claim before they do. On departure, their baggage arrives at the aircraft before they
do.
High Speed
Denver's baggage system design calls for replacing the traditional slow conveyor belts with telecars that
roll freely on underground tracks at more than three times the speed. A telecar that is loading baggage
rolls at 4.5 miles per hour. A telecar that is unloading its baggage rolls at 8.5 miles per hour. A telecar in
transit rolls at a fast 19 miles per hour. Each track can handle 60 telecars per minute. It is the
combination of using Denver International Airport's underground tunnel network and swift speeds that
allows all baggage to move between any concourse and the airport terminal in less than nine minutes. In
United's concourse B, transfer baggage moves between any two gates in under six minutes. According to
Briggs Gamblin, a spokesman for Denver Mayor Wellington Webb, the system's high speed nature is
intended to shave minutes off the turnaround time of each arriving or departing flight.
Components
The BAE design includes a number of high-tech components. It calls for 300 486-class computers
distributed in eight control rooms, a Raima Corp. database running on a Netframe Systems fault-tolerant
NF250 server, a high-speed fiber-optic Ethernet network, 14 million feet of wiring, 56 laser arrays, 400
frequency readers, 22 miles of track, 6 miles of conveyor belts, 3,100 standard telecars, 450 oversized
telecars, 10,000 motors, and 92 PLC's to control motors and track switches. With so much equipment
serving such a large area, the Denver International Airport's baggage system is the world's largest. "This
project is of the same magnitude as the Panama Canal or the English Channel Tunnel," said Mayor Webb.
The system's total cost is $193 million dollars.
Baggage Handling Process
Because of the revolutionary automated baggage system, the process of handling baggage is unique at
Denver International Airport. At check-in, agents stick glue-backed bar code labels on baggage,
identifying the bag's owner, flight number, final destination, and intermediate connections and airlines.
Instead of printed bar code tags, United's portion of the system uses photocells that serve the same
purpose. The check-in agent then puts the bag on a conveyor belt. Since no baggage can move without a
telecar holding it, a system exists for dealing with telecar allocation. Empty car management software is
the heart of the allocation system, dispatching empty telecars to where the tracking computers anticipate
they will be needed. The computers sense changes in demand by measuring the flow of passengers
throughout the airport. During peak times, all 3,550 telecars are available for moving baggage.
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Tracking Baggage
As the telecars roll, the tracking computers monitor each of the system's thousands of radio transponders
which emit millions of messages per second. The computers must also track all gate assignments so that
the telecars can be re-routed if a change is made. The tracking computers can also re-route bags to special
inspection stations, including one that is bomb proof. The same computers must keep track of
obstructions or failures as well, so that telecars can automatically detour around a stalled vehicle or
jammed track.
Oversized Baggage
In addition to standard-sized baggage, the system can also accommodate nonstandard-sized baggage on
oversized telecars that measure 6.5 feet long by 4 feet wide. The oversized telecars are essentially double-
length standard telecars. They are meant for non-standard size baggage which in Denver typically tends to
be skis and golf bags. The oversized telecars navigate through twists, turns, and switches the same way the
standard telecars do.
Security
Impressing, the system can work in full capacity for 18 hours every day at a 99.5 percent efficiency rate.
Two counter-circulating closed-loop tracks with multiple routing connections provide for future
expansion and add redundancy to guard against unanticipated problems. To protect against malice that
could theoretically shut down the whole airport by halting the flow of baggage, tight computer security is
built into the baggage system. The system has strict access privileges for workers, and its command center
is well guarded and locked behind steel doors. Despite BAE's conflicting advice, the entire automated
baggage system is run by DIA's information systems staff of 18 employees, according to Ivan Drinks,
director of MIS for both Stapleton and Denver International Airport.
Object-Oriented Architecture
Fortunately, the automated baggage handling system illustrates the principle of object oriented design
beautifully. It sends messages to objects (the telecars), which respond by returning other objects (baggage
and empty telecars) to the sender. Its real-time software was programmed in OS/2 and intended to run on
OS/2 version 2.0. Decentralized computing allows the baggage system to operate independently of the
airport's information systems department. The only dependence within the system involves coordination
with the airlines
PROBLEMS AND SOLUTIONS
Denver's Baggage Problems
The Denver International Airport's automated baggage system experienced such horrific problems that
most with an opinion on the matter are thrilled to elaborate on their sense of what went wrong. It seemed
that what could go wrong, did go wrong. Even the signs directing passengers to the baggage claim led to a
concrete wall. Unfortunately, analyzing the true nature of the system's faults is not an easy task. Problems
were so widespread, that possibly no small number of reasons can alone account for the chaotic
performance in the system's early testing. Insight can be found in examining the accounts of some key
people who were involved in the baggage project.
Expert Opinions
In response to criticism after the third opening delay, BAE president Gene DiFonso explained, "We simply
ran out of test time" because of changes requested by the airlines, problems "working around other
vendors," and failures in the airport's electrical power supply. Denver aviation director James C. DeLong
maintained that baggage software glitches and electrical supply harmonics were late and unexpected
obstacles to opening the Denver International Airport. According to David Hughes of Aviation Week &
Space Technology, contributing factors to the baggage system's problems included concrete mechanical,
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electrical, and software flaws. William B. Scott of Aviation Week & Space Technology believed that the
system's troubles originated in more fundamental miscalculations such as overall system complexity,
underestimation of tasks, a steady stream of changes requested by both airline and Denver officials, and
politics.
Technologically Advanced
The BAE design is technologically advanced. According to Richard de Neufville, it is not the next
generation of baggage system, it is more like a jump from third to fifth or sixth generation. Unfortunately,
BAE misused its technological advantage by expecting spectacular performance from the system
components, and not allowing them a proper margin of error. The components were expected to perform
to their highest theoretical capabilities. Bruce Van Zandt, operations manager for the backbone
communications network at Denver International Airport stated, "The system pushed the envelope of
technology. The components that were put into the system were run right to the limit of what they were
designed for." When any of the components failed in this respect, others failed as well due to the system's
inherently tight coupling.
Planning
BAE, DiFonso said, was originally contracted by United in the fall of 1991 to build a baggage system
specifically for United Airlines at the new Denver International Airport. The airline, he said, was
concerned that after several years into the project, the city still had not contracted for a baggage system.
Indeed, Denver's baggage system design was an afterthought to the construction of the airport. The BAE
system was detailed well after construction of Denver International Airport had begun. When
construction of the automated baggage system finally began, problems arose due to the constraints of the
buildings and structures which would contain the baggage system's tracks and other components.
Unfortunately, the system had to fit into the underground tunnels and available space given the
challenging and unrelated Denver International Airport construction plans. Tight geometry resulted in
additional construction difficulties. Telecars had to make unreasonably sharp turns on tracks shoehorned
into corners at considerable inconvenience. According to Bernie Knill, an obvious solution to such poor
planning techniques entails designing the baggage handling system with the building, and installing the
system as the surrounding structure is being built.
Chaos
The first time that BAE ran the baggage system for performance testing, the resulting chaos was sobering.
In March of 1994, the installation staff ran the BAE system for several media groups. Faults throughout
the entire baggage system destroyed bags and flung suitcases out of telecars. The next day, phrases like
"bags were literally chewed up," and "clothing and other personal belongings flying through the air" hit
newspapers. Telecars jumped tracks and crashed into each other. Suitcases went flying like popcorn
kernels, some of them breaking in half, spewing underwear in every direction. When the telecars crashed
into one another they bent rails and disgorged clothing from suitcases. Others jammed or mysteriously
failed to appear when summoned. Telecars crashed into each other especially frequently at intersections.
Many dumped their baggage off at the wrong place. Some telecars became jammed by the very clothing
they were carrying. As the telecars flung their bags off or ripped them open, the clothing clogged the
telecar rails, halting traffic and crashing other telecars in back. Most telecars holding bags with
unreadable bar codes were routed to holding stations. Other telecars that knew were they were going
collided with telecars that couldn't remember.
Unfortunately, in August of 1994, the system's performance was still poor. Even during planning of the
alternative tug and cart baggage system, telecars continued to collide and fall off their tracks. In late
August, Glen Rifkin of Forbes wrote, "Throughout the day, workers are seen unclogging tracks lined with
bags that have been cut in half." Morale was low among the installation crew. When asked how the test
bags were damaged, one worker replied in mock horror, "It's not eatin' bags. A truck ran over these
outside."
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Software
Ginger Evans, director of engineering for Denver International Airport, claimed that BAE didn't pay
enough attention to the programming issues early enough in the design process. She believed that alleged
troubles with building access or mechanical issues weren't the problem. "It's that the programming is not
done," she said. She faults BAE for this inadequacy. Others contend that many problems of mechanical
nature originated in the buggy software. According to Glenn Rifkin of Forbes, software sent out carts too
early or too late. Robert L. Scheier of PC Week alleged that it was the system's software problems that
resulted in the airport's 3,550 baggage telecars crashing into each other or becoming stranded along its 22
miles of track.
BAE president Gene DiFonso contested allegations of faulty software playing the central role in the
system's horrific performance by stating that "Software was not the major problem. It was an
electromechanical problem. The system was stutter-stepping because the electromechanical side wasn't
fully up to the software's capability." However, DiFonso admitted that program code had been a
nightmare at times. He revealed that the burden of writing code for establishing and maintaining
communication with the airlines' reservation systems was heavy. Particularly challenging was the duty of
connecting with United's Apollo reservation computers. A definite element in the disarray of the
communication software was the process of language translation, since BAE's computers had to converse
in the same software language as of each airline. Such translation work is painstaking and often laden
with bugs.
While writing code for the communication, tracking, and other numerous applications, the software grew
more complicated. As a consequence, the code completion agenda experienced the threat of becoming
unmanageable due to escalating levels of complexity. By principle, as program code grows in complexity,
it becomes increasingly hard to track or understand (see Complexity Of the System).
System Testing
Testing the system's mechanical side was unsuccessful. One source of frustration involved radio
communication between testers throughout the underground tunnels, concourses, and control rooms.
Engineers using radio communication in the concourses couldn't talk to their colleagues during testing
because of dead spots in radio transmission around the airport. Testing proved to be difficult and more
time consuming than BAE anticipated. BAE's employees worked around the clock, rarely surfacing for air
from the bowels of the system, as one BAE manager remarked. In September of 1994, BAE's parent
company, BTR Plc. of London, brought in the British-based PA Consulting to help debug the system. In
addition, BTR executives themselves began spending time in Denver working on the BAE design. The
influx of engineers, programmers, managers, and analysts improved the pace of testing. According to
Glenn Rifkin, that month, the 110 BAE employees got their first week off in two years.
Complexity
Admitting their ambition, Ralph Doughty stated, "We've done car-based systems before, but never this
large." The project's size and comprehensive nature caused it to experience a many problems due to
complexity. This is predictable when considering complexity theory (see "Complexity Of the System.")
Typically, systems with more than 10,000 function points are canceled 65 percent of the time, according
to Capers Jones. In Denver, the system's terrific workloads bogged down the network of distributed
computers that track luggage on the 3,550 telecars. Computers were tracking so many telecars that they
mistracked at times due to strict timing limitations. United believed that the tremendous workloads
warranted drastically reducing the system's complexity. To begin reducing the complexity, Denver
decided to completely cancel concourse A's automation design. The tracks and machinery serving
concourse C were redirected to concourse B as well. The number of destinations in the system went down
by a third when only one of the three concourses remained in the design. The number of destinations
decreased by an additional third when Denver decided to consider only outbound traffic on the remaining
baggage loop. Denver cut the system's track capacity rate from 60 to 30 cars per minute, when United
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argued that the computers needed to take more time to avoid mistakes. Along with the earlier changes,
cutting the rate of sorting on each track caused the overall system complexity to shrink by a full order of
magnitude. Unfortunately, the concept of a fully automated, high speed airport-wide baggage system
deteriorated to a less complete system with drastically reduced complexity, speed, capacity, performance,
and efficiency. This new system, however, worked well enough to open the airport.
Complexity Of the BAE Design
An example of the complexity in BAE's design is the act of summoning an empty cart from one place in
the baggage track circuitry to another. This seemingly simple action must take place up to a thousand
times a minute during standard airport operations. However, due to differences in empty telecar demand
throughout the airport, empty cars frequently must change direction, jump tracks, or switch to another
loop in the circuit. Because of the logistical difficulty of any of these maneuvers, special sequences can be
ordered by the computers. For example, to bring one empty telecar to its neighboring station, it may need
to merge with traffic going the opposite direction, exit at a special purpose intersection, avoiding other
telecar pileups or stalls. It may then dive down beneath the tracks at a special crossover point in the
intersection and merge with traffic running the correct way. It may then travel until it reaches its neighbor
station destination and exit at the intersection, only to find that it must change tracks to reach the
destination. There are countless variations of such traffic routines that the tracking computers must
generate in lightening-fast, error-free operation. To make matters worse, the patterns of system loads are
highly variable. The patterns depend on the season, time of day, type of aircraft, number of passengers,
percentage traveling with skis, and other factors. At peak times, all of the system's 3,550 telecars are in
motion. If a telecar interchange is popular enough, the telecars attempting to merge with busy traffic may
wait in cues of other telecars. The cue tracks are of limited length. Should a cue fill to the maximum, the
three hundred tracking computers must immediately detect the problem and transmit re-routing
instructions to all telecars in danger of crashing. It's like taking a city with 4,000 cars and no drivers in
them," says Ralph Doughty, vice president of engineering for BAE. "We have to be able to control all these
cars when they come to an intersection." Control can be hard to achieve when so many connection points
exist for the high speed telecars. Trying to predict the combinations of circumstances that the software
must control is difficult. Deciding how the computers must respond to each of the combinations is
difficult as well. When the wrong choices are made, the project can become a disaster.
SUMMARY
Lessons Learned
In ending any constructive narration of a project gone wrong, there likely are lessons to be learned. An
appropriate conclusion to this study revolves around the notion that in planning a project of such scale as
the BAE automated baggage system, great care must be placed in acquiring resources of information and
expertise to help make important judgments early on in the design process. Developers should pay close
attention to recommendations and advice of scholars as well as leaders of industry. Time-critical projects
like the Denver baggage system require not only solid reasoning, but good anticipation of problems. It is
of great importance that a timeline be built that allows for a generous testing phase. Technologically
advanced designs perhaps deserve more development and testing time than may seem proper. However,
the price of time will likely result in later payment in terms of improved accuracy and efficiency, just as
the BAE design promised. For purposes of meeting a steeper learning curve in operating advanced non-
traditional machinery, a good margin of error should be kept. Lastly, keeping the system's complexity
down to manageable levels will save time of prolonged testing, and money for redundant parts and skills.
Baggage System Growing Pains
While many of the smaller hardships experienced in the baggage system could have been more efficiently
resolved, in retrospect they seem to mark the system's technologically advanced growing pains. Larger
failures certainly could have benefited from better insight, although a variety of special circumstances
existed during their discovery. To discount the element of confusion or existence of many faults appearing
at once would be unfair, since the designers and builders of the BAE system lacked the luxury of time.
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More Than 10,000 Workers
Despite the poor reviews offered, the Denver baggage project has successfully emerged, and triumphed
over the many setbacks regarding its initial failure. For the wealth of knowledge that came from the
baggage system's affliction as well as more general airport trials, acknowledgment is due to the more than
10,000 people who devoted their time and energy to bringing the airport to a state of sound operation. In
light of the dismal times when the baggage system seemed to be in a state of unknown fate, the final
success deserves praise.
Prevention Of Crisis
In reflecting upon the automated baggage system's multitude of difficulties, United spokesman John Philp
summed up his feelings of the system's completion. "There are a lot of 'shouldas' and 'wouldas' and
revisionist history," he said. He is correct in hindsight. However, criticizing Denver, BAE, or United for
the baggage system's problems and inadequacies would only serve to lay blame to many of the hard
working employees who are responsible for bringing the system to its current state of operation. It is more
appropriate to place the troubled baggage system's problems in the context of solid management and
engineering principles. Hopefully, such analysis can reduce or prevent a system catastrophe from striking
as control and information systems grow larger and more liable every year.
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Airport 95: Automated Baggage System? [15]
History of the Automated Baggage System
When DIA's baggage handling system was planned in 1990, the consultants recommended carts pulled by
tugs for the long hauls and belt conveyors for the shorter distances. At that time, United Airlines was
opposed to the new airport and had not agreed to occupy the big Concourse B designed for them. In early
1991, United agreed to sign but stated a requirement for a baggage handling system that would enable
aircraft turnaround in 35 minutes despite the fact that the gates are more than a mile from the terminal.
Neither tug-and-cart nor belt conveyors could meet the time requirement.
United recommended BAE Automated Systems on the basis of a demonstration of a prototype system.
Since the Denver city charter mandates a bidding process, system requirements were defined and the
specifications sent out for bids.
BAE Design Approach
The design is an automated system based on single-bag destination coded vehicles (DCV's). BAE's name
for its system is Telecar. The vehicles are referred to as cars or carts. In proposal language they are called
destination coded vehicles (DCVs).
• Bags are conveyed from check-in
• Scanners read the bar code labels as the bags are being conveyed.
• Data from the bar code scanner are processed to a radio frequency identification transponder mounted
on a car that is barreling into the loading area.
• The car is loaded on the fly and is directed to its destination gate by the radio frequency identification
transponder. DIA's baggage handling system is centered on track-mounted cars propelled by linear
induction motors. The cars slow down, but do not stop, as a conveyor ejects bags onto their carrying
platform. During baggage transfer, a scanner reads the bar coded label on the bags and transmits the data
through a programmable logic controller to a radio frequency identification tag on a passing car. Now the
car knows the destination of the bag it is carrying, as does the computer software that routes the car to its
destination.
Design Issues
Cars propelled by linear induction motors.
In the Denver system a fin on the bottom of the car passes through a slot in the motor mounted under the
track. The electromagnetic field of each motor drives the car forward to the next motor. Fast, straight-
ahead travel is no problem. Problems develop when stops, slowdowns and diverts are built into a high-
speed system that has plenty of curves, inclines and declines. The use of vertical friction wheels and
permanent magnets to fine tune a linear induction motor system is more an art than a science in a system
the size of DIA.
Bar code scanning and radio frequency identification.
Handing off information from bar code scanners to a radio frequency identification system has been a
proven technique in industrial material handling systems. It has never been tried in a high-speed baggage
handling system that employs conveyor-to-car transfers on the fly.
Empty cart management software.
The DIA car-on-track system, is a high-risk automation approach in which the whole system must
respond in real time to an incredible number of questions and commands generated by the empty cart
management software.
Recommendations by Consultants.
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The airport baggage handling system evaluation committee was aided in its decisions by consultants from
Breier Neidle Patrone Associates. In 1990, a BNP study stated that the advantages of a multi-bag DCV
system include:
• Minimum processing times, providing essentially equal service to all concourses
• High throughput capacity
• High reliability
• Oversize baggage-skis, golf clubs-capability
• Minimal development risk
• Availability from two proven suppliers: BAE and UTDC.
In 1990, Breier Neidle Patrone Associates further stated: "With regards to the single-bag DCV,
considering the prototype state, we strongly feel it is not capable of being implemented within the project
schedule."
System Hardware Components
The automated baggage handling system comprises two main components:
1. high-speed, bag-carrying telecarts mounted on tracks
2. connecting conveyor belts to load and off-load baggage.
The tracks are suspended from the basement ceilings of the terminal and concourses. Electric motors and
synchronous drives move the telecarts along the tracks at varying speeds. Photocells and radio frequency
reading devices direct each telecart to the right location. In total the original system included:
• over 17 miles of track
• 5.5 miles of conveyors
• 4,000 telecarts
• 5,000 electric motors
• 2,700 photocells
• 59 laser bar code reader arrays
• 311 radio frequency readers
• over 150 computers, workstations, and communications servers
The computers comprise 30 Texas Microsystems Inc. 386 and 486 PCs running customized control
software. BAE used Microsoft Windows on workstations and IBM OS/2 on servers. A fault-tolerant
database server from Vista Corp. tracks baggage movement and confirms the delivery of carts at particular
sites.
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ODL 121 Systems Design Coursework [16]
Introduction
Denver International Airport (DIA) was an ambitious project approved in 1989, and the anticipated
completion date for the entire baggage system was October 31, 1993. The initial idea was to build an
advanced and unrivalled airport capable of landing 3 aircraft simultaneously, in adverse weather, using 5
initial runways (with 12 runways planned in total), and was to run services for 20 airlines. The control
tower for instance has an unobstructed view of over 3 miles and is 327 feet tall (the tallest FAA structure
in North America).
Due to the delays and problems surrounding the project, only one airline was using the airport when it
was finally opened on February 28th 1995 (the final opening date was set by Denver Mayor Wellington
Webb after a series of (the initial date for opening was in October 1993, then March 1994). The airport did
achieve one of its goals shortly after opening. The event was a triple simultaneous landing in adverse
weather, landing-a United 727, 757, and a Continental 727 at 7:35 a.m
The baggage handling system was estimated at 193 million, using a computer tracking system to direct
baggage contained in unmanned carts that run on a track. The system cost another $88 million dollars
and the associated delay reportedly cost Denver city $1.1 million per day in operations costs and interest
on bond issues. The total cost for the airport was 4.2 Billion dollars. The total cost of baggage handling at
DIA came to an astonishing $311 million, (including the Rapistan backup system).
Statistics
Denver airport consists of :
7 control rooms Each with redundant arrays of 7 PLCs Locally,
Ethernet interconnects all 14 PLCs
Each control room also has 4 PCs
Backbone network is also 10Base-2 Ethernet Interconnects
7 control room PLC arrays
Connects to Master Control Centre PCs
8 PCs controlling Operator Station
Denver covers over 53 square miles
5 runways (12 planned)
3 landings simultaneously in all weather conditions
Built to house and facilitate 20 major airlines
Baggage cost $193 million (plus $88 million).
4000 telecars for 21 miles of track
Laser scanners read barcodes on luggage tags
Photocells track telecar movement
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Controlled by 300 computers
* (Information used from: - controlnet.org. full web address in reference section)
How it Works
The system consists of the following components: - Conveyor Barcode Reader, to read the information on
the luggage tags Array Baggage cart, to transfer the luggage to its respective gate/terminal and aircraft
RF/ID Tag, attached to the luggage with the passenger/customers details and destination etc RF/ID
Reader These components are integrated, and may be shown in the following diagram (fig 3.1)
FIG 3.1
The actual network consists of: -
Baggage
Check-in
Departure Gate
Departure Gate
Manual Sortation
10Base-2 Ethernet
Diversion points
And is graphically demonstrated in the following diagram (FIG 3.2)
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Fig 3.2
Each bag or suitcase is put into a bar coded car (Destination Coded Vehicle (DCV)), after being checked in
kerbside counters with information on its destination. A computer dispatches and routes the DCV from
the terminal to concourse make-up units near airline gates. The system is also set up to handle skis or
other oversize items, which can be checked at kerbside The destination could be to a terminal, ready for
loading onto the plane, or delivered to other terminals for connecting flights anywhere in the airport. Each
of the 400 cars (DCV's) is tracked via a series of laser scanners, and the location is sent to a computer. The
computer then searches it's database with information regarding flights routing and the gates that the
luggage needs to be distributed to, and the computer then controls the track equipment such as points
(track switches), and motors. The system is also set up to handle oversize items, which can be checked at
the kerbside. * (Information used from: - Ethernet, A Host for Control Level Networks. By Richard H.
Caro Vice President, Network Technologies Automation Research Corporation)
Comparisons and factors, which contributed to the system's failure
Hardware
The Denver baggage system was designed by BAE automated systems and based on a similar
implemented baggage control system already implemented at Frankfurt airport in Germany, also
designed and provided by BAE, although not to the same scale as DIA.
The hardware itself consists of 4000 Telecars on 21 miles of track. 300 computers using photocells
control the cars, which is one of the factors relating to the failure and delay of the baggage system.
The photocells and laser scanners pass the car locations, velocity and other required data to the
computers, and the computer would then use databases of routing information, flights and gate numbers
to direct the luggage to its respective destination.
The commitment and frequency of operation for the baggage cars are highly variable. The volume of
luggage depends on the time of day, season, and number of passengers and percentage of luggage with
oversize loads. 3,550 telecars could be in operation simultaneously.
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If a track interchange is popular enough, the DCV's attempting to merge with busy traffic may wait in cues
of other DCV's.
The cue's can only accommodate a certain amount of DCV's, so if a queue is at it's maximum capacity, the
three hundred tracking computers must immediately detect the problem and transmit re-routing
instructions to all DCV's that may collide.
During the testing phase, the luggage was misrouted, the luggage fell out of the cars (some of the car
latches were faulty), and on a number of occasions, the cars collided and derailed.
The optical sensors also fouled regularly, and had been knocked out of alignment on several occasions,
which also contributed to car collisions etc.
Optical sensors under certain conditions (particularly in dusty enclosed tunnels for instance) may not
have been the best solution, and some consideration should have been given to other sensors such as Hall
effect reed switches, that are durable and are more durable in external conditions.
Electrical surges tripped breakers on some of the system's 10,000 motors.
Sometimes, the airport's erratic power generation shut down the system totally. During detailed electrical
tests, electrical power feed systems fluctuated; causing the surges that disrupted the system's operation.
An initial survey of all the associated equipment (regarding the electrical equipment), may have
highlighted a significant shortfall in power supply capabilities, for instance, when a single phase AC motor
initially starts to rotate, the current drawn can be from four to eight times greater than the nominal
current drawn, once the rotor has started moving.
This is normally 'factored in', and would have been accounted for when assessing a single system.
The airports electrical system designers may not have accounted for all the systems to be commissioned at
the same time (as per the full scale test highlighted on London university's Top class computer science
website), and the current drawn could have exceeded the normal estimated running current up to eight
times. BAE installed 'special industrial power filters to smooth the flow of power' to alleviate this problem,
and could work to a certain degree.
Basically, a filter would consist of capacitors and resistors. Capacitors take a certain amount of time to
'charge up', then discharge, as the power changes from its positive state to negative (AC power).
Because of the time lag characteristic with capacitors, a sudden current draw would discharge the
capacitor before it could impact on the supply charging it (depending on the size etc of the
capacitor/ filter cct).
This approach (along with High Rupturing Capacity fuses fitted to most industrial ccts
incorporating Ac motors and generators (due to their initial current flow capacity, before
blowing)). The incorporation of these filters, I believe would be a 'quick fix' method, for a
fundamental flaw in the electrical design of the system.
Other issues with the hardware include: -
Poor aerodynamics needed to be redesigned due to instability caused by eddies within tunnels.
Bumpers badly sited, interfered with other carts.
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Badly printed/dirty labels. In tests of the system, bags were mis-loaded, were misrouted, or fell out of
telecarts, causing the system to jam.
On some occasions during the testing phase, the photo eye at one of the locations could not detect the pile
of bags on the belt and hence could not signal the system to stop.
'The baggage system also loaded bags into telecarts that were already full. This caused bags to fall onto the
tracks, causing the DVC's to jam. This problem occurred because the system had lost track of which
telecarts were loaded or unloaded during a previous jam. When the system came back on-line, it failed to
show that the telecarts were loaded. The timing between the conveyor belts and the moving telecarts was
not properly synchronized, causing bags to fall between the conveyor belt and the telecarts. The bags
became wedged under the telecarts, which were bumping into each other near the load point.' This
excerpt was taken from the following resource:
Software
More than twenty programmers worked undisrupted for two years to write the software, which may
highlight the complexity of the software needed for this system. Computers were tracking so many
telecars that they miss tracked at times due to strict timing limitations.
A project this size was difficult to simulate, so when the system started to malfunction due to its
complexity, tedious trial-and-error debugging methods were used to try and rectify the problems
incurred.
The company (BAE aero systems) had limited experience with a project of this size and complexity, even
considering the fact that BAE automated systems had developed and commissioned the Frankfurt system.
Since the system's conception, the designers made increasingly large changes to it.
When the system failed, Denver handed control over the project to United Airlines, who became the
systems integrator. United declared that they would make the Denver system 'work' by reducing its
complexity and performance.
By June 1993 cars were running in Concourse B but all the Programming, which was solely in the hands of
BAE, was not done. There were software errors, which coursed the routing of the cars to waiting pens
when actually they were needed. There were so many bugs in the system that about 50% of the total
budget was required to fix it.
There were scanners, which were becoming dirty (see Hardware section of this report), so the codes was
unable to be read through the scanner and the cart has gone through without being acknowledged.
Design methodology
Since the system's conception, the designers made increasingly large changes to it.
In August 1992 United Airlines changed plans for a transfer system for bags changing planes requesting
that BAE eliminate an entire loop of the track from Concourse B, as they wanted to operate with one loop
instead of two.
Although the change saved about $20 million, it required the system to be re-designed.
There were changes to the system late in the design and the pressure of the deadline was as strong.
No backup system incorporated in the original design.
No attempt at staggering the introduction of system, hence all eggs in one basket.
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Not an integral part of the airport design but an afterthought, adding design constraints in that the system
had to occupy existing tunnels (possibly causing problems regarding aerodynamics covered in the
hardware section of this report). No individual taking overall responsibility for the project.
Estimates of time and costs involved totally inadequate.
Huge increase in complexity over existing systems renders their use as role models invalid (possibly due
to BAE's inexperience with projects of this size).
Operation and maintenance
Ethernet collisions are the main problem.
There were also too many messages on the backbone LAN.
Too many low level messages routed via the backbone LAN.
Power surges and fluctuations caused problems with the circuitry and motors.
The filters to cure this problem took 6 months to arrive causing delays.
There was no time given to test the system, in Frankfort the system was running for 2 years testing before
going live
* (Information used from: - Barbara Cook, a columnist for 'Airport magazine'. full web address in
reference section).
Assessment of system failure contributions - Human errors in operation.
Project started with no commitment by major airlines to the project.
In February 1993 the Mayor of Denver delayed the project from its scheduled date of October 1993 to
December 19, 1993 and then to March 9, 1994.
In September 1993 the project was delayed again to May 15, 1994.
Lack of consultation and training of users.
In August 1992 extra ski-claim devices and odd-size baggage elevators had to be installed in 4 out of the 6
sections of the terminal adding $1.6 million to the cost of the system.
In September 1992 Continental airlines requested that automated baggage sorting systems be added to its
West basement at a cost of $4.67 million.
In January 1993 maintenance tracks were added to permit the Telecars to be serviced without having to
lift them off the main tracks.
This cost an extra $912,000. In January 1994 United Airlines requested changes to its odd-size baggage
inputs at a cost of $432,000.
Inadequate communications between client and providers.
The City did not find out from the airlines what was required in the system design i.e. what the system
was required to do or what type of features was required. There were too many changes made to the
system, but the expected time was not extended. The designer looked at the problems as they came in only
as patch of the problems rather than the system as a whole. In addition, the Denver Airport authorities
continually made changes without letting the system designers know of these changes. The time that was
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allowed for testing and developing the system was not enough. The only other large baggage system is at
Frankfurt Airport in Germany. It took six years to develop the system and another two years to test and
debug the system whereas the in Denver BAE were asked to do it in two years. It is believed that because
of the electrical problems there were only six weeks for testing the system.
Evaluation of system failure attributes - The social, political and economic context of the
system's development.
City put a lot of pressure on BAE to complete the baggage system even after changes were made late into
the development without factoring in any additional time for the extra work and additional testing this
caused.
Michael Fumento's report suggests that the whole project was politically motivated.
He disputes Frederico Pena's reasons for replacing Stapleton Airport with Denver, by suggesting that
passenger numbers were falling and that the flight delay record was actually better than average.
He also points out that Stapleton had been recently expanding until blocked by Pena, and that the new
location is less conveniently located.
The fact that the project went ahead despite being advised in a consultancy report that it was untenable
within the projected timescales (Sommerville) would lend credence to this.
Indeed the sheer scale of the project points to the pursuit of glory rather than any practical benefits.
Claims that the additional costs caused by delayed opening were not passed on to the residents of Denver
must also be offset by the increased charges faced by the airlines, and ultimately the passengers, many of
whom, presumably will reside within the catchments area of the airport.
Denver-originating passengers will pay higher ticket prices - because it cost Denver about
$33.3 million each month that the airport remained closed.
It was the mayor of Denver who announced the final deadline and opening date for the D.I.A, after the
continuing embarrassment the airport had caused the city of Denver, at national level.
With each new problem and delay, the ratings for Denver's airport stocks dropped. This made it difficult
for Denver to issue new bonds.
The cost of delay (largely due to the baggage handling cost Denver an estimated $1.1 million.
Part of the debt was absorbed by the city and county of Denver.
The airlines bailed out the rest of the debt which may have been a contributing factor in Continental
Airlines filing for bankruptcy.
In the later stages of the project, the bonds became almost worthless, and the city of Denver would find it
very difficult to raise further revenue for the airport.
The total price tag for sixteen months of delay came to around $500 million dollars. Half of this enormous
amount went to debt service, such as paying interest to bondholders.
The other half was paid for operations and maintenance of Stapleton and Denver International Airport
combined
The first test of the baggage system (done without notifying BAE first).
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City put a lot of pressure on BAE to complete the baggage system even after changes were made late into
the development.
Not much time was given for testing.
Lack of, or miss-application of a regulatory framework of standards
Operational concerns over safety, reliability and working conditions.
Again an automated system so safety of operatives and customers not at risk, but there was an increased
risk of damage to luggage and the components of the system itself e.g. carts.
Situation financially damaging also in terms of discouraging custom and paying out compensation to
affected passengers.
Employees at greater risk of stress from dealing with irate customers, and the associated negative impact
on morale. Ultimately job security would be jeopardized.
· An efficient baggage handling system was absolutely intrinsic to success of airport given its size, however
none of the agents involved in its implementation seem to have placed enough importance on this fact. the
social, political and economic context of the system's development. The first test of the baggage system
(done without notifying BAE first). City put a lot of pressure on BAE to complete the baggage system even
after changes were made late into the development.
Not much time was given for testing. Problems can be defined in areas where some of the scanners got
dirty and were knocked out of alignment therefore could not detect the cars going by consequently casing
some crashes.
This may have been avoided with more vigilance and staff recruitment. Power surges through the airports
electrical system caused problems with the baggage system where many circuits were blown.
Luggage got dumped on the tracks between stops. This all contributed to errors particularly with some
attribution to the software errors.
Operational concerns over safety, reliability and working conditions.
There was no back up if the system was to fail.
There was no room for the tugs and cart to cope with the amount of baggage expected nor was access
roads available between check in facilities and the aircraft.
The safety of the baggage was much of a concern as baggage carts were jamming on the tracks when the
baggage was being thrown off the carts.
This intern delayed the carts from moving on.
Summary
The baggage system was initially to serve concourses A, B, and C, service is for concourse B only.
Even though concourse C previously had its part of the automated system working, its components were
scrapped and added to concourse B, (which had failed testing). Concourse A and C are supplied by the old
tug and cart system.
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This traditional system cost $71 million, and was designed and installed by Rapistan Damage
Corporation.
The traditional system implemented on concourse A and C is still quicker than at Stapleton airport, but is
still slower than the theoretical speed of the automated baggage system and is labor intensive.
Further changes to make the system work include the tracks serving both concourses B and C to be
repositioned to serve only concourse B, which further affected the systems efficiency.
Additionally, each track's 60 vehicle per second capacity was limited to 30 vehicles per second, further
affecting efficiency. Only half of the 84 airport's gates were served, and at only 12 percent of the system's
capacity. Instead of handling originating, terminating, and transfer baggage, the automated system
handled only baggage originating in Denver.
Computer simulations to better assess feasibility.
Phased introduction. Backup system to be available during introduction and subsequent operation.
Reduced scale and more realistic timescale and budget.
An overall manager with extensive knowledge of the system's requirements, prepared to liaison with all
users, and arbitrates over requests for changes after planning stage completed.
Completely restructure control system Big 6 Consultant approach.
No understanding of PLC use .
No understanding of correct network architecture .
Rebuild network Install 100Base-T at all levels
Peak network load reduced to 5%.
System problems would remain, but not masked by Ethernet collisions
Stapleton Airport has now closed and its "DEN" identifier transferred to the new facility.
On opening day itself, Hinson declared that within two hours of its ribbon-cutting, DIA, the first major
airport built in the U.S. in 21 years, had already begun to pay dividends in improved airspace system
capacity.
Delta and American recently withdrew from negotiations with the city to operate from some of the unused
Continental gates, saying they would rather continue using Concourse C, which has the old-style tug and
cart baggage-handling system.
Between August 1994 and February 1995, the city had the backup system installed and it is available to all
airlines that serve DIA.
According the project manager at the time (Gene Cochrane), O'Brien-Kreitzberg functioned as
construction manager on the alternate system and, delivered the completed conventional baggage system
four weeks ahead of schedule at a cost of $49.5 million, $3.4 million under budget.
To recoup some of its losses, Denver initiated a formal dispute with BAE regarding the alternative manual
baggage system. Denver argues that the alternate system's $71 million dollar price should be paid by BAE,
since its problems made the backup system necessary.
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Denver may have considered litigation with BAE for other delay incurred losses, but would likely have
waited until BAE's work had finished to avoid spawning further delays due to legal struggle.
At the time of this writing, no lawsuits have been filed between the two groups.
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Is It Really Ready To Fly? [17]
Denver's new international airport opened Feb. 28 and city officials held their collective breath as the
airports infamous, high-speed computerized baggage system--plagued by computer software glitches and
mechanical failures from the outset--kicked into operation.
While officials at the company that built the system say it works, others insist that problems are nowhere
near solved. "This is a system that has proven not to work," says Michael Boyd, president of engineering
consultancy Aviation Systems Research Corp. in Golden, Colo., who has followed the Denver International
Airport (DIA) saga from the start.
Technical complexity, unrealistic deadlines, and indecision forced airport officials to greatly scale back the
project. The system is moving only 30 to 60 bags per minute, well below the estimated 1,100 per minute
for the fully operational system.
'21st Century' Design
DIA, the first major new U.S. airport in 20 years, finally opened after a 16-month delay and at a cost of
nearly $5 billion, almost $3 billion more than originally projected. The airport's baggage system,
considered a key component of its "21st Century" design, was to have revolutionized check-in and retrieval
and save airlines money and passengers time.
On opening day, the automated system worked with just some minor mechanical problems. "This is the
largest real-time package control system ever built, and it's working smoothly," says Gene DiFonso,
president of Dallas-based BAE Automated Systems Inc., which built and maintains the system.
However, DIA is running only a small-scale version at just one concourse, and aviation experts say that's
hiding technical problems that could cost airlines millions of dollars in lost, damaged, or misrouted
luggage.
Diane Coller, Denver's deputy director of aviation, concedes the system's troubles may not be over. "We
relied on technology that was ahead of its time," she says. Even on a small scale, the system is running at
only a 90% success rate, says Paul Earle, a Denver-based engineer. "That means 10% of the bags didn't go
to the right place," he says. "Airlines can't live with a 10% failure rate."
A Mini-Railroad
The baggage system includes a massive underground network of 20 miles of tracks that carry 3,200
baggage carts to various airport locations. A combination of laser bar-code scanners, radio-frequency
transponders, and 30 Texas Microsystems Inc. 386 and 486 PCs running customized software controls
the movement of carted bags--up to 1,100 a minute when the system is fully operational--between gates,
baggage carousels, and curbside drop-off points.
BAE is using Microsoft's Windows on workstations and IBM's OS/2 on servers. A fault-tolerant database
server from Vista Corp. tracks baggage movement and confirms the delivery of carts at particular sites.
The baggage system is designed to run up to three times faster than conventional "tug-and-cart" systems
used at many other airports. This is crucial at DIA, where buildings are spread out across 34,000 acres.
The concourse using the automated system is operated by United Airlines, by far Denver's largest carrier.
United, in fact, took over the project from the city of Denver last September and worked directly with BAE
to hasten the opening of the airport, says an airline spokesman.
BAE's Di Fonso says his company wasn't given adequate time to develop the software that controls cart
movement. "This is an enormous system. Along the w ay it became apparent that this would be a lot more
difficult to do than we thought," he says.
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Richard de Neufville, chairman of the technology and policy program at the Massachusetts Institute of
Technology and an instructor in airport systems planning, agrees. "This project was doomed because
[BAE] only had two years to do it. That's too fast for this kind of thing," he says.
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Webliography
[1] Bozman, Jean S. (1994, October 10). United to simplify Denver's troubled baggage project
[ComputerWorld] [WWW Document]. URL http://www.computerworld.com/news/1994/story/
0,11280,8903,00.html
This resource contains a news article about breaking developments (circa 1994) in the BAE
luggage handling system at Denver International Airport. CS 680 students will find this
resource helpful because it is a factual story. It deals with the BAE problem from the
perspective of industry professionals searching for a solution. This should not be surprising
considering that the article was published by ComputerWorld Magazine. This resource can be
trusted because ComputerWorld is an industry publication, widely read and trusted by IT
professionals.
[2] Chandler, David (1994, January 26). It’s too late to bag DIA’s automated luggage system – no
matter how many suitcases it eats [WWW document] URL http://www.westword.com/issues/1994-01-
26/citylimits2.html
This article, which appeared in Denver Westword, contains a news report about the baggage
system used at DIA and the issues occurred when it failed. It further gives the reasons for
failure and its aftermath. It tells the inside story and presents views of DIA and BAE officials,
and also the views of the consultants. It also describes the baggage system used at DIA.
[3] Dempsey, Paul Stephen (1999, January 8). Airport woes a wake-up call [Denver Business Journal]
[WWW Document]. URL http://denver.bizjournals.com/denver/stories/1999/01/11/
editorial3.html
This resource contains information about airports throughout the world which have had
failures similar to DIA. CS 680 students will find this resource helpful because it gives an
overall picture of software failure in international airports and helps students realize that DIA
is not a unique situation. This resource can be trusted because the author is a professor of law
at the University of Denver and the resource was printed in the Denver Business Journal.
[4] Donaldson, A.J.M. (2002, May 27). A case narrative of the project problems with the Denver
Airport baggage handling system [PDF document] URL http://www.cs.mdx.ac.uk/research/SFC/
Reports/TR2002-01.pdf
This case narrative, prepared for Software Forensics Center and classified as TR 2002-01,
contains the chronology of events that led to the late opening of DIA. It elaborates on the
project management issues and gives a comprehensive narrative of Harvard case study on
DIA Airport Case. It focuses on the project management aspect so vital to developing
professionalism in workplace.
[5] Garrett, Mary (2002,February 2). Case study demo [WWW document]. Lansing Community College.
URL http://vcollege.lcc.edu/cisb200/casestudy_demo.htm
This resource takes the DIA case as a case study and gives a thorough explanation on it. It
tries to find the reasons behind the failure of the automated luggage system at DIA and
proposes some solutions. The interesting part is that it correlates the technical, management
and organization solutions to solve the problem and gives an idea about how can these factors
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Denver International Airport (DIA) Case
affect an Information technology project. CS 680 students will find this resource useful as it
specifically discusses the DIA automated luggage system project from a technical as well as
professional standpoint. I believe students will benefit from reading about the correlations
between the various fields present in a project. We can trust the resource as it was published
on a university website and the author has listed a number of references at the end.
[6] General Accounting Office (1994, October 10). New Denver Airport: Impact of the delayed baggage
system [WWW document] URL http://ntl.bts.gov/DOCS/rc9535br.html
This resource, which is classified as GAO/RCED-95-35BR, contains detailed information
about problems with the baggage handling system, the added costs due to the delay of the
opening of the DIA and other financial aspects like the expected revenues, thus giving both
the technical and financial aspects. It also gives details about alternative, conventional
baggage handling system that can be used until the automated system is operating.
[7] Gibbs, W. Wayt (1994, September). Software's chronic crisis [Scientific American] [WWW
Document]. Georgia State University. URL http://www.cis.gsu.edu/~mmoore/CIS3300/handouts/
SciAmSept1994.html
This resource appears to be the definitive text on the DIA/BAE fiasco. The author, Gibbs, is
mentioned or cited in many of the other DIA articles uncovered during this research. This
article is informative, easy-to-read and broad in scope. CS 680 students will find this
resource helpful because the article also provides a solid background about the complexity of
software engineering. While the lead-in story deals with the BAE software application
designed to run the automated luggage system at Denver International Airport (DIA),
additional real-life case studies are sprinkled throughout the story. Stories such as American
Airlines SABRE system, California's Dept of Motor Vehicles system and the US Dept of
Defense Clementine satellite system add depth to the topic at hand. This resource can be
trusted for two reasons. First, the site hosting the article is the Computer Information
Systems Dept at Georgia State University and second, the article is copyrighted by Scientific
American magazine.
[8] Grimson, Jane B. & Kugler, Hans-Jurgen (2000). Software needs engineering: a position paper
[The ACM digital library] [WWW document]. URL http://delivery.acm.org/10.1145/340000/
337446/p541-grimson.pdf?key1=337446&key2=6825329801&coll=GUIDE&dl=ACM&CFID=
24029910&CFTOKEN=45701350
The paper tells that developing software isn’t the end of road. It may require more care in the
future. It explicates a number of reasons for which a software system can fail. It takes the
DIA automated baggage handling system as a case study and explains it. It tells that we need
both programmers and software engineers for successful software development and
operations. This resource is very helpful for CS 680 students as it discusses on useful policies
for developing successful software. It also mentions some reasons for which a software system
can fail. The resource can be trusted as it was a paper published by two researchers, one from
a reputed university and another from a well known research lab. The contact numbers and
email ids of the two authors have been mentioned. They can be reached at
Jane.Grimson@cs.tcd.ie and HansJurgen.Kugler@q-labs.com.
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[9] Montealegre, Ramiro & Keil, Mark (1999, May 12). De-Escalating Information Technology projects:
Lessons from the Denver International Airport [MIS Quarterly, under review] [PDF Document].
Universidad Torcuato Di Tella. URL http://www.utdt.edu/congresos/empresarial/papers/
montealegre.pdf
This resource contains a very scholarly review of the failure of the BAE luggage handling
system at Denver International Airport. CS 680 students will find this resource helpful
because it is a work of a scholarly nature and provides a detailed account of the DIA fiasco.
Interestingly enough, a comparison of the text in this article with the text of another posted
article, "Software's Chronic Crisis", Gibbs, shows some overlap in verbiage. This is interesting
because the Gibbs article is hosted by Georgia State University which is where Mark Kiel, co-
author of this article, is listed as working. This article appears to be reputable. It is hosted by
the Universidad Torcuato Di Tella in Buenos Aires, Argentina. The credentials of both authors
are listed in the article. Ramiro Montealegre hails from the University of Colorado at Boulder
and Mark Keil from Georgia State University. The article includes reference to numerous
academic degrees held by each author. This article appears to have been written by scholars.
[10] Nash, Kim S. (2000, October 30). Companies don't learn from previous IT snafu's
[ComputerWorld] [WWW Document]. URL http://www.computerworld.com/networkingtopics/
networking/management/story/0,10801,53014,00.html
This resource contains an interesting look at various IT project failures over the past years.
One of the cases mentioned in a side bar snippet is the BAE failure at Denver International
Airport (DIA). CS 680 students will find this resource helpful because it provides a nice
overview of various IT mistakes or, as the author calls them, snafu’s. Rather than focus on one
event, the article discusses the need to learn from past mistakes and then proceeds to review
several real-life examples of good ideas gone bad. A well written and interesting article. This
resource can be trusted because ComputerWorld is an industry publication, widely read and
trusted by IT professionals.
[11] Neufville, Dr. Richard de (1994, December). The baggage system at Denver: Prospects and lessons
[Journal of Air Transport Management, pp 229 – 236] [PDF Document]. Massachusetts Institute of
Technology. URL http://ardent.mit.edu/airports/ASP_papers/
Bag%20System%20at%20Denver.PDF
This resource contains a good review of the BAE luggage system failure at Denver
International Airport (DIA). It also has a description of the automated baggage system, how
it was designed, expected to be operated and the reasons behind its failure. CS 680 students
will find this resource helpful because it provides a detailed explanation of the automated
system, the system expectations and why the system failed as a result of a few incorrect
decisions. The article is well written, appears to be factual and is not too long. This resource
can be trusted because it appears to be posted at the Massachusetts Institute of Technology
web site. The author is listed as a PhD and there is reference to this article being included in
Journal of Air Transport Management.
[12] Poulson, Barry (1994, May 25). A quota by Any other name: The cost of affirmative action
programs in the construction of Denver International Airport [Independence Institute, Issue Paper 6-
94] [WWW Document]. URL http://i2i.org/article.aspx?ID=630
This resource contains a conceptual framework for measuring the costs of affirmative action
in terms of the estimates of affirmative action costs in the construction of DIA, and policy
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implications. CS 680 students will find this resource helpful because it raises social and
administrative issues related to affirmative action programs. This resource can be trusted
because the author is a Senior Fellow in Economic Policy at the Independence Institute and a
Professor of Economics at the University of Colorado.
[13] Proctor, Stacey (2000, February 28). DIA marks anniversary [The Daily Camera] [WWW
Document]. URL http://www.broomfieldenterprise.com/news/local/28ldia.html
This resource contains a newspaper article on the progress Denver International Airport
(DIA) has made in the years since it opened in 1995. CS 680 students will find this resource
helpful because it provides a ―what happened‖ ending to all of the case studies surrounding
the fiasco of the DIA/BAE system failure. It mentions that the luggage handling system was
finished in October 1995 and now performs as expected. This resource can be trusted because
it appears to be hosted by the company that owns the newspaper.
[14] Schloh, Michael (1996, February 16). Analysis of the Denver International Airport baggage system
[WWW Document]. California Polytechnic State University. URL http://www.csc.calpoly.edu/
~dstearns/SchlohProject/csc463.html
This resource discusses events at the new Denver International Airport that resulted in
opening delays at the airport. The scope is limited to the automated baggage handling system,
which was the primary source of failure warranting the airport's several opening delays.
Analysis of the failing system is comprehensive. Research is conducted using a variety of
sources. CS 680 students will find this resource helpful because it offers an objective and
thorough examination of the factors behind the DIA baggage-handling fiasco. This resource
can be trusted because it was reviewed by members of the School of Engineering at Cal Poly.
[15] Swartz, A. John (1996, March). Airport 95: Automated baggage system? [ACM SIGSOFT Software
Engineering Notes, 21(2), 79 – 83] [WWW Document]. URL http://portal.acm.org/
citation.cfm?id=227544&coll=Portal&dl=GUIDE&CFID=24021259&CFTOKEN=76554811
This resource, which appeared in ACM SIGSOFT Software Engineering Notes Volume 21
Issue 2, contains the history, software design and the project management paradigm related
to the baggage handling system operated at DIA. It gives a concise and precise account of the
software design approach, the system layout and the problems, both mechanical and
software, related to the BAE baggage handling system at DIA.
[16] Trevour, Richard. Brookes, Philip, Bertola, Tony & Toal, Sandra (n.d.). ODL 121 systems design
coursework [WWW Document]. URL http://www.brookes007.btinternet.co.uk/
Courseworkweb_files/denvercoursework.htm#top
This resource appears to be a team assignment for a group of college students attending the
Queen Mary, University of London. The assignment is an analysis of the Denver
International Airport luggage handling fiasco. This resource provides an outline of the overall
problem along with a text write-up of the problem. Tables and diagrams are included.
Research references are provided.
[17] Violino, Bob & Kapustka, Paul (n.d.). Is it really ready to fly? [InformationWeek] [WWW
document]. URL http://www.informationweek.com/518/18iubag.htm
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At the time this article was written, it was a real-time write-up of the BAE luggage handling
failure at the newly opened Denver International Airport (DIA). CS 680 students will find this
resource helpful because it presents elements of this story from an insider’s point of view. The
authors approach the story from a working IT perspective, not an academic perspective. This
resource can be trusted because it is posted on the Information Week Magazine web site.
Information Week is a trade periodical widely read and trusted by many IT professionals.
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