EXPERIMENTAL METHOD by pengxiuhui

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									                Flight Mode Annunciation Survey Questionnaire
1. SURVEY OBJECTIVES
Flight mode annunicators are used on modern aircraft to tell the pilot or flight crew what the
autopilot and/or automation devices are doing. Experience since the introduction of complex
automation on modern transport aircraft has shown that the flight crew has not always possessed
good situational awareness of the present and future behaviour of the automation, and this has
resulted in serious incidents and fatal accidents.

An FMA has been developed which portrays information in a graphical rather than alphanumeric
format. The objective of this questionnaire to determine if the graphical FMA concept offers any
cognitive advantage over the present alphanumeric display. This survey forms part of a master‟s
thesis being undertaken in collaboration with the International Test Pilots School in Coventry, UK,
and the Faculty of Engineering at Bristol University, Bristol, UK.

2. SURVEY METHOD
This survey will outline the present alphanumeric FMA as used on the Airbus A320, using several
examples. The proposed graphical FMA will then be explained. You will be shown a series of FMA
„scenes‟ (for both alphanumeric and graphical FMA) that make up an aviation „scenario‟ such as a
takeoff or autoland sequence. You are then asked to rate both displays on a cognition scale, answer
questions comparing the displays, and finally your opinion is sought on the general concept of the
graphical FMA. (When viewing this survey on a CDU, use the page layout view with the page
width occupying full screen width for best resolution.)

3. CONFIDENTIALITY
As this survey does not require you to identify yourself, all information supplied is completely
confidential. If you wish to identify yourself so that I can contact you for further information if
required, you are invited to do so at the end of the survey.

4. A320 ALPHANUMERIC FMA DESCRIPTION
The flight mode annunciators are located
on primary flight display (PFD) for the
captain and first officer, and occupy the
top ~20% of the display. The diagram to
the right shows the general arrangement
of an A320 FMA pictured during an
instrument approach.

The FMA itself is broken down into 5
columns which are generally for the
autothrust system (column 1), vertical
automation modes (2), lateral automation
modes (3), instrument approach
information (4), and finally engagement
status for the autopilot, flight director,
and autothrust system (column 5). The
diagram below expands the top portion of
the PFD to provide more detail on the
FMA itself.
Columns 1, 4 and 5 can be considered as status columns in that the information contained within is
mostly of a static nature. Columns 2 and 3, the vertical and lateral mode columns, undergo many
mode changes and the active mode is displayed on the top line in green text. The armed mode (the
mode that will replace the active mode when certain conditions are met) is displayed on the second
line usually in cyan text but in certain conditions, in magenta text. In certain landing conditions, the
vertical and lateral modes are combined into one mode that is displayed across both columns 2 and
3. Also shown are the fields for the flight control unit (FCU) selected speed and altitude. The colour
convention in general terms are green for active modes, cyan for armed modes or pilot selected
values, and white for automation status indications.

5. A320 FMA EXAMPLES
The following examples show different descent modes, and the manner in which the A320
alphanumeric FMA changes during a takeoff procedure and a CAT 3 autoland sequence. The
pictures are ordered vertically in columns within a page and are also numbered. A brief description
of each scene is contained under the picture.

5.1     Similar Descent Example
The following pictures show 4 different descent modes. These are managed descent, vertical speed
descent, flight path angle descent, and descent on the ILS GP. The four images do not form a
sequence, rather are shown as separate images to illustrate different descent modes. When viewing
the displays consider the chance of confusing different descent modes.




   1. Descent mode, idle thrust selected by autothrust       3. Manual flight following flight director with autothrust
 system, vertical mode active in speed hold with altitude    system engaged in speed mode. Flight director providing
capture at 5000‟ armed, lateral mode in navigation mode           guidance to specific flight path angle and track.
               (ie FMS), autopilot engaged.




                                                             4. Autopilot flight (1&2) with autothrust system engaged.
 2. Manual flight under flight director guidance, vertical    Autopilot tracking ILS glide slope and localiser signals,
  speed and heading hold guidance provided. Throttles                  cat 3 dual landing criteria established.
                   controlled manualy.
5.2     A320 Takeoff Example
The following sequence of pictures shows a normal takeoff, with acceleration segment, intermediate
level of at 3000‟, and climb to and level off at F250.




 1. Takeoff ground roll. Speed reference system active,        5. Climb becomes the active vertical mode, altitude
  climb mode armed; runway track active, nav armed;                     capture (FMS constraint) armed.
autothrust selected – TOGA, flight director 1 information
                        displayed.




                                                             6. Altitude hold active vertical mode, continued climb
                                                                           becomes the armed mode.
   2. Airborne through 35‟. Lateral navigation mode
                       engaged.




                                                            7. Climb the active vertical mode, altitude capture (cruise
                                                                       altitude) becomes the armed mode.
                 3. Autopilot 1 engaged.




                4. Climb power selected.                         8. Altitude hold in cruise active vertical mode.


5.3     Cat 3 Autoland Example
The following sequence of pictures shows a category 3 autoland approach from prior to ILS
interception to the end of the landing ground roll.




  1. Level at 2000, Autopilot autothrust engaged, flight       3. Intercepting glide slope and localiser. Approach
       director 1 displayed, speed mode selected.                     capability improved to CAT 3 DUAL.




  2. Approach mode armed (G/S and LOC armed), DH                      4. Tracking glide slope and localiser.
     selected, present approach capability indicated.
                5. Land mode active.                              8. Idle manually selected.




             6. Commencement of flare.                                9.Ground roll out.




           7. Autothrust reduction to idle.


6. GRAPHICAL FMA DESCRIPTION
The concept of display for the graphic FMA is to provide all of the relevant mode information in
one location on the PFD, rather than the current three locations (PFD, flight control unit, and multi-
purpose control display unit - Airbus). The current and the next significant automation modes are
displayed in a graphical format. The total display will represent a truth data summary on the current
operation of the aircraft and the intended course of action of the automation.

The information to be provided is that contained in the current Airbus FMA display, as well as the
currently commanded parameters such as altitude airspeed vertical speed or flight path angle, or
track heading or MCDU navigation. The engagement or otherwise of the autothrust, autopilot and
flight director is also presented. The following figure shows the general positional layout of items
within the proposed graphical FMA display.




When the lateral or vertical mode does not contain a significant next mode, as would be the case in
the cruise (altitude hold, and FMS navigation), these modes are presented graphically across both
the present and future mode fields.

6.1    Graphical FMA Schema
The following points briefly outline the concept of operation of the graphical FMA. A diagram
showing the icons to be used follows.
1. The displays are static images of the automation mode, not the relevant tracking
    performance of the aircraft. The various mode icons will not change relative position
    with changed tracking performance.
2. Intermediate modes such as localiser, glide slope, or altitude capture are not shown. The
    display shows the next major mode (ie localiser or glide slope track, or altitude hold) at
    the commencement of the capture process.
3. Three levels of automation are considered, normal, higher and lower.
4. Normal automation is based on flying with autopilot and autothrust systems engaged,
    and with matching FCU and FMS altitude constraints. Normal automation is presented
    in green. Icons associated with normal automation are displayed in green.
5. Lower automation involves basic autopilot functions such as V/S-Heading and FPA-
    Track, and manual control of the aircraft and throttles. Lower automation is presented in
    cyan.
6. Higher automation levels involved advanced features of the FMS (or MCDU) such as
    altitude constraints or geometric path descents not selected on the FCU. Higher
    automation is presented in magenta. Icons associated with higher automation modes are
    displayed in magenta.
7. The FCU selected speed and altitude values are displayed above the speed and altitude
    tapes in blue.
8. Airspeed is controlled via longitudinal pitch changes when idle is selected manually or
    by the autothrust system.
9. Airspeed is controlled via the autothrust system when an autothrust “SPEED” icon is
    shown. This indicates that the autothrust system is in speed mode and using variable
    thrust settings between idle and climb thrust to achieve a speed objective.
10. Managed speed is an automation pilot aid on Airbus aircraft in which the flight computer
    determines the appropriate speed for the given flight phase and configuration, and this
    speed is shown as a green dot on the PFD airspeed tape. When using managed speed, a
    green dot is shown at the top of the airspeed tape, and the airspeed in green above the
    aircraft icon.
11. Speed reference system (SRS) is a managed speed mode used after takeoff and during
    go-arounds in which the computer determines the appropriate speed for the
    configuration and weight. SRS is indicated above the aircraft when active.
7. GRAPHICAL FMA EXAMPLES
The following examples show different descent modes, and the manner in which the graphical FMA
will change during a takeoff procedure or a CAT 3 autoland sequence. The pictures are ordered
vertically in columns within a page and are numbered.

7.1    Similar Descent Example
The following pictures show 6 different descent modes. The „scenes‟ shown are not part of a
sequence, rather are shown as separate images to illustrate different descent modes. This sequence
has similar scenes to that displayed in section 5.1 above. The pictures are ordered vertically in
columns within a page and are numbered. When viewing the displays consider the chance of
confusing different descent modes.




 1. Autothrust engaged, idle selected; descent at constant      4. Autothrust engaged, variable thrust to maintain 250
250 (idle path descent) with altitude capture at 5000; FMS    selected by pilot. Manual flight from right sidestick, flight
lateral navigation. Autopilot 1 engaged, no flight director     director 1 displaying guidance for descent at constant –
                       information.                            3.3º flight path angle with no altitude capture, and lateral
                                                                               navigation as selected track.




  2. Autothrust engaged, variable thrust to maintain 250.
   Descent at constant 350 fpm ROD (repressurisation          5. Manual thrust, no speed target. Manual flight from left
 segment at top of descent) with altitude capture at 5000;    sidestick, flight director 1 displaying guidance for descent
  FMS lateral navigation. Autopilot 1 engaged, no flight       at constant 3300 fpm ROD with no altitude capture., and
                   director information.                                 lateral navigation is selected heading.




                                                              6. Autothrust engaged and holding 125 on ILS glide slope
 3. Autothrust engaged, variable thrust to maintain 250.      and localiser. Autopilots 1 and 2 engaged with cat 3 dual
Descent to achieve waypoint/altitude objective (geometric     approach criteria met. Flight director 1 information
 path descent) with altitude capture at 5000; FMS lateral     displayed.
   navigation. Autopilot 1 engaged, no flight director
                       information.
7.2     A320 Takeoff Example
The following sequence of pictures shows a normal takeoff, with acceleration segment, intermediate
level of at 5000‟, and climb to and level of at F250. This sequence matches the one displayed in
section 5.2 above.




 1. Takeoff roll. SRS armed vertical mode; runway track         5. Climb mode at airspeed 250 active vertical mode,
 active lateral, nav armed; autothrust selected – TOGA,                 altitude hold armed (FMS altitude).
       left pilot flying, flight director 1 displayed.




                                                               6. Altitude hold active (FMS altitude), continued climb
2. Airborne. SRS active, climb armed vertical mode; nav                                 armed.
                     active mode.




                                                                7. Climb mode at airspeed 290 active vertical mode,
                 3. Autopilot 1 engaged.                               altitude hold armed (cruise altitude).




          4. Thrust auto-reduced to climb thrust.                            8. Level at cruise altitude.


7.3      Cat 3 Autoland Example
         The following sequence of pictures shows a category 3 autoland approach from prior to ILS
         interception to the end of the landing ground roll. This sequence matches that displayed in
         section 5.3 above.




1. Level prior to ILS intercept. Autothrust engaged speed       2. Approach mode armed. G/S intercept/track armed
target 180 manually selected; altitude hold active vertical,   vertical mode; LOC intercept/track armed lateral mode.
  nav active lateral; autopilot 1 engaged, flight director 1
                   information displayed.
 3. Localiser intercept/tracking. Managed speed selected     7. Commencement of autoland flare.
   (green dot) computed target 140; LOC intercept and
                   tracking commenced.




                                                             8. Autothrust thrust reduction to idle.

4. Autopilot 2 engaged, Cat 3 dual approach criteria met.




                                                                   9. Idle manually selected.

   5. Glide slope intercept/tracking commenced. New
  managed speed target 125 (due configuration change)




                                                                      10. Ground rollout.


                6. Autoland criteria met.




Please complete the questions contained in the attached word file “FMA Survey-Questions.doc)” .
Complete survey return details are contained at the conclusion of the questions file. Please do not
return this file with your survey questions. (It over fills my yahoo inbox). Thank you for your time.

								
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