# Aviation Flow Chart by mme12188

VIEWS: 38 PAGES: 112

• pg 1
```									        PPC Requirements
 AR 95-1, para 5-2a tells us that the
aviator will evaluate:
 Aircraft performance
 Departure, enroute, and approach data
 Notices to Airmen (NOTAM)

 DA Form 5701-R may be used as an aid
to organize performance planning data
required for the mission
PPC Requirements
 This   form will be used for:
 RL  progression training
 Annual ATP evaluations
 When required during other training and
evaluations
 Forevaluation flights, the evaluator will
determine the blocks that will be filled
out
 Be   safe and do it all
PLANNING CONDITIONS
   CURRENT                 MAXIMUM
 PA = 2500 ft MSL        PA = 3000 ft MSL
 FAT = 25 deg C          FAT = 30 deg C
 GWT = 15000 lbs
 ETF #1 = 1.0          CRUISE
 ETF #2 = .98            PA = 6000 ft MSL
 FAT = 25 deg C
Engine Torque Factor
 ETF
 The  comparison of an individual engines
torque available to a specification engines
(1.0 ETF) torque available at a reference
temperature of 35 deg C
 The ETF must be between .85 to 1.0
 The ETF indicates degradation of
performance based on engine usage
Aircraft Torque Factor
 ATF
 ATF  is the average of the two ETF’s. It
indicates the aircraft’s total performance
capability based on the condition of the two
engines.
 ATF is also based on 35 deg C and is allowed
to range from .90 to 1.0
 If ATF is outside this range do not fly the
aircraft
2500/3000        25/30         15000

.99     1.0   .98

6000        25
Torque Ratio
 TR
 Torque  factor chart indicates improved
engine and aircraft performance as
temperature decreases below +35 deg C
 Torque ratio will be written to three decimal
places
 Three instances when chart is not needed:
• If FAT is +35 degrees or above
• If FAT is -15 or below
• If ETF is 1.0
Chart Info
Torque Factor
100% RPM R
Page 7A-7

.982
Chart Info
Torque Factor
100% RPM R
Page 7A-7

.984
2500/3000        25/30          15000

.99     1.0    .98
.991     1.0   .982

6000        25

.992    1.0    .984
Max Torque Available
 This torque value represents the
maximum specification torque available
at zero airspeed and 100% RPM R for
the operational range of PA and FAT
 This value may or may not be continuous
due to Chapter 5 limitations
Max Torque Available
 The  actual MTA figure should be
annotated on the PPC, regardless of
whether it is above the continuous torque
limits
 Conditions may arise when the pilot may
need transient power demands
 The pilot is responsible for ensuring that
Chapter 5 transient limits are applied
when using this value, if applicable
Max Torque Available
 Based on flight test data, the MTA chart
reflects the maximum torque the engines
can produce without exceeding the
maximum of any of your three 30 minute
engine operating limits:
 TGT  = 851 deg C
 Ng = 102%
 Engine Oil Temperature = 150 deg C
Max Torque Available
 MTA    is limited by the HMU through Ng
limiting
 A TGT limiter circuit within the DEC
causes the HMU to limit fuel to the Ng
engine section when TGT reaches 866 +/-
6 deg C (dual engine) and 891 +/- 5 deg C
(single engine)
Max Torque Available
 TGT   limiting is what will most commonly
limit MTA for the PA and FAT
combinations that most aviators operate
in
 The HMU also limits fuel to the Ng
section during high ambient temperature
conditions
Max Torque Available
 At high ambient temperatures, the air
becomes less dense, causing the Ng
turbine section to operate at higher
speeds in order to deliver the same
volume of air output to the power turbine
wheels (Np)
 Fuel flow is limited to prevent excessive
operating speeds that could damage the
Ng turbine wheels
Max Torque Available
 The  HMU also limits fuel flow to the Ng
section during very cold conditions
 Mach speeds decrease as temperature
decreases
 This limiting is to prevent compressible
air flow (mach speeds) from occurring
within the compressor inlet section
Max Torque Available
 IfMTA is more than 100% dual engine
(above 80 KIAS), 120% dual engine (80
KIAS or less), or 135% single engine,
then the aircraft is structurally limited
 The engines are capable of producing the
power, but components in the
transmission (main module for DE
torque and input modules for SE torque)
are incapable of sustaining these torque
Max Torque Available
 In a structurally limited aircraft,
attempting to operate continuously above
the allowable torque value in Chapter 5
will result in structural damage to the
transmission
 Maximum torque for a structurally
limited aircraft is limited to a 10 second
time limitation
Max Torque Available
 IfMTA is below 100% dual engine
(above 80 KIAS), 120% dual engine (80
KIAS or less), or 135% single engine,
then the aircraft is environmentally
limited
 Due to environmental conditions the
engines are incapable of producing
maximum rated power and transmission
torque limits will not be reached
Max Torque Available
 In an environmentally limited aircraft,
attempting to demand more torque than
MTA, will result in rotor bleed-off
 Depending on how far the collective is
increased beyond this point, will
determine how far the rotor will droop
 The larger the excursion, the greater the
reduction in rotor
 The bigger the splat mark
Max Torque Available
 Itis important to understand what the
pilot will observe on the torque gauges
when maximum power is demanded
 One scenario would be an aircraft with
identical ETF’s, resulting in identical
MTA values for both dual and single
engine operations
Max Torque Available
 After  doing our planning we find out that
out Dual Engine MTA is 114%
 When MTA is demanded the pilot would
observe 114% torque on both the #1 and
#2 engine torque gauges
 The respective TGT for each engine would
be at the dual engine limiting value (866
+/- 6)
 TGT limiting would prevent the pilot from
receiving more torque
Max Torque Available
A  more common scenario would be
having different ETF’s (1.0 and .948)
resulting in a different MTA for each
engine
 In this situation when MTA is demanded,
the pilot would not see 114% on the
torque gauges, as this is only an averaged
number between the two engines
 As the pilot demanded power, torque on
both engines would rise evenly to 108%
Max Torque Available
 At  this time the #2 engine would reach
it’s TGT limiter and would remain at
108% torque
 If the pilot continues to demand more
power, the stronger 1.0 engine would
produce up to 114% before reaching it’s
TGT limiter
Max Torque Available
 The  pilot would observe 114% and 108%
respectively, with TGT on both engines at
the dual engine limiter
 Attempting to demand more power in
this case would result in rotor bleed-off
 A torque split will be induced by the pilot
when power demanded exceeds that of
the weakest engine
 This is considered normal
Max Torque Available
 With bleed-air extracted, adjust MTA as
follows:
 Eng. Anti-Ice On - Subtract 18% from MTA
 Heater On - Subtract 4% from MTA
 Both On - Subtract 22% from MTA

 Thiswill hold true for SE MTA except
the values are half of that stated
Max Torque Available
 These  values are different for different
helicopter models
 See the -10 for the values for the UH-60A
 Also see the -10 if HIRSS is installed and
baffles removed
 This is not a normal configuration
Chart Info
Max TQ Avail
10 Min Limit
Bleed Air Off
100% RPM R
Zero Airspeed
Page 7A-10

112%
Chart Info
Max TQ Avail
30 Min Limit
Bleed Air Off
100% RPM R
Zero Airspeed
Page 7A-11

95%
2500/3000          25/30             15000

.99        1.0     .98
.991         1.0    .982
111       112     110

Spec Torque - 112%                112 X .982 = 110
Spec Torque - 95%                 112 X .991 = 111
95 X .984 = 93
1/2 MTA = 46%                        95 X .992 = 94

6000           25

.992        1.0     .984
94         95      93
Max Allowable GWT
OGE/IGE
 This  is the most weight the aircraft is
able or allowed to pick up to a 10’ hover
height for IGE operations or to an OGE
altitude (70’ for UH60) for OGE
operation
 This weight is limited by either engine
capability or aircraft structural design
Max Allowable GWT
OGE/IGE
 The Max GWT for UH60A without
provisions for Engine Output Shaft
STUD BALANCE MWO or without the
wedge mounted pitot static probes is
20,250 lbs
 The Max GWT for UH60L or UH60A
with the MWO provisions and wedge
mounted pitot static probes is 22,000 lbs
Max Allowable GWT
OGE/IGE
 If the Max GWT IGE or OGE is
20,250/22,000 lbs (as applicable), then
 Although the engines may be capable of
lifting more weight, the airframe is not
 When the Max GWT value is
20,250/22,000 lbs, attempting to operate
at a weight above that value will result in
exceeding a structural design limitation
and airframe damage is likely
Max Allowable GWT
OGE/IGE
 If the Max GWT IGE or OGE is less than
20,250/22,000 lbs (as applicable), then
 Although the airframe is capable of
lifting up to the Chapter 5 limit, the
engines cannot provide enough power to
lift that weight for the given
environmental conditions
Max Allowable GWT
OGE/IGE
 When   the Max GWT value is less than
20,250/22,000 lbs, attempting to operate
at a weight above that value will result in
rotor droop (environmental limitation),
but no airframe damage should result
 Unless you crash from low rotor RPM!
Chart Info
Hover
Clean Config.
100% RPM R
Zero Wind
Page 7A-15

21,250 lbs
2500/3000        25/30                 15000

.99       1.0      .98
.991      1.0      .982
111       112     110
21250/22000

6000        25

.992      1.0     .984
94        95      93
GO/NO GO Torque OGE/IGE
 This  value is essentially a weight check
 At a 10’ hover height, this is the torque
that will determine if you are at or below
your maximum weight that the engines
are capable of lifting to an IGE or OGE
altitude
 Bottom line…GNG is the hover torque
for Max Allowable GWT for the day
GO/NO GO Torque OGE/IGE
 If your Max GWT OGE is at the Chapter
5 maximum (ie. 20,250/22000), then only
one GNG value will be needed and this
will represent both IGE and OGE
capability
 If you can lift maximum weight to OGE
altitudes, then you can obviously do it at
IGE altitudes
GO/NO GO Torque OGE/IGE
 Inthis scenario, if the torque required to
maintain a stationary hover is at or below
the GNG IGE/OGE value, the pilot has
confirmed aircraft weight to be at or
below Max GWT and any maneuver
requiring OGE power or less may be
attempted
GO/NO GO Torque OGE/IGE
 If the torque required to maintain a
stationary hover is above the GNG
IGE/OGE, you cannot operate in
compliance with the -10 because you are
exceeding the aircraft’s maximum
structural gross weight
 This requires an entry to made to DA
Form 2408-13
 The helicopter shall not be flown until
corrective action is taken
GO/NO GO Torque OGE/IGE
 If your Max GWT is less than the
Chapter 5 maximum (20,250/22,000),
then a GNG value is required for both
IGE and OGE
 If the torque required to maintain a
stationary hover exceeds the GNG OGE,
but does not exceed the GNG torque
IGE, then only IGE maneuvers may be
attempted
GO/NO GO Torque OGE/IGE
 Maneuvers    requiring OGE power are:
 Perform fast rope insertion
 Perform rappelling procedures
 Perform rescue-hoist operations
 Perform STABO operations

 Basically, if it hangs under the aircraft
don’t do it
GO/NO GO Torque OGE/IGE
 Theoretically,if the torque required to
hover exceeds the GNG OGE, you should
not be able to exceed the GNG IGE for
and environmentally limited aircraft since
rotor bleed off will develop when engines
hit the TGT limiter at 866 +/- 6
GO/NO GO Torque OGE/IGE
 Remember,    all hover checks are done at
an altitude of 10’
 If you are performing external load
operations plan a GNG value that will
place the load at 10’ AGL (usually 30’ or
40’)
GO/NO GO Torque OGE/IGE
 GNG    is computed using maximum
forecast conditions
 When the actual temperature is less than
maximum, the torque required to hover
at a given GWT is less
 To ensure that OGE capability exists
and/or structural limitations are not
exceeded, reduce GNG by 1% for each
10C that actual temperature is less than
maximum forecast
GO/NO GO Torque OGE/IGE
 The  colder temperatures would allow the
same 20,250/22,000 pound aircraft to
hover at these weights with less torque
 Therefore operating at the higher
(original) GNG torque value would mean
you are actually hovering an aircraft
weighing more than the Chapter 5 limits
allowed
Chart Info
Hover
Clean Config.
100% RPM R
Zero Wind
Page 7A-15

92%
Chart Info
Hover
Clean Config.
100% RPM R
Zero Wind
Page 7A-15

96%
2500/3000        25/30                 15000

.99       1.0      .98
.991      1.0      112
111       112     110
21250/22000
92/96

6000          25

.992        1.0     .984
94         95      93
Predicted Hover Torque
 With current conditions at takeoff, and at
takeoff GWT, this is the estimated torque
required for a stationary 10’ hover in
zero wind conditions
 For external load operations, record the
predicted torque required to hover at a
height that will place the load at 10’ AGL
(usually 30’ or 40’)
Predicted Hover Torque
 Ifactual hover torque does not agree
with predicted hover torque it is not a
non-flying condition
 As long as you are still below GNG OGE
or IGE you may still fly
Predicted Hover Torque
 Oneof the following conditions has
occurred:
 Your  actual weight is more or less than you
predicted
 Current conditions have changed since you
computed your PPC (FAT, PA, GWT, Wind,
etc.)
• Remember, your hover values are based on a no
wind condition
error was made during computation of
 An
PPC
Chart Info
Hover
High Drag
100% RPM R
Zero Wind
Page 7A-16

58%
2500/3000        25/30             15000

.99        1.0    .98
.991       1.0    .982
111       112     110
21250/22000
92/96
58

6000         25

.992       1.0    .984
94        95      93
Velocity Never to Exceed (Vne)
 The  maximum permitted airspeed as a
function of temperature, pressure
altitude, and aircraft weight
 Exceeding this airspeed may cause the
rotor system to encounter the effects of
 Stall has not been encountered in one G
flight up to the airspeeds shown on the
Vne chart in the -10
Velocity Never to Exceed (Vne)
 Exceeding  this airspeed may also cause
and colder), and/or aircraft structural
damage
 This airspeed cannot be obtained in level
flight
Velocity Never to Exceed (Vne)
 If Vne minus 15 KIAS is a lesser value
than MAX RANGE IAS, this lower value
will be the recommended maximum
turbulence penetration airspeed
 The 15 knot speed reduction reduces the
likelihood of the pilot exceeding Vne due
to airspeed fluctuations associated with
turbulence
Chart Info
Airspeed
NO ESSS
100% RPM
Page 5-14

180 KIAS
2500/3000        25/30                 15000

.99        1.0    .98
.991       1.0    .982
111       112    110
21250/22000
92/96
58

6000          25               180

.992        1.0     .984
94         95      93
Cruise Speed IAS/TAS
 These airspeeds are dictated by the
mission or chosen by the pilot within
aircraft limits
 Indicated airspeed is the airspeed shown
on the pitot static airspeed indicator that
has been calibrated for standard sea level
pressure and is uncorrected for airspeed
system errors
Cruise Speed IAS/TAS
 Calibrated   airspeed is the indicated
airspeed corrected for position and
instrument error
 Calibrated airspeed would be equal to
true airspeed (TAS) at standard pressure
at sea level
 The error is usually small and may be
computed with reference to the -10
Cruise Speed IAS/TAS
 TAS   is calibrated airspeed corrected for
error due to density altitude
 Since the airspeed indicator is calibrated
for the dynamic pressures corresponding
to airspeeds at sea level conditions,
variations in air density must be
accounted for
Cruise Speed IAS/TAS
 When   determining the IAS to be used for
the PPC, the pilot should use the speed
that the aircraft will be at for the
majority of the flight profile
 When determining single engine (SE)
cruise speed, the pilot has the option of
choosing any speed that falls within the
MIN/MAX SE envelope.
Cruise Speed IAS/TAS
 The pilot may wish to consider using at
least 80 KIAS or higher. 80 KIAS
provides the minimum rate of descent for
autorotation and would ensure sufficient
airspeed available to arrest the rate of
descent should the other engine become
inoperative
Cruise Speed IAS/TAS
 Autorotative   decelerations initiated at
speeds below 80 KIAS will most likely
result in aircraft damage
 Although it will not always be possible,
an airspeed should be used that will
maintain cruise flight at or below your
continuous torque available SE
 Torques above your continuous value will
limit you to 30 minutes of operation if
that power setting is maintained
Chart Info
Cruise
Clean Config
6000ft. PA
30 deg C
Page 7A-60
115 KTAS
Chart Info
Cruise
Clean Config
6000ft. PA
30 deg C
Page 7A-60

96 KTAS
2500/3000        25/30                15000

.99          1.0     .98
.991         1.0     .982
111          112     110
21250/22000
92/96
58

6000         25                180

.992       1.0     .984
94         95      93
100    115   80       96
Cruise Torque
 Thisis the torque required to maintain
the Cruise Speed (IAS or TAS) that you
have selected for the mission
Chart Info
Cruise
Clean Config
6000ft. PA
30 deg C
Page 7A-60

44%
Chart Info
Cruise
Clean Config
6000ft. PA
30 deg C
Page 7A-60

38 X 2 = 76%
2500/3000        25/30                15000

.99          1.0    .98
.991         1.0    .982
111           112    110
21250/22000
92/96
58

6000         25               180

.992        1.0    .984
94           95     93
100    115    80      96
44           76
Cruise Fuel Flow
 This  is the predicted fuel flow (burn rate)
that the aircraft will have at Cruise
Torque
 With bleed-air extracted, adjust fuel flow
as follows:
 Eng. Anti-Ice On - Add 100 lbs/hr
 Heater On - Add 12 lbs/hr
 Both On - Add 112 lbs/hr
Cruise Fuel Flow
 This will hold true for SE MTA Fuel
Flow except the values are half of that
stated
 These values are different for different
helicopter models
 See the -10 for the values for the UH-60A
 Also see the -10 if HIRSS is installed and
baffles removed
 This is not a normal configuration
Chart Info
Cruise
Clean Config   775 lbs/hr
6000ft. PA
30 deg C
Page 7A-60
Chart Info     1100/2 = 550 lbs/hr
Cruise
Clean Config
6000ft. PA
30 deg C
Page 7A-60
2500/3000        25/30                 15000

.99            1.0    .98
.991           1.0    .982
111          112     110
21250/22000
92/96
58

6000          25               180

.992        1.0    .984
94          95    93
100     115    80      60
44             76
775             550
Continuous Torque Available
 This is the most torque the engines can
produce and remain out of all of your 30
minute engine operating limits
 You will be at the top of one or more of
 TGT  - 810C
 NG - 99%
 Eng Oil Temp - 135C
Continuous Torque Available
 As far as pre-mission flight planning, this
torque value is pretty limited in it’s
application
 A more practical value would be a
continuous airspeed which could be used
for determining times enroute and flight
plan speeds
Continuous Torque Available
 As  a technique, the pilot may obtain a
continuous airspeed by tracing the
Continuous Torque available line upward
until you intersect your aircraft GWT
 Read horizontally to indicated airspeed
 This will provide the pilot with a speed
value to fly as quickly as possible to
his/her destination, while remaining
outside of any 30 minute limits
Continuous Torque Available
 Notice  that unlike the ATF lines, there is
only one Continuous Torque line on your
cruise charts
 The Continuous Torque line in the cruise
chart represents an averaged ATF of .95
or greater
 If the aircraft ATF is lower than .95, the
Continuous Torque value will be less
than the PPC indicates, but we have no
means to compute how much less
Continuous Torque Available
 Notice  also that the Continuous Torque
line stops at approximately 70-80 KIAS
 For torques below these speeds, read
vertically down from where the
Continuous Torque line terminates to
obtain this value
 DO NOT interpolate below the line
Continuous Torque Available
 Both  the Continuous Torque and ATF
lines are slanted to the right as you move
upward
 This is to show the increase in torque
produced by the engines as the aircraft
increases speed
 With faster speeds, each engine intake
will receive a larger volume of air per
unit of time to work on, which results in
more power output available
Continuous Torque Available
 Notice  also, the PA and Temp
combination of 30C and zero feet PA
shows that the Continuous Torque line
disappears off the cruise charts
 This is because when operating in colder
temperatures, the 100% Dual Engine
Torque limit will be reached before the
engines enter a 30 minute limit
 Continuous Torque available will then be
the same as MTA
Continuous Torque Available
 The  pilot should be aware that operating
while bleed-air is being extracted from
the engines will result in a lower
Continuous Torque Available value than
shown on the PPC
 When bleed air is taken from the engines,
they operate less efficiently and result in
higher turbine temperatures to produce
the same amount of torque as without
bleed air usage
Continuous Torque Available
 Just  as MTA is reduced with bleed air
extracted , Continuous Torque Available
is also going to be lower due to reaching
the Continuous TGT value earlier (810C)
 The -10 or ATM does not discuss this
situation, but the pilot may want to
consider subtracting the applicable
torque for heater and/or anti-ice
operation when in use
Chart Info
Cruise
Clean Config
6000ft. PA
30 deg C
Page 7A-60

81%
Chart Info
Cruise
Clean Config
6000ft. PA
30 deg C
Page 7A-60

80%
2500/3000        25/30                 15000

.99            1.0     .98
.991           1.0     .982
111           112     110
21250/22000
92/96
58

6000          25                180

.992        1.0    .984
94         95     93
100     115    80     96
44             76
775            550
81             80
Max Endurance IAS
 Max   Endurance IAS is based on drag
data
 This figure correlates to the maximum
lift to drag ration (L/D max) and will
result in the most aerodynamically clean
airspeed for flight at a given GWT and
environmental condition
Max Endurance IAS
 Max   Endurance will allow you to fly
straight and level for the longest period
of time (time aloft) due to the lowest fuel
burn rate
 This airspeed will produce Max
Endurance only when operating at a
torque value that provides level flight
 This associated torque value can be
derived off the cruise chart is desired
Chart Info
Cruise
Clean Config
6000ft. PA
30 deg C
Page 7A-60

62 KIAS
2500/3000        25/30                 15000

.99             1.0     .98
.991            1.0     .983
111           112     110
21250/22000
92/96
58

6000          25                180

.992        1.0    .984
94          95     93
100     115    80     96
44              76
775             550
81             80
62
Max Range IAS
 This is the airspeed which will take you
the farthest distance for a given amount
of fuel
 This is the best miles per gallon airspeed
under zero wind conditions
 This airspeed can also be used as
Turbulence Penetration Airspeed
provided it is less than Vne minus 15
knots
Max Range IAS
A   method of estimating Max Range IAS
in winds is to increase Max Range IAS by
2.5 knots for each 10 knots of effective
headwind (which reduces flight time and
minimizes loss in range)
 You can also decrease Max Range IAS by
2.5 knots for each to knots of effective
tailwind due to economy
Chart Info
Cruise
Clean Config
6000ft. PA    122 KIAS
30 deg C
Page 7A-60
2500/3000        25/30                 15000

.99            1.0     .98
.991           1.0     .982
111          112     110
21250/22000
92/96
58

6000          25                180

.992        1.0    .984
94         95     93
100     115    80     96
44             76
775            550
81             80
62
122
Single-Eng Capability IAS
(MIN/MAX)
 These  are the minimum and maximum
airspeeds possible without losing altitude
with a single engine operating
 Operating between these airspeeds will
maintain RPMR within limits
 If the derived airspeed is less than 40
KIAS, the airspeed indicators will be
unreliable
Single-Eng Capability IAS
(MIN/MAX)
 Ifthe derived airspeed exceeds 130 KIAS
the SE max airspeed is still 130 KIAS
 Remember that the accuracy of these
values depends on which engine becomes
inoperative
 These figures are based on your lowest
ETF engine operating and at takeoff
GWT
Chart Info
Cruise
Clean Config
6000ft. PA
30 deg C
Page 7A-60    25 to 106 KIAS
2500/3000        25/30                 15000

.99            1.0     .98
.991           1.0     .982
111          112      110
21250/22000
92/96
58

6000         25                180

.992         1.0      .984
94         95       93
100     115    80        96
44                76
775               550
81               80
62
122
25     106
Max Allowable GWT
Single Engine
 Thisis the maximum amount of weight
the remaining engine is capable of
powering for level flight
Chart Info
Cruise
Clean Config
6000ft. PA
30 deg C
Page 7A-60

19,000 lbs
2500/3000        25/30                 15000

.99            1.0     .98
.991           1.0     .982
111          112     110
21250/22000
92/96
58

6000          25                180

.992        1.0    .984
94         95     93
100     115     80     96
44             76
775            550
81             80
62
122
25   106
19,000
Arrival Data
 Arrival  data will be computed when the
conditions differ significantly from
departure conditions
 This is defined as an increase of:
 10degrees C in FAT
 2000 ft PA
 1000 lbs GWT

 Complete    data on your own
 6000   PA, 25 FAT, 14000 GWT
6000    25                  14000

.99       1.0     .985
100      101     99
19,500/22,000
54
62
Recomputation of PPC Data
 PPC  will be recomputed whenever a
significant change in the mission’s
conditions occurs as discussed earlier
QUESTIONS??

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