Powerplant and APU Limitations Flashcards
What is the maximum TGT for Engine Start ?
740 deg C (max 2 sec)
What is the maximum TGT during engine relights ?
780 deg C (max 2 sec)
What is the maximum engine limitations for takeoff ?
N1
N2
TGT
N1 - 95.5%
N2 - 103.5%
850 deg C (5 min)
Time Limit = 5 mins (2 Engine)
10 Mins (1 Engine)
(in case of engine failure after take off may be extended to 10 min)
What is the maximum engine continuous operating limits ?
N1
N2
TGT
N1 - 95.5%
N2 - 100.5%
TGT - 795 deg C
Time Limit = Unrestricted
What is the maximum engine overspeed limits ?
N1
N2
N1. - 98.3%
N2. - 106.6%
(Both max 20 seconds)
What is considered the minimum engine N2 idle speed to consider an engine stabilised ?
N2. - 47.9%
What is the maximum engine limitations for reverse thrust ?
N1
N2
TGT
N1. - 95.5%
N2. - 99.2%
850 deg C
Time Limit = 60 seconds
ADDITIONAL - To avoid high fan blade stresses, stabilized operation in the restricted range
What is the engine N1 restricted range ?
57 - 75 % N1
What is the engine minimum oil pressure for takeoff ?
30 psi
What is the minimum engine oil pressure in flight ?
Is variable -
Low idle - 16 psi
78 % N2 - 25 psi
What is the minimum engine oil temp for engine starting ?
Minus 50 deg C
What is the engine minimum oil temp before increasing power following engine start ?
Minus 30 deg C
What is the engine maximum oil temp (Unrestricted) ?
105 deg C
What is the engine maximum transient oil temperature ?
120 deg C
(15 minute max)
Flex thrust take off shall not be used when the any of the following conditions are present (9 items) :
- Icing conditions exist
- Contaminated runway
- Wind shear or inversion
- Lift dumpers inop
- Anti skid inop (any)
- Wing anti ice on
- Tail anti ice on
- No means established to periodically verify rated thrust
- Items affecting performance cause significant increase in crew workload.
What is the maximum APU load at the following altitudes ?
Sea level
15000 ft
25000 ft
35000ft
Sea level - 100 %
15000 ft - 100%
25000 ft - 65 %
35000 ft - 30 %
What is the engine maximum fuel temperature (unrestricted) ?
95 deg C
What is the engine maximum fuel temperature (limited to 15 minutes) ?
(transient)
130 deg C
What is the limitation on APU start cycles ?
3 consecutive starts with 2 min between starts
What is the time limit before shutting down the APU ?
Allow 70 seconds before switching off the batteries, unless external AC power is available
What is considered the required bleed pressure to start engines ?
- APU
- Cross Bleed
- External Air
- APU- 25 PSI to 35 PSI (can be as low as 20 PSI up to 8000ft)
- Cross Bleed- 30 PSI
- External Air - 30 PSI to 50 PSI
What is the engine warm up time required based on start oil temperature ?
Oil temp 40 or above - 2 mins
Oil temp 20 - 40 - 3 mins
Oil temp 20 & below - 4 mins
What is the time required at idle thrust before engine shutdown ?
1 min (Engine oil returns after 15 mins)
What should be considered the maximum oil consumption per hour ?
1.5 L / HR
What is the maximum IAS below 10,000 ft in the event of a window heat failure ?
300 KIAS below 10000 FT
What is the maximum altitude start for the APU (Both R and RR) ?
R Type = FL310
RR Type = FL350
(For an R Type APU if it is cold soaked start is not guaranteed above FL
What is the maximum over temperature limitation ?
870 ºC for 20 seconds
What are the limitations on the engine starter ?
4 attempts, 2 mins max, 30 seconds off
15 mins off after 4th attempt
(Must light up within 20 seconds of fuel lever open)
What is considered the minimum oil pressure to complete a flight ?
16 - 25 psi
