Powerplant Flashcards
What type of engines are in the 900? 700?
CF34-8C5
CF34-8C5B1
How many stages does the N2 axial flow compressor have?
10
How many lbs of thrust at full power?
13,560 lbs
How many lbs of thrust does the APR provide?
14,750 lbs
Where do the thrust reversers draw air from?
Bypass air
N1: ___ stage low pressure turbine drives the fan blades?
4
N2: ___ stage high pressure turbine drives the 10 stage axial flow compressor, combustor, accessory gear box?
2
N2 gearbox consists of?
(FISH OIL)
- Engine FUEL pump & fuel metering unit (FMU)
- IDG
- Air turbine STARTER (ATS)
- HYDRAULIC pump (EDP1, EDP2)
- Engine OIL lubrication pumps
- FADEC
- Integral oil reserve
What % of the thrust does the bypass air create?
80%
What actuates the VG (Variable Geometry) compressor linkage?
Fuel
FMU
Fuel Metering Unit
What runs the FMU?
FADEC
Are thrust levers mechanically or electrically actuated?
Electrically
What does the VG system regulate?
Airflow, by changing position of inlet guide & stator vanes
High Pressure Turbine drives what?
Compressor
Low Pressure Turbine drives what?
Fan
Fuel scheduling is controlled by?
FADEC
What are FADEC’s 2 channels in the Dual Channel Computer?
- In control
- Standby
How often do the dual channel FADEC computers alternate roles?
Every second flight
FADEC alternator supplies power to both channels when N2 is > ___?
50%
What powers FADEC when N2 is < 50%?
Aircraft’s electrical system
How many N2 idles does FADEC program?
What are they?
5
- Flight idle
- Approach idle
- Landing idle
- Reverse idle
- Ground idle
What are the 3 sub-systems FADEC controls the engines with?
- Fuel control
- Compressor airflow management
- Engine starting/ignition control
Left & Right engines’ FADEC computers share info through what?
Cross-Talk Data Bus
N2 “Approach Idle” allows what?
Acceleration to TOGA thrust in min. time
How long does FADEC maintain Landing Idle?
5 seconds
MCT
Max Continuous Thrust
What does FADEC do if an engine failure occurs in the “Cruise” detent?
Increase operative N1
At what % difference will FADEC increase power on the operating engine?
N1 >= 15%
When does APR arm for takeoff?
When N1 is within 8% of scheduled takeoff power
When in the “Climb” detent on a single engine, how much thrust is provided?
MCT
Continuous Ignition must be used during:
- TO/LDG on contaminated runway
- Flight through moderate/heavy rain
- Flight through moderate/heavy turbulence
- Flight in vicinity of t-storms
When would you receive “L(R) AUTO IGNITION” advisory message?
FADEC detects a flameout
When would you receive”L(R) ENG FLAMEOUT” caution message?
N2 falls below relight envelope
What does FADEC automatically select at Stick Shaker?
CONT IGNITION
Bleed air manifold can be pressurized by:
- APU
- Crossbleed
- External air cart
ATS
Air Turbine Starter
What does the Start Valve require to open?
28V DC & pneumatic pressure
When does FADEC stop powering the Starter Motor?
50% N2
Start sequence: When “Start” switchlight is pressed:
- Isolation valve opens
- Start valve on associated engine opens
- White START switchlight illuminates
- L or R ENGINE START status message displayed
- 50% N2 rpm
- Starter disengages
Bleed air extracted from 6th & 10th stage provide pneumatic services for:
- Wing/Cowl anti-ice
- Air-conditioning/Pressurization
- Cross-bleed engine starts
ACSC
Air-Conditioning System Controllers
ACSC controls what?
Bleed-air selection (6th or 10th)
The 3 thrust lever detents:
- Climb
- TOGA
- Max Power
If uncommanded deployment of thrust reverser occurs, FADEC commands:
- Reverser to close
- Idle RPM on affected engine
Max usable oil?
7.2 quarts
Max allowable rate of oil consumption?
.05 GPH
Max duration without engine oil servicing?
36 hours (if not checked, level must be checked 3 minutes to 2 hours after each engine shutdown)
When does L(R) OIL LEVEL LO status message display?
- Engines operating: <80%
Oil Temp Limitations:
- Min for Starting
- Max Continuous
- Max Permissible (15 min. max)
-40 C
+155 C
+163 C
Max oil refill without motoring?
2 quarts
Before introducing fuel, ITT must be <:
- Ground
- Airborne
- 120 C
- 90 C
Define Cold-Soaked?
-30 C+ for > 8 hours
What must be done before a cold-soaked airplane can be started?
- Dry motor for 60 seconds
- Reversers deploy & stow w/in 2 seconds
Start Sequence:
N2 - 20% ITT - <120 C Right Thrust Lever.....ADVANCE TO IDLE Engine Instruments....CHECK Starter cutout (EICAS) N1 - 20-25% ITT - 450-600 C N2 - 56.5-68.0%
N2 split at ground idle max %?
2%
Max ambient temperature for TO/LDG?
+35 ISA
Min ambient temperature for TO/LDG?
-40 C
Max altitude for windmill start?
21,000 ft
What allows 10th stage bleed air availability?
ACSC (Air Conditioning System Control)
What is the psi required for a cross-bleed start?
42 psi to a max of 80% N2
When will APR arm for takeoff?
Engine speed within 8% of scheduled takeoff power
How can you tell if APR is armed?
APR ARMED advisory message
When will APR activate
- thrust levers in TOGA or MAX POWER detent
- N1’s differ by >=15%
How will we know APR has been activated?
Green APR icon on operable engine N1 gauge
What occurs during thrust reverser deployment?
translating cowls move aft
bypass air is redirected through cascade vanes
What indication will be seen with normal thrust reverser deployment?
Green REV icon on N1 gauge
What happens when a thrust reverser inadvertently deploys?
FADEC commands reverser to close & thrust set to idle on affected engine
What are the indications of inadvertent thrust reverser deployment?
Amber REV icon on N1 gauge
REV UNLOCKED caution message
Where is the high-pressure air/ground connection located?
Under left engine nacelle
