Review Questions - Engines, APU Flashcards
What are the primary differences between an automatic and a manual start?
a. Automatic Start - The FADEC provides full monitoring during start and will provide appropriate ECAM cautions and procedures to follow in the event of a start fault
b. Manual Start - Automatic start interruption and auto-crank are not available
When would you use a manual start?
After aborting a start because of:
a. Engine stall
b. Engine EGT overlimit
c. Low start air pressure
When expecting a start abort because of:
d. Degraded bleed performance due to hot conditions or at high altitude airports
e. Marginal pneumatic source
f. (A320) Intermittent ECAM ENG 1(2) IGN A(B)FAULT alert dring the first start of the day.
What controls the engines in all operating regimes?
FADEC
What functions does the FADEC control?
a. Control of gas generator
b. Protection against engine exceeding limits
c. Power management
d. Automatic engine starting sequence
e. Manual engine starting sequence
f. Thrust reverser control
g. Fuel recirculation control
h. Transmission of engine parameters and engine monitoring information to Flight Deck indicators
(Acronym anyone?)
Describe the redundancy of the FADEC
The FADEC system has two-channel redundancy, with one channel active and one in standby. If one channel fails, the other automatically takes control.
What is the power source for the FADEC?
a. The system has its own alternator making it independent of the aircraft electrical system when N2 is above a set value
b. If this alternator fails the FADEC automatically switches to aircraft electrical power
If the FADEC detects a fault during automatic start, is any crew intervention required?
No. The FADEC will (on the ground):
- close the HP valve
- close the start valve
- turn off ignition
- ensure an automatic dry crank cycle after the abort sequence in order to remove the fuel vapors
- control any additional start attempts
When does the Idle Control function of the FADEC system regulate idle speed?
Modulated Idle: Regulateed according to bleed system demand and ambient conditions.
Approach Idle: Regulated according to aircraft altitude, regardless of bleed system demand. Also selected in flt when flaps are extended and alows engines to accelerate rapidly from idle to go around thrust.
Reverse Idle: Reverse idle mode is slightly higher than forward idle thrust.
When will the FADEC abort a start?
On the ground:
a. Hot start
b. Hung start
c. Stalled start
d. No light up
e. Low start air pressure,
f. Starter time exceeded
g. Thrust lever not at idle
How is the IDG cooled?
IDG fuel/oil heat exchanger
How many igniters fire on an in-flight start attempt?
Both A and B
How many igniters fire during a manual start?
Both A and B
When does continuous ignition automatically operate?
a. Engine flameout detection
b. Failure of the Engine Interface Unit (EIU)
c. If there is an ignition delay during engine starting
What is the active range of the A/THR?
a. Just above IDLE to the CL detent (2 engines)
b. Just above IDLE to the MCT detent (1 engine)
What determines the maximum thrust the A/THR system will be able to command?
The position detent of the thrust lever
