Engines Flashcards
What are the primary differences between an automatic and manual start?
AUTOMATIC: Fadec provides full monitoring during start and will provide appropriate ECAM cautions and procedures to follow in the event of a start fault
MANUAL: Automatic start interruption and auto-crank are not available
When would you use a manual start?
After aborting a start because of:
-Engine stall
-Engine EGT overlimit
-Low start air pressure
OR
When expecting a start abort because of:
-Degraded bleed performance due to hot conditions or high alt airports
-An engine with a reduced EGT margin in hot conditions or high alt airports
-Marginal performance of the external pneumatic power group
What controls the engines in all operating regimes?
FADEC (Full authority digital engine controls)
What functions does the FADEC Control?
-Fuel metering
-Engine limits based on thrust lever angle
-Start sequencing
-Provides engine indications and thrust limit displays on the E/WD
What redundancy does FADEC Have?
Dual Channel- One is active while the other is on standby
When does continuous ignition automatically operate?
Engine flameout detection
Failure of the EIU (Engine interface unit)
How many ignitors fire on a manual or in-flight starts?
Both A and B
What is the power source for the FADEC?
The System has its own alternator making it independent of the aircraft electrical system when N2 is above a set value
If this alternator fails, the FADEC automatically switches to aircraft electrical power
When will the FADEC abort a start?
Hot start, Stalled start (Hung) and no ignition
If the FADEC detects a fault during an automatic start, is any crew intervention required?
No. The FADEC will discontinue the start, clear the engine and attempt a restart (if warranted) automatically
When does the FADEC command a higher engine idle speed?
Bleed Demands
Approach config
High engine or IDG temps
What determines the maximum thrust the A/THR system will be able to command?
The position detent of the thrust lever
What controls the engine LP fuel valves?
Engine MASTER switch
Engine FIRE pushbutton
What does a fault light on the ENG panel indicate?
Auto start abort
Switch disagreement between the HP valve and its commanded position
