ORAL *E145 APU Flashcards
Does APU have a FADEC?
Yes
What causes APU Shut down on ground
HOTLOP…Failure to start, accelerate, or light. Loss of RPM data, external short, loss of FADEC signal or failure, loss of EGT. FIRE, Overtemp, overspeed
APU Fire shuts it down on ground in how long?
10 seconds
APU auto shutdown in flight?
over speed, over temp Failure to start, light, or accelerate, Loss of RPM data short FADEC failure or loss of signal
Loss of which buses would cause APU shutdown?
HOT BUS 1…immediate
ESS DC 2…6 seconds
Which tank does APU draw fuel from
Right
Can left tank supply APU fuel?
Yes, with Crossfeed valve
APU OIL HI TEMP?
166C
What does ON Position do?
Energizes FADEC, Opens fuel shutoff valve, and enables APU indications on EICAS
What does OFF position do (APU)
De energizes FADEC, Closes fuel shutoff valve. Removes APU from EICAS if less than 5 % RPM, and commands shut down
FADEC ignition? And open Main Fuel valve?
3% RPM on ground, 0% RPM in flight
APU Starter cutout
50%
APU Ignition Cutout
70%
Power and Bleed available?
95%
Normal APU Shutdown
STOP button, from a loaded condition
APU Overspeed
104% Auto shutdown
What does Stop button do.
Commands a stop request and closes fuel shutoff valve
APU Fuel Shutoff?
Closes APU fuel shutoff valve
WHY USE APU STOP?
EICAS messages remain
Max Alt APU start
30k
Max Operating altitude APU?
37k
Max EGT during APU start
884C
APU Max EGT continuous
680C
EGT Exceedence limit?
717C for 5 minutes
Minimum Battery temp for APU start
-20C
Minimum temp for APU start with external power
-54C
APU Starter Limits
3 attempts…1 minute cool down.
Must wait 30 minutes for 3 more attempts
Start….
Turn to on, wait 3 seconds, then turn to STArt
Normal Shutdown, When do you turn knob to off
After less than 5% RPM
AHRS consideration
Wait 30 seconds for AHRS config before starting APU
