Engines And APU Flashcards
When are secondary engine indications displayed?
Displays initially receive PWR
In FLT when eng start lever is moved to cutoff
In FLT when N2 RPM is Below idle
A secondary eng parameter is exceeded
Till when are secondary eng indications displayed
Till condition is no longer present
What happens to indications when EEC is not powered?
It comes directly from the eng sensors
When does EEC receive PWR
When ENG start switch is moved to GRD and N2 greater than 15%
When does EEC alternatief between channels?
With each eng start attempt and when operating channel fails
What is used by EEC to set thrust?
N1
What happens with loss of either DEU?
EEC’s revert to ALTN mode to prevent engines operating on a Single source of data
What is the threat in hard ALTN mode?
Thrust protection not provided and max rated thrust reached at TL less than Full forward
When does filter bypass light illuminate?
In case of impending bypass of filter
Where is FF measured
After Engine fuel shutoff valve
What does GRD do?
It uses BAT PWR to close ENG bleed air valve and open the start valve.
On GND arms selected igniter
In FLT arms both igniters
Why can EGT rise earlier than FF?
Because FF indications lag by 2 secs
For what kind of abmormal starts do the EEC’s provide protection?
Hot start, eng stall, wet start and EGT start limit exceedance
From which buses do Left and right igniters receive Power respectively
Left: AC TRX BUS 1
Right: AC STBY BUS
When does auto-relight occur?
In case of uncommanded Rapid decrease in N2 or N2 is below idle RPM
What happens to reverser light on aft OVHD panel?
After reverser is Commanded to stow, It illuminates untill isolation valve closes. (Takes normally 10 seconds) If It is illuminated for 12 secs master caution light illuminates
What happens in case of incomplete stowage of thrust rev?
Auto-restow circuit stows reversers
What elec PWR does the APU need to start?
AC TRX BUS 1 or main BAT
What is normal EGT for APU start
1100 degrees
When does APU shutdown occur?
60 sec’s After APU switch off
What is amber N1?
N1 value for full rated thrust
What does amber rev light indicate
Reverser moved from stowed Pos
When is oil filter Bypass alert blinking inhibited?
80 knots to 400ft RA
200FT RA to 30 sec’s After ldg
What is meant by amber on secondary eng indications?
Caution range
