Engines, APU Flashcards
Which system regulates the engine?
A dual channel Electronic Engine Control (EEC) regulates each engine. The EEC monitors auto-throttle and Flight Crew inputs to automatically set engine thrust.
What is the indication an EEC is operating in normal mode?
In normal mode, white ON lights are the only lights illuminated on the associated EEC switch on the engine panel.
What are the indications of EEC hard and soft alternate modes?
- EEC Hard Mode is indicated by the illumination of only ALTN.
- EEC Soft Mode is indicated by the illumination of both ON and ALTN, assuming that the thrust lever has not been retarded to idle.
The EEC’s provide redline overspeed protections for which engine parameters?
The EEC’s provide N1 and N2 redline overspeed protection in both normal and alternate modes.
When do the ECC’s select approach idle for the operating engine?
Approach idle improves engine acceleration time in the event of a go-around.
It’s selected:
*with Flaps 15 or greater, or
*any time the flaps are not fully retracted and engine anti-ice is on
Approach idle is maintained until after touchdown, when ground minimum idle is selected.
What does the ENGINE CONTROL amber light indicate and when is it armed?
- A detection of a fault in the Engine Control System which is not dispatchable.
- The light operates when:
o The respective engine is operating, and
o the aircraft is on the ground, and
o below 80 knots prior to takeoff, or 30 seconds after touchdown.
When is the ENG FAIL (amber) alert displayed?
- The ENG FAIL is displayed on the EGT indicator when the engine is below sustainable idle (62% MAX, 50% NG) with the Start Lever in the IDLE position.
- The alert remains until:
o The engine recovers.
o The engine start lever is
moved to CUTOFF, or
o the fire switch is
pulled.
How are the secondary engine alerts toggled?
- Push the “SYS” button.
- The secondary engine alerts will appear automatically when:
o The displays are initially powered.
o A secondary engine parameter exceedance occurs.
o in flight and an engine start lever is moved to CUTOFF.
o in flight and N2 is below idle RPM (ENG FAIL).
How are EGT redline exceedances indicated?
The digital readout, box, needle and indicator change color to red or amber.
How is an EGT exceedance displayed after engine shutdown?
After engine shutdown on the ground, a box the color of the exceedance (red or amber) will be displayed around the digital readout indicating that an in-flight exceedance has occurred.
How is the N1/SPD REF SET page displayed on the Max Display System?
By selecting INFO on the MFD panel on the forward electronic panel.
What does the THRUST crew alert on the Engine Display indicate?
- indicates the associated engine thrust is more or less than the commanded thrust.
- The N1 command sector (arc indicating the difference between commanded and actual thrust) will fill in amber when there is a difference between commanded and actual thrust.
What are the indications of reverse thrust on the Engine Display?
- REV in amber indicates that the reverser is moving from or to its stowed position (note: the Systems Handbook only states that it displays in amber when it is moving FROM its stowed position).
- REV in green indicates that the reverser has reached its deployed position and the reverse lever can be raised to detent number 2.
What does selecting FUEL USED display?
Selecting USED will display fuel used since the last reset for 10 seconds, then automatically revert to fuel flow.
What does the illumination of the FUEL FLOW crew alert indicate?
Illumination of FUEL FLOW indicates that fuel flow is abnormally high when compared to the FMC expected fuel flow.
What does the illumination of the OIL FILTER BYPASS light indicate?
Appears when there is an impending bypass of the Oil supply Filter.
Which engine start ignitor is available on standby power?
The right igniter plug receives power from the AC standby bus.
(The left igniter plug receives power from the associated AC transfer bus)
The auto-relight function of the Engine Start System is available when the engine start switches are in which position(s)?
Any position.
Which start malfunctions do the EECs monitor for during engine start?
- Hot starts,
- Engine Stalls,
- EGT start limit exceedances,
- Wet Starts.
*These protection features do not function during in-flight starts.
How is an impending hot start indicated during engine starting?
If an impending:
*hot start is detected by a rapid rise in EGT or EGT approaching the start limit
or a
*compressor stall occurs, the white box surrounding the EGT digital readout flashes white.
What does the illumination of the REVERSER LIMITED light indicate?
- In flight:
- A fault in the thrust reverser system limits
reverser thrust. - The thrust reverser will not deploy or
reverse thrust will be limited to idle if
commanded.
- A fault in the thrust reverser system limits
- On the ground:
- A malfunction has occurred.
What does the illumination of the REVERSER COMMAND light indicate?
The reverse thrust lever is not in the down position in flight.
Does the APU require the BAT switch to be on to operate?
yes.
How long should the APU run after illumination of the APU GEN OFF BUS (blue) light before opening the APU bleed valve?
A full 2 minutes.
How long should a pilot wait after the APU switch is selected OFF before selecting the BAT switch OFF?
3 minutes for the MAX,
2 minutes for the NG.
What will cause the automatic shutdown of the APU?
- RPM overspeed
conditions. - Low oil pressure.
- High oil temperature.
- APU fire.
- Fuel Control Unit failure.
- EGT exceedance, and
- other system faults
monitored by the ECU.
