Engines, APU Flashcards
What is the required engine warm up period prior to applying T/O power?
Minimum of 3 minutes. Target is 5 minute warmup, but don’t delay takeoff if 3 minute warmup has been attained.
What six conditions would lead to aborting an engine start?
-Oil pressure rise does not occur
-Fuel flow abnormally high or fluctuating
-EGT rising too rapidly or approaching limit, or if EGT fails to rise within
20sec of selecting RUN
-N1 fails to increase after EGT rise
-EGT quickly nears or exceeds the start limit
-The oil pressure indication is not normal by the time the engine is
stabilized at idle
What is the required engine cool down time prior to engine shutdown?
3 minutes or gate arrival, whichever is less.
When should the fuel control switch be placed to RUN during an engine start?
- verify N2 rotation and that the oil pressure increases
- when N2 is at 25%, or if 25% is not possible, at max motoring and a minimum of 18% in the 757, 15% in the 767.
A magenta bug (fuel on command bug) appears at what N2 speed?
18% in the 757
15% in the 767
What’s the APU starter duty cycle?
3 start attempts in 60 minutes
Max altitude to use APU electrics?
Aircraft service ceiling
Max altitude to use APU pneumatics?
Approximately 17,000ft
What do EEC’s provide?
Over boost and overspeed protection, but no over temp protection
What’s the primary indication for setting thrust on PW engines?
EPR
What’s the primary indication for setting thrust on GE engines?
N1
How can you cancel an APU shutdown if the APU has been selected OFF and the RUN light is still illuminated?
Momentarily move the APU selector to the start position.
What does an illuminated APU RUN light signify?
APU is at operating speed
What does an amber illuminated APU FAULT light indicate?
-the APU has automatically shut down
-the APU fuel valve disagrees with the commanded position
-the APU will auto shutdown for an APU Fire
NOTE: the FAULT light momentarily illuminates during APU start when the fuel valve is in transit.
What is the engine starter duty cycle?
- 5 minutes continuous
- cool 30 sec per minute of starter operation
- after 2 consecutive 5 minute cycles, cool the starter for 10 minutes prior to each subsequent starter duty cycle
What does an illuminated L or R ENG OIL PRESS light mean?
- respective oil pressure is at or below minimum
- oil pressure switch malfunction
What are the oil quantity requirements?
- 17qts recommended for start
- if quantity is less than 17, verify 8qts at idle following engine warmup
- if less than 8 quarts following engine warmup, dispatcher approval required.
How do you manually select a desired thrust reference mode?
Push the controls on the Thrust Mode Select Panel (TMSP)
How can you verify the selected TMSP mode is active?
It will be displayed above the primary thrust reference (N1 or EPR as appropriate)
What does the TEMP SEL knob on the TMSP do?
Rotates to select assumed temperature in lieu of using the FMS to enter an assumed temperature.
If assumed temperature has been entered and normal thrust (takeoff power) is desired, how can this change be made with the TMSP?
Selecting TO/GA on the TMSP will eliminate the assumed temperature and select normal thrust (takeoff power).
On the upper EICAS display, what does a TAI indication signify?
Thermal Anti-Ice
- green- engine anti-ice is on
- amber- engine anti-ice is on, but N1 too low
Where is the EICAS TAT (total air temperature) displayed?
Upper EICAS. On the ground, TAT approximates OAT.
How are engine exceedances displayed on the EICAS?
Current exceedances are displayed in red.
Max exceedances are displayed in white below the indicator.
Engine start selectors: what does the GND mode do?
Push in and rotate-
Opens start valve to supply starter air
Arms selected igniter(s)
Selector magnetically held in GND position until 50% N2 RPM.
Engine start selectors: how does AUTO mode work?
-Selector releases to auto at 50% N2 RPM
-Closes start valve and terminates ignition
-Selected igniter(s) operate continuously with LE slats extended or
engine anti-ice on.
Engine start selectors: what does OFF mode do?
Provides no ignition.
Engine start selectors: what does CONT mode do?
- selected igniter(s) operate continuously
- no time limit
Engine start selectors: what does FLT mode do?
- both igniters operate continuously regardless of ignition selector position
- no time limit
What is the function of the engine fuel control switches?
RUN - normal position for engine operation
- opens engine and spar fuel valves
- activates selected igniter(s)
CUT OFF- closes engine and spar fuel valves
- terminates ignition
What are the indications for the thrust reverser system?
REV(amber)- the reverser is in transit
REV(green)- the reverser is fully deployed
