Engines and APU Flashcards
What happens when GND is selected?
- The start valve opens to supply air to the starter
- the selected igniters are armed
How long is the GND position magnetically held for?
Until N2 reaches 50% RPM. The start valve closes and ignition terminates
With the engine start selector in auto position when are selected igniters in constant operation?
-Extending slats -turning engine anti-ice on
What is the difference between the CONT and FLT position for switch?
CONT- operates selected igniters continously with no time limit and signals engines to operate at a minimum of approach idle speed.
- FLT - Operates both igniters cont regardless of the igntion selector position, no time limit.
With Fuel control Valve in Run position, what does that mean?
Eng and Spar Valve are opened. Selected ignitors are turned on.
When must CONT be selected for ignitors?
In severe turbulance
Can you use the TMSP to remove the flex/assumed temp takeoff selection?
Yes, selecting TO/GA will revert to normal TO thrust
Does an EEC have over temp protection?
NO
What is the EEC powered by?
Each EEC is powered by its dedicated generator independent of the airplane electrical system and operates anytime the engine is running.
EEC switches changed to ALTN instead of normal means?
It is now powered by the hot battery bus
If the EEC or the EEC gen fails what happens?
The engine shuts down
What does the OIL PRESS ind light mean?
- L or R ENG OIL PRESS is at or below minimum.
- There is an oil pressure switch malfunction
What are the Oil quantity minimums ?
- recommended 17 qts min for start.
- if its less than 17 before start, verify that a min of 8 quarts is displayed after engine warm up and at an idle thrust setting. (if less than 8, dispatcher approval is required to continue)
What happens when reverser is set to interlock position?
- Autothrottle disengages
- Auto speedbrakes deploy
- Reversor Isol valve opens
- Blocker doors rotate into place
- REV appears in amber above each EPR
- REv changes to green when fully deployed
When TAI displayed in green on the EICAS display vs amber what does that mean?
Green means eng anti-ice is on, amber means its on but n1 is too low.
When do you turn fuel control switch to run?
at 25% n2 or maximum motoring speed, whichever occurs first, not less than 18% n2. (18% is represented by the dash line)
When should engine start be aborted?
- oil pressure does not rise
- fuel flow is abnormally hihg or fluctuating
- egt fails to rise with 20 seconds of selecting run
- egt rises too rapidly or approaches the limit
- n1 fails to increase after egt rise
- egt quickly nears or esceeds the start limit
- the oil pressure indicatinos are not normal by the time the engine is stabilized at idle
What is the starter Duty cycle?
5 min, 30 sec off (2 times) then 5 min , 10 min off.
What is the minimum required warm up time?
3 min but target is 5 min. (can TO if 3 min is achieved)
What is the required cool down time?
3 min or gate arrival
-300 What is the difference between NORM (EPR) Mode, vs. ALTN (N1) mode,.
NORM - EEC provides over boost and over speed protection for the engine.
ALTN- the EEC provides over speed protection only.
-300 What is the minimum N2 to add fuel?
15%
What altitude can you operate the aircrafts APU up to and provide electrical power?
Service ceiling
To what altitude is APU bleed air available?
17,000ft
Which tank does the APU receive fuel from?
Left Main tank
Is everything normal if a fault momentarily illuminates during APU start?
Yes, fault will temperarilly show when valve is in transit
What is the APU starter duty cycle?
3 attempts in 60 min
What does the illumination of the FAULT light indicate?
- APU has automatically shut down
- APU has shut down as a result of an APU fire
- APU fuel valve, disagrees with the commanded position
