Engine Flashcards
When with the EEC abort a start in autostart?
- Hot Start
- Hung Start
- No EGT rise
- Compressor stall
- Start shaft failure
- No N1 rotation
- Insufficient air pressure for starter operation
- Start time exceeds the starter duty cycle timer.
When is continuous ignition automatically provided?
Flap lever is out of the UP position
Engine anti-ice is on
When is continuous ignition inhibited?
On the ground when N1 is 60% or less.
When can you use reverse thrust?
Only when the forward thrust levers are in the idle position and on the ground with the engine running.
What are the EEC idle selections?
Minimum idle or approach idle. Minimum idle is a lower thrust.
When is approach idle selected?
- Engine anti-ice is operating
- Flaps are commanded to 25 or greater
- 1 hydraulic system air-driven demand pump is inop and the flaps are out of the UP position
- The opposite engine bleed air valve is closed.
Describe Approach Idle
It decreases acceleration time for a go around.
Maintained until after touchdown.
What are the different EEC modes?
Normal, Soft Alternate, and Hard Alternate
What protections do you have in Normal EEC Mode?
Thrust reference, Thrust limit protection, and Overspeed protection
When will the TAC (Thrust Asymmetry Compensator) automatically disengage?
When reverse thrust is applied Due to system malfunction When engine thrust data is lost When the flight controls leave the NORMAL mode and go to either secondary or direct If the engine is damaged or surges
When the PFC (Primary Flight Control) switch is in auto and there are no other malfunctions, what flight control mode are we in?
Normal
How do the flight controls revert to the secondary mode?
Automatically, as a result of internal faults or failures
How many fire detection/overheat loops does each engine have?
2
What causes a fire or overheat warning?
Detection of the condition by both loops is required unless one loop has failed.
What happens when you pull an engine fire switch?
- Shuts off fuel, air, electrical, and hydraulic
- Depressurizes the hydraulic pump
- Disarms the respective thrust reverser
- Arms both bottles for discharge
What happens if the EECs detect an internal fault?
The automatically go into the soft alternate mode.
What is the backup power source for the EECs?
Aircraft AC power.
What keeps the EECs (electronic engine controls) powered during a double engine failure?
PMG (permant magnetic generators)
Why do we select the hard alternate mode if the EEC has gone into the soft alternate mode?
To prevent thrust lever stagger at even thrust settings or to prevent asymmetrical thrust when thrust levers are not staggered. Also to regain the command and reference promts on the N1 indications and to use a broader date base.
What must we do before selecting the hard alternate mode and why?
Retard the thrust levers to the mid positioin to prevent over boost.
Is autothrottle available in the hard alternate mode?
Yes
How many start attempts will the auto-start system make on the ground and in flight?
3 on the ground, unlimited in flight.
What should you know about thrust lever position and actual thrust between the normal and alternate modes?
The same thrust lever position in the alternate mode yields either equal or greater thrust than the normal mode.
What is the difference between soft and hard alternate with respoect to reference data/
Soft alternate freezes what is happening now and uses it for as long as it is active, hard alternate has a standard program already present for reference.
When will auto-start not attempt another start on the ground?
No N1
Insufficent air pressure
starter shaft failure
starter duty cycle exceeded.
What does auto-start NOT monitor?
Oil temp and pressure
What action should you take for no oil pressure during start?
Fuel control to cut off
Call maintenance
Do NOT motor the engine
When does the TAC(Thrust Asscementry Compensator) turn on?
When N1 values vary by 10% or more.
