Engines/APU

Question 1

What type of engines do we have?

Answer 1

CFM56-7 high bypass, dual rotor, axial flow turbofan engines

Question 2

What does the N1 rotor consist of?

Answer 2

N1 fan
Low pressure compressor (booster)
4 stage low pressure turbine

Question 3

What does the N2 rotor consist of?

Answer 3

9 stage high pressure compressor
High pressure single stage turbine

Question 4

What is main purpose of high pressure turbine?

Answer 4

Turn the high pressure compressor and accessory drive.

Question 5

What items are found in the accessory drive?

Answer 5

Hydraulic pump
Oil scavenge pump
Engine fuel pumps
Integrated drive generator
Starter

Question 6

What are the two modes of the EEC (Electronic Engine Control)?

Answer 6

Normal mode
Alternate mode

Question 7

What are the two alternate modes for the EEC?

Answer 7

Soft mode
Hard mode

Question 8

When the airplane goes into soft alternate mode, what are the indications?

Answer 8

An ALTN light illuminates on the EEC switch and the ON indication remains visible

Question 9

When do the ENGINE CONTROL lights illuminate?

Answer 9

-Ground only
-Indicates that the aircraft is not to takeoff due to engine control system malfunctions
-Below 80 knots prior to take off or
Approx 30 seconds after touchdown

Question 10

What are the 3 different EEC commanded idles?

Answer 10

Ground idle
Flight idle
Approach idle

Question 11

When does the EEC command these idles?

Answer 11

Ground idle for ground ops
Flight idle for most phases of flight
Approach idle if flaps are in landing configuration or engine anti-ice is on for either engine
- if a fault prevents the EEC from receiving flap and anti-ice signals, approach idle schedule begins below 15,000 MSL

Question 12

Engines: REVERSER lights

Answer 12

Normally off, when illuminated:

• normally illuminated For 10 seconds during TR Stow or disagreement ( More than 10 secs call maintenance

Question 13

Engines: Reverser triggers master caution (Eng) for “4” reasons.

Answer 13

Auto restow circuit has been activated

Thrust reverser sleeves not in commanded state (1 or more)

Isolation valve not in commanded position

Sync-lock circuit failure has been detected

Question 14

APU: EEC auto shutdown APU for what reasons?

Answer 14

Over speed
High oil Temp
Low oil press
APU Fire
EGT exceedance
Fuel control unit failure

Question 15

APU: when will the OVER SPEED light illuminate?

Answer 15

1. APU RPM limit has been exceeded resulting in auto shutdown
2. Over speed shutdown protection feature has failed a self test during normal APU shutdown
3. If illuminated when APU switch is placed off, extinguishes 5 mins
4. Light disarmed when APU is off

Question 16

Engines: EEC will auto shutdown engine start on the GROUND only for what conditions?

Answer 16

Hot starts
Engine stalls
EGT start limit exceedances
Wet starts (No EGT rise)