Engines and APU

Question 1

What is the purpose of the Electronic Engine Control (EEC)?

Answer 1

Full Authority Digital Engine Control (FADEC)

Controls forward and reverse thrust

Controls engine idle speed (ground, flight, or approach)

Controls maximum thrust ratings

Protections
-N1/N2 overspeed
-Overboost
-EGT (ground starting only)
-Abnormal start protections (hot, wet, stall)
-Flameout protection (Below idle or sudden drop in N2)

Question 2

What is the color logic of the REV indicator above N1?

Answer 2

Amber REV
–Reverser moves from stowed position (in-transit/disagree)

Green REV
–Reverser reached deployed position

Note: Reverse thrust can be raised beyond detent 1 once deployment reaches 60% (still Amber REV)

Question 3

How do you display fuel used?

Answer 3

Fuel Flow Switch to USED

Question 4

What is indicated by the ENGINE CONTROL (amber) light?

Answer 4

Non-dispatchable engine fault

Inhibited unless engine is operating and aircraft on the ground

Question 5

What light(s) indicate the EECs are in normal mode?

Answer 5

White ON and NO ALTN (amber)

Question 6

Describe EEC Hard vs Soft Alternate

Answer 6

Manually selected or insufficient data inputs to EECs then automatic

Soft Alternate
-Engaged until hard alternate manually selected, or
-Thrust lever retarded to idle

Hard Alternate
-Thrust is always equal to or greater than selected

White ON and amber ALTN – hard or soft alternate

No ON and Amber ALTN – hard alternate

Question 7

What indicates an EGT exceedance after engine shutdown?

Answer 7

Red box around EGT digital readout

Question 8

How is a hot engine start indicated during ground starting?

Answer 8

Flashing white EGT

EEC automatically cuts fuel and ignition for impending hot starts to EGT exceedances

Not applicable in-flight

Question 9

What is flameout protection?

Answer 9

Auto-relight capability (both ignitors activated) for
-Uncommanded rapid decrease in N2, OR
—activates ignition for 30 seconds

-N2 below idle RPM
—activates ignition til 5% N2 airborne, or 50% N2 ground

Start switch can be in ANY position

Question 10

When do the EECs command approach idle?

Answer 10

Engine Anti-Ice selected ON for either engine, or

Flaps in the landing configuration

Question 11

EECs provide redline protection for which parameters

Answer 11

N1 Overspeed
N2 Overspeed
EGT during ground engine starting
Overboost

Other (non-redline protections)
Abnormal ground start protections
Flameout protection

Question 12

What Abnormal Start Protections are provided by the EEC?

Answer 12

-Impending hot starts,
-EGT exceedance,
-Engine stall,
-Wet start (no EGT rise w/in 15 sec of raising Start Lever)

EEC automatically shuts off fuel and ignition

**ground starting only! Does not apply in-flight

Question 13

What causes an ENG FAIL alert?

Answer 13

N2 < 50% and

Start Lever IDLE

Question 14

What does the APU provide?

Answer 14

Bleed air for engine starting and air conditioning

Electrical generator

Start, run, and electrics up to 41,000’
Bleed load only up to 17,000’
Bleed and electrics up to 10,000’

Question 15

What powers the APU Electronic Control Unit (ECU)?

Answer 15

Switched Hot Battery Bus

Battery switch must be ON

**Placing Battery Switch to OFF causes APU shutdown!

Question 16

How long must you wait after APU shut down before placing the Battery Switch to OFF?

Answer 16

NG - 2 minutes

MAX - 3 minutes

Question 17

Will the APU start without battery power?

Answer 17

No, switch hot battery bus powers APU ECU

Battery switch must be ON

Question 18

What will cause an automatic shutdown of the APU?

Answer 18

Fault,
Fire,
Overspeed,
Low oil pressure,
High oil temperature,
EGT exceedance,
Fuel control unit failure,

Or Battery Switch OFF!

Question 19

What indicates a thrust reverser malfunction?

Answer 19

REVERSER light illuminated for > 12 seconds

Master Caution/ENG illuminate

**Normal to see REVERSER light up to 10 seconds; Master Caution/ENG inhibited

Question 20

What causes a REVERSER (amber) light

Answer 20

Illuminates when thrust reverser is commanded to stow

Extinguishes ~10 sec later when isolation valve closes

Malfunction exists if REVERSER illuminated for > 12 seconds
–MASTER CAUTION/ENG then illuminate

Question 21

With the EEC in ALTN (amber), thrust lever not IDLE, what mode is the EEC in?

Answer 21

Not enough information, is ON illuminated or not?

If ON is NOT illuminated then in HARD alternate

If ON is illuminated then in SOFT alternate

Question 22

What system controls maximum thrust ratings?

Answer 22

Electronic Engine Controls (EECs)

Note EECs also provide
-Foward/reverse thrust control
-N2 Idle speed control
-Protections for
–N1/N2 overspeed
–Overboost
–EGT during ground engine starting
–Abnormal start protections
–Flameout protection