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Flashcards in Engines Deck (44)
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1
Q

What type of engines does the 737NG have? Rated thrust?

A

2x CFM56-7 engines.

27,300 pounds depending.

2
Q

What is the N1 rotor consisted of?

A

Fan, low pressure compressor and low pressure turbine.

3
Q

What is the N2 rotor consisted of?

A

High pressure compressor and high pressure turbine. All engine gearboxes are powered off the N2 rotor including accessory gearbox and a bleed air starter drives the N2 rotor for engine start.

4
Q

How many ignitor plugs per engine?

A

2 congrolled through the IGN switch.

5
Q

T/F: The dual channel EECs ensure reliablity through automatic transfer in the event of a _______.

A

single channel failure.

6
Q

What are the two modes for the EECs?

A

Normal or Alternate (alternate has hard and soft mode).

7
Q

T/F: Max thrust is always available at the forward stop

A

true.

8
Q

____ and ____ overspeed protection is provided by the EECs in both normal and alternate mode.

A

N1; N2

9
Q

T/F: The EECs provide EGT exceedance protection in normal.

A

False.

10
Q

How do you get to alternate mode in the EEC?

A

EEC automatically goes to soft alternate when signals for normal are lost. This will be indicated by both the ON and ALTN lights in EEC switch.

11
Q

Going from Normal to Soft Alternate shouldn’t have any immediate effect on engine thrust since this mode does what?

A

uses last valid flight conditions to control parameters.

12
Q

How do you get to Hard Alternate for the EECs?

A

retarding thrust levers to idle or manually selecting ALTN via EEC switch.

13
Q

For a given thrust lever position, Hard alternate will _______.

A

Always provide thrust equal to or greater than that provided in Normal.

14
Q

What is the difference between ground min idle and flight min idle?

A

ground: selected during taxi out and after touchdown
flight: selected in flight unless approach idle is active.

15
Q

How is approach idle selected?

A

flaps are in landing configuration or anytime engine anti-ice is selected ON for either engine. Approach idle allows for better engine acceleration in event of go around.

16
Q

An AC power source is generally preferred but the engine can be started using ______only

A

battery

17
Q

What are the power sources for IGN L and IGN R?

A

IGN L: associated AC XFR BUS

IGN R: AC STBY BUS.

18
Q

Which ignition must be used for a battery start?

A

IGN R

19
Q

How do the EECs provide auto-relight capability?

A

In event of flameout both ignites are activated automatically when N2 RPM is below idle or a rapid uncommanded decrease in N2 RPM occurs.

20
Q

What does a magenta X-BLD mean?

A

ambient flight conditions require a crossbled start.

21
Q

______and _______ engine starts are available in flight however the abnormal start protections _________.

A

Windmill; crossbled; are not available.

22
Q

The _____ meters fuel through the ______ to control required engine thrust.

A

EEC; HMU (hydro-mechanical Unit)

23
Q

How many engine fuel pumps are there?

A

2; 1st stage is after spar fuel shutoff valve; 2nd is after fuel filter and goes to HMU.

24
Q

SPAR VALVE CLOSED and ENG VALVE CLOSED (blue ) indicate what?

A

position of the valves.

25
Q

Where is the fuel flow readings taken from?

A

just after the Engine Shutoff valve

26
Q

Oil from the engine driven oil pump is used for what?

A

lubricate the engine bearings and accessory gearbox.

27
Q

When does LOW OIL PRESSURE display?

A

oil pressure is at or below red line.

28
Q

Reverser operation will be at a _________ and some thrust asymmetry can be expected when using standby hydraulic pressure.

A

slower rate.

29
Q

The reverse thrust levers are mechanically restricted from operating until at _______.

A

IDLE. Also, reverse thrust can only be deployed when either RA is reading below 10’ or ground mode is sensed through Air and Ground safety sensor.

30
Q

Movement of either reverser sleeve from the stowed position will illuminate an _________ indication.

A

amber REV.

31
Q

The green REV displays when?

A

once the reverser has reached the deployed position and the reverse thrust lever can no go to the second detent.

32
Q

If you get a MC light and the REVERSER amber light is on what has happened?

A

The reverser light has stayed on for more than 12 seconds. A mulfunction exists.

33
Q

Once a reverser is stowed, motion is inhibited by an ________ lock and a ________ operated locking actuator until extension is selected.

A

electro-mechanical lock; hydraulically

34
Q

Which engine indications are considered primary?

A

N1 & EGT

35
Q

The N1 redline always indicates the N1% RPM ?

A

operating limit

36
Q

After shutdown, a red box around a digital readout indicates what?

A

Inflight exceedance has occured.

37
Q

With AUTO selected, ref N1 readouts are replaced with ______ should the FMC source info become invalid.

A

dashes

38
Q

Where are thrust mode display annunciations shown?

A

Next to TAT on the Primary Eng DU

39
Q

When does Autothrottle limit indication show up?

A

FMC is not providing the AT system with N1 limit values. AT are essentially using degraded N1 thrust limit by EEC.

40
Q

Where is stabilized idle for start?

A

approx. 59% N2.

41
Q

How is max continuous EGT line displayed?

A

amber line at EGT

42
Q

A white flashing box of the EGT means what?

A

impending hot start or compressor stall.

43
Q

What does an amber ENG FAIL light mean on the EGT gauge?

A

Start lever is in IDLE and engine is operating below 50% N2. It remains until the engine recovers, the FIRE switch is pulled or the start lever is moved to CUTOFF.

44
Q

Fuel flow readouts can be adjusted to show?

A

Present FF or F used.