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Flashcards in 6 - Engine Deck (39)
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1
Q

What type of engines does the CRJ have?

A

General electric CF34-3B1 HOT AND HIGH

2
Q

What is the normal takeoff thrust rating?

A

8729 pounds per engine

3
Q

How much thrust is produced when the APR is activated?

A

9220 pounds, which is a 2% increase

4
Q

Explain the general make up of the N1 and N2 sections of the engine.

A

The N1 section is a single stage fan connected to a four stage low pressure turbine by A shaft. The N2 sec. is a 14 stage axial flow Compressor connected to a two-stage high pressure turbine by a shaft.

5
Q

What section of the engine drives the accessory gearbox?

A

The N2 Compressor

6
Q

The bypass N1 airflow on take off produces how much of the thrust?

A

80%

7
Q

Do the thrust reverses direct core or bypass airflow forward to assist in breaking?

A

The bypass airflow is diverted forward

8
Q

What improves efficiency of the N2 compressor and protects against stall and surge damage?

A

A variable geometry Compressor (VG). The VG change is the angle of attack of the inlet guide veins and the first five stages of the Stater Vanes. The changing of the angle of attack optimizes the airflow for best efficiency. The fuel control unit (FCU) uses fuel to hydraulically change the angle of the vanes.

9
Q

Where is the ITT measured? And what does it stand for?

A

Inter Turbine Tempurate it is measured between the high and low pressure turbine.

10
Q

What equipment does the accessory gearbox drive?

A
Alternator, which powers the N1 control amplifier.
Lubrication pumps for the engine.
Hydraulic pump.
Fuel control unit and engine fuel pump.
Integral drive generator (IDG)
11
Q

What are the different jobs of the fuel system?

A

Provide motive flow to the main ejector pumps and scavenge pumps.
Lubricate and actuate servos in the FCU.
Cool engine oil.
Adjust the variable geometry compressor linkage.

12
Q

what are the different ways to stop fuel flow to the engine?

A

Shut off the thrust lever.

Press the fire switch light on the glareshield panel.

13
Q

What is the purpose of the fuel oil heat exchanger?

A

The exchanger warms the fuel and cools the engine oil

14
Q

Are any of the fuel filters displayed on the fuel synoptic page?

A

Yes, one for each engine.

15
Q

How would you know the fuel temperature at the fuel filter?

A

The temperature is displayed next to the fuel filter on the fuel synoptic page.

16
Q

What occurs when a fuel filter is clogged?

A

The fuel will bypass the filter. There will be an EICAS caution message along with an amber fuel filter on the fuel synoptic page.

17
Q

What controls the VG inlet guide vanes and Stater vanes of the engine compressor?

A

The fuel control unit

18
Q

Explain N2 speed control.

A

During low power settings up to 79% N1, the FCU hydro mechanically Controls the N2 speed of the engine. This is so that matched movement of the thrust levers produces fairly matched N2 RPM.

19
Q

Explain N1 speed control

A

Above 79% N1 the N1 Control amplifier controls engine RPM. The engine speed switches have to be on for this to occur. This is so that matched movement of the thrust levers produces fairly matched N1 RPM.

20
Q

What would happen at a cruise flight if the engine speed switches were turned off?

A

There would be an increase in RPM and ITT that could exceed limitations.

21
Q

How would you know if there were an impending oil filter bypass?

A

There would be no EICAS indications. In the AFT equipment bay there are associated indications

22
Q

How would you know if a chip detector had detected some metal in the engine oil?

A

There would be no EICAS indications. In the after equipment bay there are associated indications.

23
Q

How can the engine oil be checked and replenished?

A

Located on the Captains side panel is the engine oil level Control Panel. This level can be tested and filled from this panel.

24
Q

Explain the engine oil test.

A

Press the start stop switch light for the oil test. If an engine is low, the refill, lights will illuminate. The white stop light will illuminate after the test if both engine oil levels are normal.

25
Q

What does the amber FAIL light in the engine oil level LH or RH switch light indicator?

A

This will illuminate during and Engine oil level check to indicate a failure of an oil level sensor

26
Q

What type of engine starter does the CRJ have?

A

An air turbine starter

27
Q

What two things are required to open the starter valve and engage the starter?

A

DC Power

10th stage bleed air

28
Q

What does the air turbine starter actually drive?

A

It drives a gearbox that drives the N2 section

29
Q

At what N2 speed does the start valve close automatically?

A

55% N2

30
Q

If just the engine starter was activated and no fuel added, what maximum N2% would the starter achieve?

A

30%

31
Q

What are the two ways the start valve will close?

A

Press the stop switch light on the start ignition panel

When the N2 RPM is above 55%

32
Q

What valves Open when the engine START switch light is pressed?

A

L and R 10th stage bleed SOVs.
10th stage ISOL valve
Start valve for the engine that is being started

33
Q

Are the ignition systems DC or AC powered?

A

Ignititon A and B are AC ignition Systems. Ignition system B has a static inverter that turns DC in to AC power

34
Q

What are the power sources for ignition a and B?

A

The AC Essential bus powers ignition a
The battery bus powers ignition B through a static inverter. This is why ignition B is used when only DC power is available for start.

35
Q

Does continuous ignition activate ignition A or B?

A

Both are energized.

36
Q

What does pressing the TOGA switch do while on the ground in addition to controlling the FD Bars?

A

Updates the FMS position

37
Q

Explain the thrust reverser emergency stow?

A

If the thrust reverser unlocks in flight the pilot should press the affected emergency stow switch light on the panel. This will direct 14th stage bleed air to the PDU and stow the reverser.

38
Q

How long is the automatic performance reserve system (APR) armed after take off?

A

The APR is armed for five minutes after takeoff. The APR arms when N1 RPM is above 79%

39
Q

When will the APR activate?

A

When an engine N1 decreases to 67.6% and the APR is armed, the APR will activate. The APR sends the signal to both engines to increase N1 by 2%.