Week 3 Part 2

Question 1

What engine is used on the G650?

Answer 1

BR725

Question 2

How many compressor stages does the BR725 have?

Answer 2

10

Question 3

How many turbine stages does the BR725 have?

Answer 3

• 2 stage HP

- 3 stage LP

Question 4

What is P0 air?

Answer 4

Ambient from around EEC in the cowling

Question 5

Hi do you latch and unlatch cowls?

Answer 5

• Latch in to our

- unlatch out to in

Question 6

Above what wind speed should you not open cowls?

Answer 6

13 knots or 15 mph

Question 7

I’m EEC harnesses, what channel is what colour?

Answer 7

• A - yellow

- B - green

Question 8

The fuel drains tank can take fuel from how many normal starts, and how many aborted starts?

Answer 8

• 3 normal starts

- 2 aborted

Question 9

When is rotor bow an issue?

Answer 9

20 mins to 5 hours after engine shutdown

Question 10

What does the EEC do to negate rotor bow if the engine is started 20 mins - 5 hours after it was last operated?

Answer 10

• engine start protect CAS

- engine cranks the engine for longer for cooling prior to ignition

Question 11

The EEC data entry plug stays with the ________

Answer 11

Aircraft

Question 12

The EEC is powered by the ___ bus until N2 is __% when the PMA takes over

Answer 12

• ESS

- 35%

Question 13

Standby engine information/control on the MCDU’s gets signal straight from where?

Answer 13

Channel A of each EEC

Question 14

How many N1 speed probes are there per engine?

Answer 14

• 3
• one for channels A and B
• one spare as not LRU

Question 15

Are the N2 probes LRU’s?

Answer 15

Yes

Question 16

If the APU door failed to close, what might be the issue?

Answer 16

APU door actuator failed

Question 17

What must the APU be prior to working on it?

Answer 17

• shut down

- cooled

Question 18

How many cowl latches need to be closed for an engine run?

Answer 18

All 5

Question 19

Engine TGT must be below ___ degrees for a normal start. ___ motor the engine to cool it of over this limit

Answer 19

• 150

- dry

Question 20

What does green IGN mean on engine start page?

Answer 20

Ignition system is active

Question 21

When using master crank (alternate engine start), what do we lose?

Answer 21

Protections

Question 22

Engine starter limitation is what?

Answer 22

• 3 x 3 minute attempts and then wait 15 mins

Question 23

What component controls the buffer air valves?

Answer 23

Mechanical linkage from the VSV actuator, which is controlled by the EHSV in the FMU

Question 24

What component controls VSV position?

Answer 24

The VSV actuator, which is controlled by the EHSV in the FMU

Question 25

What do VSV’s prevent?

Answer 25

Compressor surge during rapid throttle movements

Question 26

What is soft reversion?

Answer 26

N1 control when the EEC loses a parameter to calculate EPR (AMBER CAS)

Question 27

What is hard reversion?

Answer 27

N1 control hard selected on the SMC (BLUE CAS)

Question 28

How many engine TGT thermocouples are there?

Answer 28

7

Question 29

What are the engine hot red CAS messages? (3)

Answer 29

- Turbine oil fire (550 deg) - hydraulic fluid (135 deg) - FADEC hot (150 deg)

Question 30

Is EVM part of the FADEC system?

Answer 30

No

Question 31

Minimum oil pressure during engine runs is what?

Answer 31

25psi

Question 32

Minimum oil temp for engine start is what?

Answer 32

-40 deg

Question 33

Once you’ve operated the piggy back levers for TR deployment, how long do you have to operate the maintenance test enable switch?

Answer 33

30 seconds

Question 34

On the TR lockout bolts, what must you inspect

Answer 34

Bolt o rings

Question 35

Engine oils can be serviced when?

Answer 35

5 mins to 24 hours after runs

Question 36

Engine oil filter bypasses at __psid and indicates impending bypass at __psid

Answer 36

- 50 | - 28

Question 37

In alternate mode, the engine EEC does not limit ___ on ground

Answer 37

TGT

Question 38

When installing a new igniter and you’ve lost the old washer, what must you carry out?

Answer 38

Immersion depth

Question 39

When do you get an oil filter CAS message?

Answer 39

Impending bypass (28psi)

Question 40

What bus to the igniters use?

Answer 40

- Essential DC - 28V DC in - 3000V out

Question 41

What do the buffer air valves do?

Answer 41

- Allow HP4 air to the bearings | - controlled via VSV actuator

Question 42

What ports fuel from the FMU to VSV actuator?

Answer 42

EHSV in the FMU

Question 43

How do you reset the oil filter DPI?

Answer 43

Remove filter and filter cover and turn upside down

Question 44

With the starter air valve replacement, what do you need to ensure?

Answer 44

V band clamps 90 degrees offset