DQ-135

Question 1

Explain the three types of engine limiting and which components are responsible for controlling them.

Answer 1

TGT Limiting - DEC/EDECU: 866*C (10 min) or 891*C (contingency 2.5 min) - prevents destructive TGT limits. (HMU can also limit fuel flow when T4.5 reaches a spesific limit - lower than DEC limiting)

NG Governing: HMU mechanically computes and sets MAX NG speed iaw T2 sensor (Max 103% Ng. Less Ng allowed in extreem cold. Mechanically (flywheel) shutdown @ 110% NG)

MAX Fuel Flow: Physical limit - “pipe” (meter valve) full open. Ie. not limited by either PAS, LDS (via HMU), or DEC (TGT) via torque motor.

Question 2

Explain what occurs during an engine high side failure to both the functioning and malfunctioning engine.

Answer 2

The good engine will only attemt to increase torque upward until Np is 3% above the reference Np (cockpit set reference)

High-side engine will increase RPM (1 or 2) and also RPM R. If TGT limiting (DEC) does not work, engine will “flameout” when Np reaches 120 (+- 1)% and re-ignite once back under 120% Np.

Question 3

Increasing the collective with an engine power controllever in lockout will, will not, or may require advancing the PCL?

Answer 3

It depends…
Increasing the collective with an engine power control-lever in lockout may require advancing the PCL (will normally stay close to 10% setting below good engine if set correctly initially - 10% blw good engine @ cruise condition.
If it is set 10% lower than good engine at low(er) power demand, it may require a reduction as TRQ loading is increased.

Question 4

During engine start the PCL is advanced to idle, no rise in TGT occurs, explain possible reasons why.

Answer 4

Lack of Ignition or Fuel:

• Eng ignition switch OFF
• Fuel system selector in OFF
• Frozen fuel line

Question 5

Explain the indications and what would occur if the collective bias tube pin were to shear.

Answer 5

Internal spring will attemt to reset LDS to a position equal to full up collective (fault to high demand).

Np governing will shutoff fuel @ 120 % with DEC/EDECU working propably.

If failure occurs at IDLE, Ng speed (affected engine) will indicate higher than normal (Ng 63% within 3%).

Question 6

Given the following cruise conditions what is the Maximum Rate of Climb IAS/ Torque and explain how is it calculated?

TEMP 40 Degrees
PA 2000’
ACFT GWT 20000 LBS
ETF 1.0/.92

Answer 6

Maximum Rate of Climb IAS/ Torque:
Max End. Spd. corrected for ATF -> Max TRQ (7A-47)
Check D btw Max Avail. TRQ @ End. Spd. & End. TRQ
Check for climb-rate abv/blw 1400´/min
Asp. correction - add 12 kts

Max RC IAS: 79 + 12 kts = 91 KIAS
Max RC TRQ: 124% - NO 10 Min. limit effecting Max TRQ - extreem cold temp

TEMP 40 Degrees
PA 2000’
ACFT GWT 20000 LBS
ETF 1.0/.92

Question 7

A PC berating a PI for incorrectly programming the GPS and getting lost is a failure of which crew coordination objective?

Answer 7

Failure of which crew coordination objective:
Establishing Team Relationship