PHI GOM S-92A - POWER TRAIN

Question 0

What angle is the main rotor mast tilted?

Answer 0

5° forward tilt.

Question 1

What sub assemblies make up the Main Transmission Assembly?

Answer 1

Main module
2 input modules
2 accessory modules

Question 2

The input modules reduce high-speed shaft RPM from ______ to ______ RPM.

Answer 2

About 22,000 RPM from the HSS to 7,500 RPM input to the maintrasmission.

Question 3

What is the oil capacity of the MGB?

Answer 3

10.5 gallons

Question 4

How is the MGB system oil cooled?

Answer 4

External cooler radiator and blower assembly.

Question 5

Below what temperature will MGB oil bypass the cooler?

Answer 5

55°C

MTM 63-35

Question 6

How many times does the fuzz burn attempt to clear the chip before turining on the CHIP light?

Answer 6

6 pulses.

If the chip is 45 ohms the light will illuminate

Question 7

Where are the Nr sensors located?

Where does each of the two Nr sensor’s information go?

Answer 7

1 and #2 Accessory Module.

DCU (for PFD display)
AVC

Question 8

What condition will illuminate an MGB OIL HOT caution?

Answer 8

Oil temperatures above 130°C.

Question 9

How many chip detectors are monitored by the chip detector processor?

Answer 9

9 total
(2)1 in each input module
(2)1 in each accessory module
1 in the main module
1 in the IGB
1 in the TGB
(2)1  each engine

Question 10

What is the function of the chip detector processor?

Answer 10

Monitors all 7 power train chip detectors,
commands or disables ‘fuzz-burn’, and
sends information to the DCU for chip caution segments.

Question 11

Under what circumstance will fuzz burn be disabled?

Answer 11

Oil temperatures above 130°C. (140 for TGB)

Question 12

What accessories may be affected by overheating MGB oil?

Answer 12

AC Generators may fail since they are dependent on MGB oil for cooling.

Question 13

What limitations exist when starting the engines with the rotor brake engaged?

Answer 13

Minimum 450 p.s.i. at the rotor brake.
When engines are started and brake released,
1 minute at idle required for even heating of the power turbine blades (to prevent turbine rub).

Question 14

What conditions will cause a ROTOR BRAKE caution to illuminate when WOW?

Answer 14

Rotor brake proximity switches indicate the piston is still engaged
OR
>8+/-2 P.S.I. measured at the pressure switch.

Question 15

What conditions will cause a ROTOR BRAKE caution to illuminate when in flight?

Answer 15

Rotor brake proximity switches indicate the piston is still engaged
AND
>8+/-2 P.S.I. measured at the pressure switch.
In flight, BOTH conditions must be true so that it is not likely that the caution is a false indication.

Question 16

If a TGB CHIP and TGB HOT caution are illuminated, the pilot should land as soon as practical, possible, or immediately?

Answer 16

Immediately

Question 17

Where is the freewheeling unit located?

Answer 17

Input module

Question 18

MGB OUT WARNING illuminates and “GEAR BOX OUT” audio when?

Answer 18

less than 5P.S.I. at the input manifold

AND below 24 P.S.I. at the last jet.

Question 19

MGB PRES WARNING illuminates and “GEAR BOX PRESSURE” audio when?

Answer 19

less than 35P.S.I. at the input manifold

AND below 24 P.S.I. at the last jet.

Question 20

MGB PRESS Caution illuminates?

Answer 20

less than 45P.S.I. at the input manifold

OR below 24 P.S.I. at the last jet.