Volume 4. Propellers and Small Gas Turbines

1. The term "No. 320 grit" refers to which feature of sandpaper?

Type

Strength

Coarseness

Flexibility

2. Which 54H60-91 propeller subassembly transmits engine torque to the propeller blades?

Barrel

Control

Low pitch stop

Pitchlock requlator

3. On the 54H60-91 propeller, which component provides a means for balancing the propeller?

Deicer cnotact ring holder

Hub mounting bulkhead

Front spinner

Afterbody

4. On the 54H60-91 propeller, during normal porpeller operation, the output of which pumps is used?

Main pressure and main scavenge

Standby pressure and main scavenge

Auxiliary pressure and main pressure

Auxiliary pressure and auxiliary scavenge

5. What component in the T56 engine coordinator provides reference signals to the electronic TD amplifier that are proportional to the desired TIT?

Feather shaft

Potentiomether

65* microswitch

66* microswitch

6. When attempting to unfeather the 54H60-91 propeller in flight, where must the throttle be positioned?

Any throttle position

Above FLT IDLE

At TAKE OFF

At GND IDLE

7. The master synchrophaser board located int the synchrophaser unit contains a master channel and a slave channel. these channels are used by which propellers?

No. 1 and no. 2

No. 2 and no. 3

No. 3 and no. 4

All four propellers

8. On the 54H60-91 propeller, which pitchlock component mechanically holds the stationary and rotating pitchlock ratchets apart during reversing adn unfeatherin operations?

Pitchlock control cam

Pitchlock ratchet piston

Externally threaded ring

Externally splined spacer ring

9. On the 54H60-91 propeller, when the throttle is moved to the GROUND IDLE position, what degree setting does the coordinator pointer indicate on the protractor?

0*

18*

34*

90*

10. On the 54H60-91 propeller, if the main filter becomes clogged, which valve opens to assure continued flow?

Check

Bypass

Low pressure relief

High pressure relief

11. Which type fo special inspection can be used to find minute cracks on a propeller blade?

Magnetic

Purple dye

Magna flux

Spectrometric

12. When you perform a static blade transition check and abnormal noises are detected, the 54H60-91 propeller must be returned to depot. What AFTO form must be documented and accompany the propeller back to depot?

45

95

244

781

13. On the 54H60-91 propeller, which dome assembly part allow the rotating cam to turn while the stationary cam remains in a fixed postion?

Roller shaft

Track slopes

Ball bearings

Roller bearings

14. The purpose fo the 54H60-91 propeller pitchlock assembly is to prevent

The loss of oil pressure

An engine overspedd due to a loss of power

The flow of hydraulic fluid to the pilot valve

An engine ovespeed due to a loss fo hydraulic pressure

15. On the 54H60-91 propeller, during alpha range operation, which cam changes speeder spring tension so the governor pilot valve can maintain 100 percent rpm?

Beta set

Speed set

Backup valve

Beta follow-up

16. If the master propeller fails during synchrophaser governing, the slave propellers follow the master to

A 96% mechanical stop

About a 2% speed change

The mechanical governor setting

The preset master propeller governing setting

17. The 54H60-91 propeller governor speeder spring tension positions the pilot valve to maintain what percent rpm in the beta range?

99 to 103%

104 to 108%

109 to 113%

114 to 118%

18. The condition lever GND STOP position is only effective on the ground because the circuits made in this position are completed throw what switches?

Landing gear touchdown

Low speed ground idle

Landing gear warning

Air start

19. On the 54H60-91 propeller, the output of what pump is sufficient to supply hydraulic pressure for nomal propeller operation?

Auxiliary pressure

Standby pressure

Backkup pressure

Main pressure

20. On the 54H60-91 propeller, what forces the stop levers on the low pitch stop to move outward?

Wedge

Servo valve

Dome piston

Hydraulic pressure

21. On the 54H60-91 propeller, during feather operation, between approximately what psi are the pressure cutout switch contacts opened?

0 to 200

300 to 500

600 to 800

900 to 1,100

22. On the 54H60-91 propeller, which component delivers the actual propeller blade angle from the blade to the control assembly?

Microadjusting ring

Beta feedback shaft

Blade segment gear

Blade bushing

23. On the 54H60-91 propeller, which component is used in place of a shim plate on the No. 1 blade?

Beveled thrust washer

Stationary ratchet

Beta segment gear

Blade barrel shim

24. To reduce the noise and vibration levels, synchrophasing mode of governing maintains all the propellers at

Identical speeds and the same blade phase angles

Different speeds and the same blade phase angles

Identical speeds and optimum blade phase angles

Different speeds and optimum blade phase angles

25. On the 54H60-91 propeller, to avoid being crushed after emoving the dome shell during dome piston seal replacement, you should keep your fingers away from the

Dome shell

Cam tracks

Dome piston

Seal area of the piston

26. On the 54H60-91 propeller, after the new packings are in place during dome piston seal replacement, you need to turn them so what color faces outward?

Red

Blue

Green

White

27. When used for ground operation, the SGT engine can be installed on

Pods

An H-frame

A two-wheel trailer

A four-wheel trailer

28. On the 54H60-91 propeller, which valve, contained in the valve housing, controls the flow of hydraulic fluid to and from the dome assembly?

Standby

Feather

Backup

Pilot

29. On the 54H60-91 propeller, when the backup valve is opened, the hydraulic pressure routed to the governoor pilot valve is used for which operation?

Pitchlock

Standby

Reverse

Airstart

30. On the 54H60-91 propeller, the funcition of the low pitch stop is to prevent the

Propeller barrel from decreasing blade angle below 23.3* +_ .5*

Dome piston from decresing blade angle below 23.3* +_ .5*

Propeller barrel from decreasing blade angle below 34* +_ .5*

Dome piston from dereasing blade angle below 34* +_ .5*

31. On a GTCP165 engine shutdown, what valve closes to ensure fuel-flow is terminated?

Poppet

Scheduling

Fuel flow divider

Fuel shutoff solenoid

32. On the 54H60-91 propeller, when feathering the propeller, what acts on the mechanical linkage to open the feather actuating valve?

Throttle

Beta shaft

Pilot valve

Manual feather cam

33. How much change in rpm does the compensating network in the synchrophaser unit allow the speed bias motor to correct?

2%

4%

6%

8%

34. On the 54H60-91 propeller, wen performing blade repair if blade damage was due to propeller blade impact, you must remove all traces of the damage, and then, using emery cloth, remove an additional

0.002 inch

0.004 inch

0.020 inch

0.040 inch

35. When the ambient temperature is greater than 65*F and a patch is bonded to the blade fairing, what is the recommended drying time before running the repaired propeller on the aircraft engine?

24 hours

48 hours

5 days

7 days

36. On an GTCP165 engine, turbine discharge temperature is controlled by the

PMG

Governor

Pneumatic thermostat

Fuel flow divider valve

37. On the 54H60-91 popeller, what is the function of the differential gear train assembly?

Drives the main and standby pressure pumps

Controls operation of the pilot valve and serves as an electrical ground

Drives the rotation sleeve when the throttle is positioned in the beta range

Transmits blade angle movement to the valve housin and drives the propeller governor flyweights

38. On the 54H60-91 propeller, during feathering operation, the feather valve is positioned to meter hydraulic fluid to the

Aft end of the dome piston

Forward end of the dome piston

Decreased-pitch side of the pilot valve

Increased-pitch side of the pilot valve

39. To calculate the required weight change when u use the 192A spectrum analyzer, you will need to plot the data on a

Balance sensitivity chart

Solution screen printout

Balance chart worksheet

Weight balance sheet

40. When balancing a 54H60-91 propeller, the velocimeter is secured to the forward side of the RGB at what position (as viewed from the rear)?

12 o'clock

9 o'clock

6 o'clock

3 o'clock

41. The impeller wheel and tow turbine wheels in the turbine setion of the GTCP165 engine are connected by

Tie bolts

Helical splines

A common shaft

A gear reduction gerbox

42. On the 54H60-91 propeller, which is a function of the the pitchlock regulator?

Stops the dome piston from increasing blade angle above 23.3

Prevents the blades from decreasing pitch if hydraulic pressure is lost

Prevents cam bearing rollers from bottoming out in the track slopes

Prevents the propeller from going into the beta range when the throttle is positioned in alpha range

43. On the 54H60-91 propeller, which valve sets and maintains a pressure differential of about 100 psi between system pressure and the increase- or decrease-pitch pressure?

Check

Bypass

Low-pressure relief

High-pressure relief

44. On the 54H60-91 propeller, when repairing a propeller blade heater, what is the maximum number of wires that can be spliced in any one heater?

4

6

8

10

45. On the 54H60-91 propeller, propeller balancing is not required if the propeller imbalance is at or below what level?

0.2 IPS

0.4 IPS

0.2 degrees

0.4 degrees

46. On the 54H60-91 propeller, hydraulic fluid is directed from the directed from the pump housing to the barrel assembly through what component?

Valve housing

Low pich stop

Transfer bearing

Pitchlock regulator

47. When performing the blade tracking inspection on the 54H60-91 propeller, the calculated difference in blade tracks shouldnot exceed what limit?

1/16 inch

3/16 inch

5/16 inch

7/16 inch

48. On the 54H60-91 propeller, if a nick is found on the metal protion of the blade when performing a blade inspection, which tool is used to measure the depth of the damage?

Internal caliper

Inside micrometer

Blade checking indicator

Ruler with 1/64" increments

49. On the 54H60-91 propeller, what function is a task of the low pitch stop assembly?

Prevents the popeller from goin in to the beta range when the throttle is positioned in the alpha range

Limits cam travel and prevents the propeller from exceeding feather and reverse balde angles

Prevents the blades from decreasing pitch if an overspeed condition occurs

Transmits engine torque to the blades

50. Which switch, located in the control quadrant, activates the 54h-60-91 propeller governor speed bias servo assebly as the throttle is moved into the blight idle gate?

Beta indicator

Landing gear warning

Low speed ground idle

Synchrophaser disarming

51. On the 54H60-91 propeller, which type of valve opens to allow the output of the standby pump to combine with the output of the main pump?

Check

Bypass

Low pressure relief

High pressure relief

52. On the 54H60-91 propeller, what is the minimum psi required to release the feather latches and allow the piston to move forward?

200

400

600

800

53. For the R391 Dowty propeller, during flight operation, what directs the PCU to meter fine and coarse pitch oil to maintain 1020.7 rpm?

RVDTS

FADEC

GBE valve solenoid

PUAD

54. On the R391 Dowty propeller, what does the DITU use to monitor itself for malfunctions?

BIT

ECBU

FADEC

RVDTS

55. On a GTCP165 engine, which component shuts the engine down if the oil pressure drops below the safe minimum operating limit?

Oil/air cooler

Oil filter assembly

Oil pressure switch

Oil pressure regulator valve

56. On the 54H60-91 propeller, which pump is used to feather or unfeather the propeller during static propeller operation?

Main

Backup

Standby

Auxiliary

57. Which is a function of normal governing?

Blade phase angles

Propeller reindexing

Throttle anticipation

Identical propeller speeds

58. What R391 Dowty propeller assembly part provides an aerodynamic faring over the aft section of the hub?

Backplate

Rear spinner

Front spinner

Afterbody assemblies

59. What type of sump design is the oil system on a GTCP165 engine?

Wet

Dry

Hot

Cold

60. When performing a loose blade inspection on the 54H60-91 propeller, fore-and-aft play should not exceed what limit?

1/4 inch

1/2 inch

3/4 inch

1 inch

61. During 54H60-91 propeller dynamic balancing, the propeller balance analyzer receive its two inputs from

The forward and rear engine lord mounts

The hub mounting bulkhead and quadrant

A velocimeter and the magnetic pulse generator

An accelerometer and a NTS switch

62. During normal GTCP165 engine shutdown, what circuit trips to stop the engine?

100-percent circuit

110-percent circuit

Load-control circuit

Speed-switch control circuit

63. On the 54H60-91 propeller, what prevents engagement of the stationary and rotating retchets at blade angles below 25* and above 55*?

An overspeed of 103.5%

The pitchlock control cam

A loss fo hydrulic pressure

Increase- or decrease pitch pressure

64. What is coordinated by the throttle in the controllable pitch range?

Blade pitch and engine fuel flow

Blade pitch and temperature limiting

Engine fuel flow and constant speed governing

Temperature limiting and constant speed governing

65. The pulse generator inputs to the synchrophaser unit are used only

To drive the feedback potentiometer

As a backup for throttle anticipation

When a master propeller is selected

To indicate actual rpm

66. Which component controls the R391 Dowty propeller blade angle by direction engine oil flow through the beta tube to the cylinder and piston?

PCU

GBE valve

PUAD

GMAD

67. Which R391 Dowty propeller component routes engine oil to and from the cylinder and piston?

Beta tube

GBE valve

PUAD

GMAD

68. For the R391 Dowty propeller, the feather valve is located inside the

PCU

GBE valve

PUAD

GMAD

69. On the 54H60-91 propeller, which cam disarms the NTS system linkage when the throttle is positioned in teh beta range?

Manual feather

Beta follow up

Speed set

Beta set

70. On the 54H60-91 propeller, between the blade angles of 25* and 55*, what will keep the rotation and stationary ratchets disengaged?

An overspeed of 103.5%

The pitchlock control cam

A loss fo hydrulic pressure

Increase- or decrease pitch pressure

71. As the 54H60-91 propeller feathers, the output of which pump decreases (drops off)?

Auxiliary pressure

Auxiliary scavenge

Main scavenge

Feather

72. On the 54H60-91 propeller, in the mechanical governing mode, what causes the pilot valve to move and set propeller speed?

Throttle movement

Speeder spring or flyweights

Beta set cam and beta follow-up cam

Speed set cam and manual feather cam

73. Mechanical governing provides the foundation fo rwhat other propeller governing modes?

Synchrophasing and beta range

Normal and synchrophasing

Normal and beta range

Alpha and beta range

74. During normal governign operation, what stabilizes the propeller governor during rapid throttle movements?

Tachometer generator

Feedback potentiometer

Speed stabilization circuit

Throttle anticipation circuit

75. For the R391 Dowty propeller, what component(s) relay propeller blade angle to the FADEC units

PCU

PUAD

GBE valve solenoid

RVDTS

76. On the 54H60-91 propeller, during an underspeed condition, what moves the pilot valve?

Decreased hydraulic pressure

Increased hydraulic pressure

Speeder spring

Flyweights

77. What R391 Dowty propeller component translates piston and shaft movement to vary propeller blade angle?

Hub

Beta tube

Operating pin

Adjustment washer

78. On the 54H60-91 propeller, which valve is a backup in case the feather valve fails during feathering operation?

Pilot

Feather solenoid

Feather actuating

Standby pump check

79. The fuel governing check switches are used to reset the propeller governor t what percentage of rpm in the alpha range?

100%

102%

104%

106%

80. On the 54H60-91 propeller speed bias motor, when the control winding boltage is different from the reference-winding voltage, what results?

Throttle anticipation potentiometer speeds up or slows down the engine

Speed bias motor rotates, and increases or decreases blade angle

Speed bias sevo control locks the clutch and brake unit

Feedback potentiomether recenters the speed bias motor

81. How many slave channels are contained on the master synchrophaser board in the synchrophaser unit?

One

Two

Three

Four

82. For the R391 Dowty propeller, what component provides blade angle feedback to the FADEC by two RVDT?

PCU

GBE valve

PUAD

GMAD

83. Where is the pickup portion of the pulse generator located?

No. 1 blade

Pump housing

Valve housing

Deicer contact ring holder assembly

84. On an GTCP165 engine, the accessory drive section forward housing provides mounts for the components, which include furel control unit, oil pump assembly, oil filter element, vane-axial fan assembly, and

Ignition exciter

Fuel/oil cooler

Air/oil cooler

PMG

85. On an GTCP165 engine, air is compressed by the single-stage centrifugal compressor assembly, and then discharged into

The diffuser case

The turbine plenum

The load control valve

A vaned deswirl assembly

86. On the 54H60-91 propeller, which component is the primary electical ground for energizing the feather override holding coil?

Feather relay

Feather solenoid

Pressure cutout switch

PCBS

87. Which two cams, on the alpha shaft, control the 54H60-91 propeller unfeathering operation?

Manual feather and pressure cutout backup switch

Speed set and pressure cutout backup switch

Speed set and beta follow-up

Manual feather and beta set

88. On a GTCP165 engine, which signals are used by the furl control unit to control engine operation?

Pt0 and Pt7

Engine speed and turbine inle temperature

Ambient inlet pressure and trubine exhaust pressure

Engine speed and pneumatic thermostat (load control) air pressure

89. On the 54H60-91 propeller, during beta range operation, the rotation of which cam moves the mechanical linkage to center the governor pilot valve?

Beta set

Speed set

Backup balve

Beta follow-up

90. The modulating and shutoff valve on a GTCP165 engine will be fully open at what percent rpm?

60

70

80

90

91. Which board in the synchrophaser unit receives input signals that are compared together, modified, and used to control the speed bias motors?

Double slave

Power supply

Power amplifier

Master synchrophaser

92. On a GTCP165 engine, the speed switch control does not control the engine during

Startup

Acceleration

Loaded operation

No-load operation

93. On the 54H60-91 propeller, after the NTS system actuator rod positins the mechanical linkage in the valve housing when a negative torque condition occurs, what component is shifted?

Speed set cam

Feather valve

Beta set cam

Pilot valve

Volume 4. Propellers and Small Gas Turbines

1. The term "No. 320 grit" refers to which feature of sandpaper?

2.

What first name or nickname would you like us to use?

2. Which 54H60-91 propeller subassembly transmits engine torque to the propeller blades?

3. On the 54H60-91 propeller, which component provides a means for balancing the propeller?

4. On the 54H60-91 propeller, during normal porpeller operation, the output of which pumps is used?

5. What component in the T56 engine coordinator provides reference signals to the electronic TD amplifier that are proportional to the desired TIT?

6. When attempting to unfeather the 54H60-91 propeller in flight, where must the throttle be positioned?

7. The master synchrophaser board located int the synchrophaser unit contains a master channel and a slave channel. these channels are used by which propellers?

8. On the 54H60-91 propeller, which pitchlock component mechanically holds the stationary and rotating pitchlock ratchets apart during reversing adn unfeatherin operations?

9. On the 54H60-91 propeller, when the throttle is moved to the GROUND IDLE position, what degree setting does the coordinator pointer indicate on the protractor?

10. On the 54H60-91 propeller, if the main filter becomes clogged, which valve opens to assure continued flow?

11. Which type fo special inspection can be used to find minute cracks on a propeller blade?

12. When you perform a static blade transition check and abnormal noises are detected, the 54H60-91 propeller must be returned to depot. What AFTO form must be documented and accompany the propeller back to depot?

13. On the 54H60-91 propeller, which dome assembly part allow the rotating cam to turn while the stationary cam remains in a fixed postion?

14. The purpose fo the 54H60-91 propeller pitchlock assembly is to prevent

15. On the 54H60-91 propeller, during alpha range operation, which cam changes speeder spring tension so the governor pilot valve can maintain 100 percent rpm?

16. If the master propeller fails during synchrophaser governing, the slave propellers follow the master to

17. The 54H60-91 propeller governor speeder spring tension positions the pilot valve to maintain what percent rpm in the beta range?

18. The condition lever GND STOP position is only effective on the ground because the circuits made in this position are completed throw what switches?

19. On the 54H60-91 propeller, the output of what pump is sufficient to supply hydraulic pressure for nomal propeller operation?

20. On the 54H60-91 propeller, what forces the stop levers on the low pitch stop to move outward?

21. On the 54H60-91 propeller, during feather operation, between approximately what psi are the pressure cutout switch contacts opened?

22. On the 54H60-91 propeller, which component delivers the actual propeller blade angle from the blade to the control assembly?

23. On the 54H60-91 propeller, which component is used in place of a shim plate on the No. 1 blade?

24. To reduce the noise and vibration levels, synchrophasing mode of governing maintains all the propellers at

25. On the 54H60-91 propeller, to avoid being crushed after emoving the dome shell during dome piston seal replacement, you should keep your fingers away from the

26. On the 54H60-91 propeller, after the new packings are in place during dome piston seal replacement, you need to turn them so what color faces outward?

27. When used for ground operation, the SGT engine can be installed on

28. On the 54H60-91 propeller, which valve, contained in the valve housing, controls the flow of hydraulic fluid to and from the dome assembly?

29. On the 54H60-91 propeller, when the backup valve is opened, the hydraulic pressure routed to the governoor pilot valve is used for which operation?

30. On the 54H60-91 propeller, the funcition of the low pitch stop is to prevent the

31. On a GTCP165 engine shutdown, what valve closes to ensure fuel-flow is terminated?

32. On the 54H60-91 propeller, when feathering the propeller, what acts on the mechanical linkage to open the feather actuating valve?

33. How much change in rpm does the compensating network in the synchrophaser unit allow the speed bias motor to correct?

34. On the 54H60-91 propeller, wen performing blade repair if blade damage was due to propeller blade impact, you must remove all traces of the damage, and then, using emery cloth, remove an additional

35. When the ambient temperature is greater than 65*F and a patch is bonded to the blade fairing, what is the recommended drying time before running the repaired propeller on the aircraft engine?

36. On an GTCP165 engine, turbine discharge temperature is controlled by the

37. On the 54H60-91 popeller, what is the function of the differential gear train assembly?

38. On the 54H60-91 propeller, during feathering operation, the feather valve is positioned to meter hydraulic fluid to the

39. To calculate the required weight change when u use the 192A spectrum analyzer, you will need to plot the data on a

40. When balancing a 54H60-91 propeller, the velocimeter is secured to the forward side of the RGB at what position (as viewed from the rear)?

41. The impeller wheel and tow turbine wheels in the turbine setion of the GTCP165 engine are connected by

42. On the 54H60-91 propeller, which is a function of the the pitchlock regulator?

43. On the 54H60-91 propeller, which valve sets and maintains a pressure differential of about 100 psi between system pressure and the increase- or decrease-pitch pressure?

44. On the 54H60-91 propeller, when repairing a propeller blade heater, what is the maximum number of wires that can be spliced in any one heater?

45. On the 54H60-91 propeller, propeller balancing is not required if the propeller imbalance is at or below what level?

46. On the 54H60-91 propeller, hydraulic fluid is directed from the directed from the pump housing to the barrel assembly through what component?

47. When performing the blade tracking inspection on the 54H60-91 propeller, the calculated difference in blade tracks shouldnot exceed what limit?

48. On the 54H60-91 propeller, if a nick is found on the metal protion of the blade when performing a blade inspection, which tool is used to measure the depth of the damage?

49. On the 54H60-91 propeller, what function is a task of the low pitch stop assembly?

50. Which switch, located in the control quadrant, activates the 54h-60-91 propeller governor speed bias servo assebly as the throttle is moved into the blight idle gate?

51. On the 54H60-91 propeller, which type of valve opens to allow the output of the standby pump to combine with the output of the main pump?

52. On the 54H60-91 propeller, what is the minimum psi required to release the feather latches and allow the piston to move forward?

53. For the R391 Dowty propeller, during flight operation, what directs the PCU to meter fine and coarse pitch oil to maintain 1020.7 rpm?

54. On the R391 Dowty propeller, what does the DITU use to monitor itself for malfunctions?

55. On a GTCP165 engine, which component shuts the engine down if the oil pressure drops below the safe minimum operating limit?

56. On the 54H60-91 propeller, which pump is used to feather or unfeather the propeller during static propeller operation?

57. Which is a function of normal governing?

58. What R391 Dowty propeller assembly part provides an aerodynamic faring over the aft section of the hub?

59. What type of sump design is the oil system on a GTCP165 engine?

60. When performing a loose blade inspection on the 54H60-91 propeller, fore-and-aft play should not exceed what limit?

61. During 54H60-91 propeller dynamic balancing, the propeller balance analyzer receive its two inputs from

62. During normal GTCP165 engine shutdown, what circuit trips to stop the engine?

63. On the 54H60-91 propeller, what prevents engagement of the stationary and rotating retchets at blade angles below 25* and above 55*?

64. What is coordinated by the throttle in the controllable pitch range?

65. The pulse generator inputs to the synchrophaser unit are used only

66. Which component controls the R391 Dowty propeller blade angle by direction engine oil flow through the beta tube to the cylinder and piston?

67. Which R391 Dowty propeller component routes engine oil to and from the cylinder and piston?

68. For the R391 Dowty propeller, the feather valve is located inside the

69. On the 54H60-91 propeller, which cam disarms the NTS system linkage when the throttle is positioned in teh beta range?

70. On the 54H60-91 propeller, between the blade angles of 25* and 55*, what will keep the rotation and stationary ratchets disengaged?

71. As the 54H60-91 propeller feathers, the output of which pump decreases (drops off)?

72. On the 54H60-91 propeller, in the mechanical governing mode, what causes the pilot valve to move and set propeller speed?

73. Mechanical governing provides the foundation fo rwhat other propeller governing modes?

74. During normal governign operation, what stabilizes the propeller governor during rapid throttle movements?

75. For the R391 Dowty propeller, what component(s) relay propeller blade angle to the FADEC units

76. On the 54H60-91 propeller, during an underspeed condition, what moves the pilot valve?

77. What R391 Dowty propeller component translates piston and shaft movement to vary propeller blade angle?