Tail Rotor Servo Components

Question 1

Tail rotor servo

Answer 1

Mounted to the tail gear box either output shaft facing tail rotor
Converts mechanical input to pressure control output

Question 2

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Answer 2

Outboard: 1st stage hydraulics
Inboard: Utility hydraulic at 3000 psi 2nd

Question 3

Power piston

Answer 3

Dual head, converts hydraulic pressure into mechanical motion

Question 4

Pilot valve

Answer 4

Allows fluid transfer to control the power piston

Question 5

Bypass valve

Answer 5

Prevents hydraulic lock when the servo is unpressurized with no inputs

Question 6

Transfer manifold

Answer 6

Mounted to tail gearbox between Tail gearbox and Tail rotor servo
Contains four quick disconnects
Allows the tail rotor servo to be removed without disconnecting

Question 7

Center spring

Answer 7

Mounted to tail rotor servo housing
Centers tail rotor servo in cruise flight position in the event of mechanical flight control separation

Question 8

Rotary couplings

Answer 8

Right side at pylon hinge
Upper- First stage
Lower- second stage
Allows folding w/o disconnecting hydraulic lines

Question 9

Finned tubing

Answer 9

After section vertical portion of tail pylon
One section, 5 ft long w/ 3 finned areas
Cools first stage tail rotor servo return fluid