Robinson Helicopter Company RTR 660 (Number R00015LA). Maintenance Manual (2012)

64-40 Tail Rotor Hub

64-41 Bearing Replacement

Refer to R66 Illustrated Parts Catalog (IPC) Figure 64-1.

A. Removal

1. Remove tail rotor assembly per Section 64-10.

2. Remove tail rotor blades per Section 64-20.

3. Refer to Figure 64-5. Press bearing(s) from hub using MT556-11 bearing removal

(and installation) tools.

B. Installation

1. Inspect tail rotor hub per Section 64-42.

CAUTION

Elastomeric bearings are a slight press fit in tail rotor hub bores.

Inspect bores for fretting; if fretting is detected, hub is unairworthy.

2. Refer to Figure 64-6. Using Q-tip, apply light coat of approved primer per Section

20-70 to bottom of hub bearing bore. Apply a thin line of primer to center of bearing

outside diameter. While primer is wet, press bearing into hub using MT556-11

bearing removal and installation tools. Wipe away excess primer.

3. Repeat steps for second bearing, as required.

64-42 Inspection

1. Remove tail rotor blades per Section 64-20, and inspect blades per Section 64-30.

2. Remove elastomeric bearings per Section 64-41.

3. Clean G062-1 tail rotor hub using approved solvent per Section 20-70.

4. Visually inspect for indications of damage, wear, nicks, dings, and corrosion. Check

arms for straightness, bolt holes for elongation, and bearing bores for fretting or galling.

Corrosion is not permitted on clamp-up surfaces.

5. For suspect areas, locally remove paint from hub using approved paint stripper per

Section 20-70; dye penetrant or fluorescent penetrant inspect per Section 20-40.

6. Touch-up bare metal using approved materials per Section 20-70.

7. Install elastomeric bearings per Section 64-41.

8. Install tail rotor blades per Section 64-20.

25 OCT 2010

Chapter 64 Tail Rotor

Page 64.13

CHAPTER 65

TAIL ROTOR DRIVE SYSTEM

65-00 Description

The tail rotor driveline consists of an intermediate shaft running aft from the main gearbox and

a long tail rotor driveshaft which runs the length of the tailcone. Flexible couplings are located

at both ends of the intermediate shaft. The long tail rotor driveshaft has a support bearing at

its front end and a damper bearing approximately one-third of the way aft on the shaft. The

cooling fan is mounted to the intermediate shaft. The tail gearbox contains a single 90º splash-

lubricated spiral-bevel gearset which increases speed to tail rotor RPM.

65-10 Tail Rotor Drive Fan Shaft

Refer to R66 Illustrated Parts Catalog (IPC) Figure 65-1.

CAUTION

Do not damage F196-1 fan shaft aft yoke or G174-1 fanwheel

assembly mid plate during fan shaft removal or installation.

A. Removal

1. Remove tailcone cowling assembly per Section 53-23.

2. Refer to Figure 65-1. Remove hardware securing F252-1 strut assembly to upper frame

assembly and remove strut.

3. Remove hardware securing intermediate C947-3 flex plate assembly to F196-1 (tail rotor)

fan shaft aft flange and D224-3 tail rotor drive shaft assembly forward yoke, noting

hardware removed. Remove flex plate, and temporarily support aft portion of fan shaft.

4. Remove hardware securing fan shaft to forward C947-3 flex plate assembly.

5. Remove hardware securing fan shaft to G174-1 fanwheel assembly. Carefully pull

fan shaft forward through fanwheel assembly, rotating yoke as necessary. Remove

temporary support.

Installation

1. Refer to Figure 65-1. Route F196-1 fan shaft aft through fanwheel assembly, rotating

yoke as necessary. Install hardware securing fan shaft to G174-1 fanwheel assembly.

Standard torque nuts and palnuts per Section 20-32, and torque stripe per Figure 5-1.

2. Install hardware securing fan shaft to forward C947-3 plate assembly. Standard torque

nuts and palnuts per Section 20-32, and torque stripe per Figure 5-1. Shim tail rotor

driveline per Section 65-30.

3. Install F252-1 strut assembly and hardware securing strut to upper frame assembly.

Standard torque nuts per Section 20-32 and torque stripe per Figure 5-1.

4. Install tailcone cowling assembly per Section 53-23.

Chapter 65 Tail Rotor Drive System

Page 65.1

65-20 Tail Rotor Drive Shaft Assembly

Refer to R66 Illustrated Parts Catalog (IPC) Figure 65-3.

A. Removal

1. Remove C023 tailcone assembly per Section 53-40.

2. Refer to Figure 65-1. Remove hardware securing F172-1 bearing assembly to F193-1

hanger.

3. Refer to Figure 65-3. Using a 3-foot extension, remove bolts securing C041-12 damper

assembly arm to D072-1 bulkhead assembly angle. Support forward end of D224-3

drive shaft assembly.

4. Remove hardware securing A558-2 cover to tailcone and remove cover.

5. Support aft end of drive shaft, and remove hardware securing drive shaft to aft C947-3

plate assembly, noting hardware removed. Carefully pull drive shaft forward through

tailcone.

Installation

1. Refer to Figure 65-1. Route D224-3 drive shaft assembly through inside of tailcone.

Support drive shaft as required.

2. Install hardware securing drive shaft to aft C947-3 plate assembly, as removed, and

remove support. Standard torque fasteners per Section 20-32 and torque stripe per

Figure 5-1. Install A558-2 cover.

3. Refer to Figure 65-3. Remove forward A231-1 (tailcone) plug assembly. Estimate

longitudinal gap (or interference) between C041-12 damper assembly arm and D072-1

bulkhead assembly angle. If gap (or interference) exceeds 0.12 inch, contact RHC

Technical Support. If gap (or interference) is less than 0.12 inch, verify correct damper

orientation. Using a 3-foot extension, install bolts securing damper to bulkhead angle.

Standard torque bolts per Section 20-32 and torque stripe per Figure 5-1. Install plug

assembly.

4. Install hardware securing F172-1 bearing assembly to F193-1 hanger, and remove

support. Standard torque bolts per Section 20-32 and torque stripe per Figure 5-1.

5. Install C023 tailcone assembly per Section 53-40.

Chapter 65 Tail Rotor Drive System

Page 65.3

65-21 Runout

1. Remove (5) A231-1 (tailcone) plug assemblies.

2. Assemble MT260-6 tail rotor drive shaft runout tool and a calibrated dial indicator.

3. Refer to Figure 65-2. Using appropriate combination of extension(s), insert tool through

tailcone inspection hole. Verify foot squarely contacts tail rotor drive shaft when pressing

dial indicator firmly against inspection hole edges. Have a second person rotate rotor

system by turning tail rotor hub.

4. Rotate rotor system slowly, smoothly, and for several revolutions until the technician is

able to determine the average indicated movement. Maximum runout is 0.025 inch.

5. Repeat steps at each inspection hole. Record values as required (recommended during

100-hour or annual inspection).

FIGURE 65-3 DAMPER ORIENTATION

Chapter 65 Tail Rotor Drive System

Page 65.5

65-22 Damper Assembly

Refer to R66 Illustrated Parts Catalog (IPC) Figure 65-7.

A. Disassembly

1. Remove tail rotor drive shaft per Section 65-20, if not previously accomplished.

2. Refer to Figure 65-4. Remove hardware securing C041-11 bearing assembly and

C041-13 arm to C041-3 link.

Inspection and Assembly

1. Refer to Figure 65-4. Inspect condition of components. Verify no wear on Teflon®

(dark gray) face of C041-5 washers. Verify no wear or grooves on A141-36 washers,

A141-37 washers, and link. Replace components as required.

CAUTION

Install C041-5 washers with Teflon® face toward C041-3 link and

toward A141-36 washer (remove protective coating, if installed).

CAUTION

Install C041-6 spring washer with concave face toward C041-5

washer.

2. Assemble damper. Install hardware securing C041-11 bearing assembly and C041-

13 arm to C041-3 link. Align component holes on A041-10 dowel pin(s). Standard

torque nuts and palnuts per Section 20-32 and torque stripe per Figure 5-1.

3. Attach a calibrated spring scale to Point A. Holding link, verify force required to

rotate arm about Point B is 3.5 - 5.8 lb. Adjust as required per Part C.

4. Attach a calibrated spring scale to Point B. Holding bearing assembly, verify force

required to rotate link about point C is 2.1 - 3.6 lb. Adjust as required per Part C.

C. Friction Adjustment

CAUTION

Do not adjust damper drag by changing bolt torque.

1. Refer to Figure 65-4. If friction is less than required:

a. Disassemble C041-12 damper assembly per Part A. Bend C041-6 spring washers

to 0.065 - 0.078 inch total height; inspect and reassemble damper assembly per

Part B.

b. If friction is less than required after correcting spring washer height, disassemble

damper assembly per Part A. Lap A105-12 journals, as required; inspect and

reassemble damper assembly per Part B.

2. If friction is greater than required:

a. Disassemble damper assembly per Part A. Flatten C041-6 spring washers slightly;

inspect and reassemble damper assembly per Part B.

3. Install tail rotor drive shaft per Section 65-20.

Chapter 65 Tail Rotor Drive System

Page 65.7

65-30 (Tail Rotor Driveline) Intermediate Flex Plate Shimming

NOTE

The tail rotor driveline is shimmed for minimal preload.

Refer to Figure 65-1. If not previously accomplished, remove hardware securing

intermediate C947-3 flex plate assembly to F196-1 (tail rotor) fan shaft aft flange and

D224-3 tail rotor drive shaft assembly forward yoke. Remove flex plate, and temporarily

support aft portion of fan shaft.

Measure flex plate thickness at bonded washers (4 places) to determine average thickness:

(1st place)

inch

(2nd place) +

inch

(3rd place) +

inch

(4th place) +

inch

Total =

inch

Total ÷ 4 =

inch

(Flex plate average thickness)

Position F196-1 fan shaft aft flange arms and D224-3 tail rotor drive shaft assembly

forward yoke flange arms at 3 o’clock and 9 o’clock positions (horizontal). Measure

gap between arms to determine average gap:

(3 o’clock position)

inch

(9 o’clock position) +

inch

Total =

inch

Total ÷ 2 =

inch

(Average gap between flange arms)

Rotate D224-3 tail rotor drive shaft assembly 180º, and repeat step a:

(3 o’clock position)

inch

(9 o’clock position) +

inch

Total =

inch

Total ÷ 2 =

inch

(Average gap between flange arms)

Evaluate flange straightness by calculating the difference between the 3 o’clock positions

in steps 3a and 3b. Also calculate the difference between the 9 o’clock positions in

steps 3a and 3b. If either calculated difference exceeds 0.015 inch, either one or both

flanges are bent and require replacement.

Page 65.8

Chapter 65 Tail Rotor Drive System

65-30 (Tail Rotor Driveline) Intermediate Flex Plate Shimming (continued)

5. Using the smaller average gap from step 3a or 3b, subtract the flex plate average

thickness determined in step 2:

Smaller average gap between flange arms (step 3a or 3b)

inch

Subtract flex plate average thickness (step 2) −

inch

Total =

inch

6. Select shims per Table 65-1 and install intermediate C947-3 flex plate assembly.

Standard torque nuts and palnuts per Section 20-32 and torque stripe per Figure 5-1.

Remove F196-1 (tail rotor) fan shaft temporary support.

WARNING

Shim both arms of flanges equally. All fasteners must meet

torque requirements given in Section 20-33.

Shim required between

Calculated

intermediate C947-3 flex plate

Dimension

and D224-3 tail rotor drive shaft

and F196-1 fan shaft aft flange

forward yoke

NAS1149F0432P washer between forward C947-3 flex plate

assembly and F908-1 yoke assembly and/or F196-1 fan shaft

−0.017 or greater

forward flange may be relocated under nut as required to achieve

negative number

−0.016 / +0.016 inch calculated dimension. Relocate washers as

required, and repeat steps 3 thru 6.

−0.016 / +0.016 in.

None

+0.017 / +0.047 in.

NAS1149F0432P washer

None

+0.048 / +0.079 in.

NAS1149F0432P washer

+0.080 / +0.110 in.

NAS1149F0463P washer

NAS1149F0432P washer

+0.111 / +0.141 in.

NAS1149F0463P washer

NAS1149F0432P washer between forward C947-3 flex plate

assembly and F908-1 yoke assembly and/or F196-1 fan shaft

+0.142 or greater

forward flange may be exchanged with NAS1149F0463P washer as

positive number

required to achieve −0.016 / +0.016 inch calculated dimension.

Exchange washers as required, and repeat steps 3 thru 6.

TABLE 65-1 TAIL ROTOR DRIVELINE

7. Measure fanwheel-to-inlet gaps per Section 79-11.

Chapter 65 Tail Rotor Drive System

Page 65.9

65-40 Tail Rotor Gearbox Assembly

Refer to R66 Illustrated Parts Catalog (IPC) Figure 65-9.

A. Removal

NOTE

Drain tail rotor gearbox oil per Section12-21 prior to gearbox

removal, or keep gearbox vertical after removal to avoid oil

escape thru filler-vent plug.

1. Remove hardware securing push-pull tube assembly to bellcrank assembly.

2. As required, remove tail rotor assembly per Section 64-10. As required, remove hardware

securing bellcrank to tail rotor gearbox assembly output cartridge. Slide (assembled)

bellcrank, pitch control assembly, and pitch links off of gearbox output shaft.

3. Remove hardware securing A558-2 cover to tailcone and remove cover.

4. Support aft end of D224-3 drive shaft assembly, and remove hardware securing gearbox

input yoke to aft C947-3 plate assembly, noting hardware removed.

5. Cut and discard ty-raps as required and disconnect chip detector wiring at plastic

connector.

6. Remove hardware securing gearbox to tailcone casting and remove gearbox.

Installation

1. Position tail rotor gearbox assembly on tailcone casting and install mounting hardware.

Special torque screws per Section 20-33 and torque stripe per Figure 5-1.

2. Connect chip detector wiring at plastic connector and install ty-raps, as required. Cinch

ty-raps until snug without over-tightening, and trim tips flush with heads.

3. Install hardware securing gearbox input yoke to aft C947-3 plate assembly, and remove

support. Shim tail rotor driveline per Section 65-30. Standard torque bolts per Section

20-32 and torque stripe per Figure 5-1. Install A558-2 cover.

4. If removed, slide (assembled) bellcrank assembly, pitch control assembly, and pitch

links onto gearbox output shaft. Install hardware securing bellcrank to gearbox output

cartridge. Standard torque bolts per Section 20-32 and torque stripe per Figure 5-1.

Shim pitch control per Section 67-62, as required.

5. Install hardware securing push-pull tube assembly to bellcrank. Standard torque fastener

per Section 20-32 and torque stripe per Figure 5-1.

6. If removed, install tail rotor assembly per Section 64-10.

7. Service tail rotor gearbox per Section 12-21, as required.

Page 65.10

Chapter 65 Tail Rotor Drive System

65-41 Output Shaft Seal Replacement

Refer to R66 Illustrated Parts Catalog (IPC) Figure 65-13.

Remove tail rotor assembly per Section 64-10.

Remove hardware securing push-pull tube assembly to bellcrank assembly.

Remove hardware securing bellcrank to tail rotor gearbox assembly output cartridge.

Slide (assembled) bellcrank, pitch control assembly, and pitch links off of gearbox output

shaft.

Cut and discard safety wire securing C112-2 cap retaining hardware. Remove hardware

securing cap to gearbox and remove cap with C966-2 seal and C215-133 o-ring.

CAUTION

Do not remove shims between cap and gearbox assembly.

Shims control output shaft drag.

Using hydraulic press, press old seal from cap. Remove and discard o-ring. Clean and

dry cap, especially seal seating surface and o-ring groove.

Verify open face of seal points toward gearbox and press new seal into cap bore 0.160

inches from external surface. Lightly coat new o-ring with A257-22 oil and install in

cap.

Lightly coat output shaft seal seating area with A257-22 lubricant and slide cap onto

shaft. Install hardware securing cap to gearbox and special torque bolts per Section 20-

33. Install 0.032-inch diameter lockwire through hardware and safety in pairs.

Slide (assembled) bellcrank assembly, pitch control assembly, and pitch links onto

gearbox output shaft. Shim pitch control per Section 67-62, as required.

Install hardware securing push-pull tube assembly to bellcrank. Standard torque fastener

per Section 20-32 and torque stripe per Figure 5-1.

10.

Install tail rotor assembly per Section 64-10.

Chapter 65 Tail Rotor Drive System

Page 65.11

65-42 Input Shaft Seal Replacement

Refer to R66 Illustrated Parts Catalog (IPC) Figure 65-13.

Remove tail rotor gearbox per Section 65-40. Tail rotor assembly and pitch control

assembly removal are not required.

Remove and discard cotter pin securing tail rotor input yoke retaining nut. On a suitable

work bench, place a wood block between yoke and gearbox housing to prevent tail rotor

rotation; remove castellated nut, washer, and yoke.

Cut and discard safety wire securing C112-1 cap retaining hardware. Remove hardware

securing cap to gearbox and remove cap with A966-3 seal and C215-140 o-ring.

CAUTION

Do not remove C141-2 washer between cap and bearing.

Using hydraulic press, press old seal from cap. Remove and discard o-ring. Clean and

dry cap, especially seal seating surface and o-ring groove.

Verify open face of seal points toward gearbox and press new seal into cap bore 0.25

inch from external surface. Lightly coat new o-ring with A257-22 oil and install in

cap.

Install cap, and hardware securing cap to gearbox; special torque bolts per Section 20-

33. Install 0.032-inch diameter lockwire through hardware and safety in pairs.

Install input yoke, washer, and castellated nut onto gear shaft. Place wood block

between yoke and gearbox housing to prevent tail rotor rotation, special torque nut per

Section 20-33, and install new MS24665-210 cotter pin.

Install tail rotor gearbox per Section 65-40.

Page 65.12

Chapter 65 Tail Rotor Drive System

CHAPTER 67

FLIGHT CONTROLS

Section

Title

Page

67-00

Description

67.1

67-10

Cyclic Controls

67.1

67-11

Cyclic Control Assembly

67.1

67-12

Cyclic Grip Assembly

67.4

67-13

Cyclic Friction Assembly

67.6

67-20

Collective Control

67.6

67-21

Collective Stick Assembly

67.6

67-22

Collective Friction

67.8

67-30

Jackshaft and Strut Assembly

67.8

67-31

Jackshaft

67.8

67-40

Swashplate

67.9

67-41

Swashplate Tilting Friction Adjustment

67.11

67-42

Upper and Lower Scissor Assemblies

67.11

67-50

Hydraulic System

67.13

67-51

Hydraulic Pump

67.13

67-52

Hydraulic Reservoir

67.14

67-53

Hydraulic Servos

67.15B

67-60

Tail Rotor Controls

67.19

67-61

Pedals

67.19

67-62

Pitch Control

67.20

67-70

Bellcranks

67.21

67-71

C317-5 Bellcrank

67.21

67-72

C317-7 Bellcrank

67.22

67-73

F316-1 Bellcrank

67.22

67-74

A331-4 Bellcrank

67.23

67-75

A120-5 Bellcrank

67.24

MAR 2012

Chapter 67 Flight Controls

Page 67.i

CHAPTER 67

FLIGHT CONTROLS

67-00 Description

Dual controls, which are removable on the left side, are standard equipment. All primary

controls are actuated through push-pull tubes and bellcranks. Bearings used throughout the

control system are either sealed ball bearings or have self-lubricated Teflon® liners.

R66 flight controls operate conventionally. The cyclic stick appears different, but the grip

moves the same as in other helicopters due to the free hinge at the center pivot. The cyclic

grip is free to move vertically allowing the pilot to rest his forearm on his knee if he chooses.

The collective control is also conventional. A twist grip provides input to the engine fuel

control, and raising or lowering the collective provides power turbine governor inputs via an

interconnecting linkage.

Pilot-side tail rotor pedals are adjustable. To adjust, extract quick-release pin on each pedal by

depressing button and pulling. Slide pedal fore or aft to most comfortable of three adjustment

positions, and reinstall quick-release pin. Verify pins secure before flight.

See R66 Pilot's Operating Handbook (POH) Section 7 for instructions to remove (removable)

flight controls.

See Section 67-50 for hydraulic system description.

WARNING

Assembly of flight controls is critical and requires inspection

by a qualified person. If a second person is not available, the

installer must take a 5-minute break prior to inspecting flight

control connections he has assembled.

67-10 Cyclic Controls

Refer to R66 Illustrated Parts Catalog (IPC) Chapter 67.

67-11 Cyclic Control Assembly

A. Removal

1. Refer to Section 6-70. Remove F794-1 (forward) and F794-2 (aft) belly panels,

F680-3 (pilot collective) and F445-1 (forward tunnel) cover assemblies, and F461-1

(collective cross tube) and F463-1 (aft tunnel) cover assemblies. Open upper console,

disconnect OAT gage and hourmeter wiring connectors, and remove radio faceplate.

Remove plastic hole plug from vertical keel panel beneath RH, aft seat.

2. Turn cyclic friction OFF. Gently punch out cyclic friction knob spring pin and remove

knob. Remove hardware securing F444-1 cover assembly to F338-1 box, unsnap

boot, and lift cover assembly to expose wire harness connectors. Disconnect anti-

ice, pitot heat, and ELT switch (if installed) wiring. Snap boot together at top of

cyclic stick to secure cover. Install pin on cyclic friction shaft to retain spacers.

3. Refer to Figure 67-1. Unhook D918-1 cord assembly from C069-8 (cyclic) stick

assembly and D918-2 cord assembly from C177-5 pivot assembly.

4. Disconnect wiring exiting D320-8 stick at connectors near bottom of stick.

MAR 2012

Chapter 67 Flight Controls

Page 67.1

67-11 Cyclic Control Assembly (continued)

A. Removal (continued)

5. Remove hardware securing C121-1 push-pull tube assembly to D320-8 stick

assembly. Remove hardware securing C319-5 torque tube assembly to C177-5

pivot assembly. Move push-pull tube and torque tube assemblies aft, and protect

from scratching.

6. Disconnect, but do not remove, two bolts securing cyclic friction assembly to cabin.

Apply some cyclic friction to keep plates assembled.

7. Remove screws securing F338-1 cyclic box to cabin. Lift and remove cyclic control

assembly with attached cyclic box and friction assembly. Install nuts onto two

cyclic friction assembly bolts, hand tight, to retain bolts and spacers.

8. Remove hardware securing both outboard, vertical F121-5 push-pull tube assemblies

and C130-47 spacer to D696-6 yoke assembly.

9. Remove hardware securing center, vertical F121-7 push-pull tube assemblies to

C958-6 bellcrank.

10. Remove hardware securing G205-1 fork assembly to F334-1 support assembly.

11. Pull D175-5 cyclic pivot assembly (torque tube, yoke, bellcranks, fork, and push-pull

tube assembly) aft through belly.

Installation

1. Refer to Figure 67-1. Verify center-to-center distance between rod end and spherical

bearings in G205-5 fork is 5.40 ± 0.03 inches; adjust as required. Standard torque

jam nut and palnut per Section 20-32. Install C175-5 cyclic pivot assembly (torque

tube, yoke, bellcranks, fork, and push-pull tube assemblies) thru aft belly.

2. Connect G205-1 fork assembly to F326-1 bellcrank and standard torque bolt per

Section 20-32.

3. Connect lower end of center F121-7 push-pull tube to C958-6 bellcranks and standard

torque bolt per Section 20-32.

4. Connect lower ends of both outboard F121-6 push-pull tubes to D696-6 yoke using

a NAS6605-46 bolt and C130-47 spacer and standard torque per Section 20-32.

Install plastic hole plug in vertical keel panel beneath RH, aft seat.

5. Remove temporary nuts from cyclic friction assembly bolts. Position cyclic box

with attached cyclic control and friction assemblies between keel panels. Install all

screws fastening cyclic box to cabin. Fasten cyclic friction assembly to cabin and

standard torque bolts per Section 20-32.

6. Connect C319-5 torque tube assembly to C177-5 pivot and standard torque bolts

per Section 20-32.

7. Connect forward end of C121-1 push-pull tube to D320-8 cyclic stick and standard

torque bolts per Section 20-32.

25 OCT 2010

Chapter 67 Flight Controls

Page 67.3

67-11 Cyclic Control Assembly (continued)

B. Installation (continued)

8. Connect all electrical plugs at bottom of cyclic stick. Ensure protective sleeving

covers maximum amount of wiring possible and sleeving ends are secured with

lacing tape.

9. Connect D918-1 cord to D320-8 cyclic stick. Connect D918-2 cord to C177-5

pivot.

10. Move cyclic control through all positions and verify operating and no binding.

11. Install radio face plate, connect OAT gage and hourmeter wiring connectors, and ty-

rap as required. Close and secure upper console.

12. Connect cyclic box cover anti-ice, pitot heat (if installed), and ELT (if installed) switch

wiring connectors and secure cover.

13. Install cyclic friction knob and secure with spring pin. Close and secure cyclic stick

boot.

14. Install F794-1 (forward) and F794-2 (aft) belly panels, F680-3 (pilot collective) and

F445-1 (forward tunnel) cover assemblies, and F461-1 (collective cross tube) and

F463-1 (aft tunnel) cover assemblies.

67-12 Cyclic Grip Assembly

A. Removal

NOTE

This may be accomplished without removal of complete cyclic

assembly from rotorcraft.

Remove forward belly panel.

Refer to Figure 67-1. Disconnect wiring connectors attached to wiring exiting base

of D320-8 cyclic stick. Using pin extractor, remove pins from housings (wires

112, 138, & 355 may remain installed) and retain housings. Remove lacing tape

from both ends of protective sleeving covering wires exiting base of stick assembly.

Attach a 3 foot length of safety wire or wire lacing tape to one removed pin.

As required, rotate grip assembly by pushing in on spring-loaded stop pin so exposed

wire loom does not wrap around top of D320-8 cyclic stick. Remove circular plug,

D684-1 spring, cotter pin, castellated nut, and washer where grip assembly attaches

to D320-8 cyclic stick.

Remove grommet atop cyclic stick at grip assembly wiring entrance. With a soft-

faced hammer, gently tap cyclic grip assembly pivot and remove grip assembly and

attached wiring from stick assembly. Ensure safety wire or lacing attached to internal

wiring protrudes from top and bottom of stick assembly. Also, ensure pivot bearings

remain with stick assembly.

NOTE

Do not damage bearings while removing.

Page 67.4

Chapter 67 Flight Controls

25 OCT 2010

67-12 Cyclic Grip Assembly (continued)

Installation

Refer to Figure 67-1. Ensure protective sleeving covers wires exiting grip assembly

with one grommet in grip and one (for cyclic stick) on wire bundle (spare grommets

may be installed if desired).

Slide grip assembly into bearings in stick assembly. Install washer, castellated nut

and cotter pin.

CAUTION

Tighten castellated nut only until there is no axial movement of

bearings and cyclic grip assembly. Overtightening nut will dam-

age bearings.

Install D684-1 spring so that when grip assembly is rotated one turn clockwise, with

co-pilot grip removed, pilot grip (tube) will float just above horizontal and stay full-up

when placed full-up. Install circular plug.

Temporarily attach grip assembly wiring to safety wire (or lacing) exiting atop cyclic

stick. Carefully pull wires thru cyclic stick. Install grommet, included with grip

assembly wiring, into cyclic stick wiring entrance hole. Remove safety wire (or

lacing).

Position protective sleeving on wiring exiting cyclic stick bottom to cover maximum

amount of wiring possible. Secure sleeving ends with lacing tape.

Install pins on each wire into proper position in housings. Refer to Figure 98-2 for

pin positions.

Connect cyclic and airframe wiring and ty-rap. Move cyclic control through all

positions and verify clearance and no binding.

Turn BATTERY switch on and verify correct function of all switches on grip assembly

and cyclic stick.

Install forward belly panel.

25 OCT 2010

Chapter 67 Flight Controls

Page 67.5

67-13 Cyclic Friction Assembly

NOTE

The cyclic friction assembly is located below the forward left

corner of the cyclic box. Turning friction knob clockwise applies

friction to both longitudinal and lateral cyclic axes. Adjustment

is required if friction cannot be applied.

A. Friction Adjustment

1. Turn friction knob counter-clockwise until it stops.

2. Remove roll pin connecting knob to shaft.

3. Lift knob off shaft.

4. Install NAS1149F0432P or NAS1149F0463P washers under knob washer, as

required, so knob rotates 1/8 to 1 turn before adding friction. With friction off, force

at grip to move cyclic shall not exceed 1.75 pounds longitudinal and lateral within

hydraulic servo deadbands.

5. Replace knob and install roll pin.

6. Move flight controls throughout complete travel. Verify no binding.

67-20 Collective Control

67-21 Collective Stick Assembly

A. Removal

1. Refer to Figure 67-1. Disconnect A333-1 collective-travel stop from F348-1 anchor

by removing NAS6603 bolt at bottom of stop. Position stop parallel to collective

stick and apply collective friction.

2. Refer to Figure 6-8. Remove F445-1 forward tunnel cover, F680-3 pilot's collective

cover, F680-1 co-pilot's collective cover, F463-1 mid-tunnel cover, and F461-1

collective cross tube cover.

3. Pivot pilot's seat bottom to the open position. Remove bolt securing inboard end of

collective stick to pilot's seat structure. Refer to Figure 76-1. Disconnect throttle

control inner wire from A462-4 fitting at outboard end of collective. Remove three

screws securing C522-10 throttle control to collective cross tube.

4. Disconnect wiring exiting aft end of center collective stick from airframe harness

connector. Remove ty-raps as required.

5. Disconnect forward end of F121-1 push-pull tube from collective stick assembly.

6. Remove bolt securing outboard end of collective stick to F303-1 support. Remove

two remaining screws securing F303-1 support to cabin. Slide support, with attached

micro-switches, down to allow aft movement of collective stick.

7. Pivot pilot's seat bottom to the open position. Remove bolt securing collective stick

assembly to pilot's seat structure.

8. Carefully move collective stick assembly aft and remove from helicopter.

Page 67.6

Chapter 67 Flight Controls

25 OCT 2010

67-21 Collective Stick Assembly (continued)

Installation

Refer to Figure 67-1. Position A333-1 collective-travel stop parallel to collective

stick and apply collective friction. From aft side of co-pilot's seat, carefully position

collective stick assembly in helicopter.

Pivot pilot's seat bottom to the open position. Install bolt from inside pilot's seat

structure thru bearing block into tunnel and secure to inboard end of collective stick

assembly. Standard torque bolt, install palnut, and torque stripe per Figure 5-1.

At outboard end of collective stick, slide F303-1 support, and attached micro-

switches, up behind collective cross tube and secure support to cabin with two

screws.

Install journal in outboard pivot bearing of collective stick assembly. Position journal

& bearing between flanges of F303-1 support and insert NAS6604 bolt. Standard

torque bolt per Section 20-32, install palnut, and torque stripe per Figure 5-1.

Connect forward end of F121-1 push-pull tube to collective stick assembly with

NAS6604 bolt head on outboard (right) side (nut side inboard). Standard torque bolt

per Section 20-32, install palnut, and torque stripe per Figure 5-1.

Refer to Figure 6-8. Slide F680-3 collective cover over center collective stick aft of

friction assembly.

Insert A130-4 spacer into lower end of A333-1 collective-travel stop. Position spacer

and stop in F348-1 anchor. Install NAS1149F0432P and 0463P washers on spacer

on either side of stop as required to obtain 0.001/0.035 inch axial play and align

stop with collective. Secure stop to anchor with NAS6603 bolt, standard torque per

Section 20-32, install palnut, and torque stripe per Figure 5-1. Move collective up &

down and verify no binding of stop.

CAUTION

NAS6604-9 bolt connecting forward end of F121-1 push-pull tube

to collective must be installed so bolt head is toward right side of

helicopter. Refer to Figure 67-1.

Connect wiring exiting center collective stick to airframe wire harness connector.

Secure connector to airframe harness with Ty-raps as required. Move collective up

& down and verify wiring clearance with no strain.

Refer to Figure 76-1. Secure C522-10 throttle control to collective cross tube with

three clamps and screws. Position control inner wire in A462-4 fitting and rig per

Section 76-11.

10.

Refer to Figure 6-8. Install and secure F445-1 forward tunnel cover, F680-3 pilot's

collective cover, F680-1 co-pilot's collective cover, F463-1 mid-tunnel cover, and

F461-1 collective cross tube cover.

11.

Adjust collective friction per Section 67-22.

25 OCT 2010

Chapter 67 Flight Controls

Page 67.7

67-22 Collective Friction

1. Loosen small screw on collective friction lever.

2. Hold friction lever knob fully aft against collective stick. Adjust screw large screw thru

A333-1 stop to produce a force of 18-22 pounds at collective grip within hydraulic

servo deadbands, then tighten small screw on friction lever screw.

67-30 Jackshaft and Strut Assembly

67-31 Jackshaft

A. Removal

NOTE

Rigging check is not necessary if jackshaft support rod end and

push-pull tube lengths are not altered.

1. Disconnect push-pull tubes from F339-1 jackshaft.

2. Disconnect two bolts connecting jackshaft to G201-1 frame.

3. Remove jackshaft.

Installation

1. Ensure A105-6 journal is installed in jackshaft aft support on G201-1 frame. Position

F339-1 jackshaft on G201-1 frame and install bolts. Standard torque bolts per

Section 20-32, install palnuts, and torque stripe per Figure 5-1.

2. Insert bolt forward thru forward jackshaft arm and connect to upper end of F121-7

push-pull tube. Install A115-1 spacer, A214-3 washer and nut. Standard torque

bolt per Section 20-32, install palnut, and torque stripe per Figure 5-1.

3. Insert bolt aft thru aft jackshaft arm and connect to lower rod end on C343-8 tube.

Install A115-1 spacer, A214-3 washer and nut. Standard torque bolt per Section

20-32, install palnut, and torque stripe per Figure 5-1.

4. Verify no binding and/no interference with control system exists throughout flight

control travel.

Page 67.8

Chapter 67 Flight Controls

25 OCT 2010

67-40 Swashplate

A. Removal

NOTE

Rigging check is not required if push-pull tube rod end center-

to-center dimension does not change.

1. Remove main rotor blades and hub per Sections 62-10 and 62-20.

2. Atop of C251 main rotor drive shaft, remove D226 brackets, D151 teeter stops, and

C150 droop stops by removing NAS6608 bolt.

3. Disconnect upper C204 arm from C203 yokes.

4. Disconnect and remove C203 yokes, A210 key, and chord arm weights.

5. Remove swashplate boot by cutting plastic ty-raps.

6. Disconnect three push-pull tubes and A205 fork assembly from lower (non-rotating)

swashplate.

7. Lift swashplate with attached fork and pitch links off slider tube and remove from

helicopter.

Installation

1. Install swashplate onto slider tube assembly. Connect lower scissors’ fork to left side

of middle of three lugs on lower, non-rotating swashplate. Connect aft push-pull tube

to right side of aft, single lug on lower swashplate. Standard torque bolts per Section

20-32. Install palnuts and special torque per Section 20-33.

2. Verify swashplate tilting friction per Section 67-41; adjust as required.

3. Slide swashplate boot over main rotor drive shaft and set in place.

4. Refer to Figures 8-13 and 8-13A. Install C203 yokes on C251 main rotor drive shaft upper

flange using A210 key to index yokes to shaft. Finger tighten clamping hardware.

NOTE

Round edge of A210 key to fit into drive shaft flange indexing slot.

5. Standard torque NAS6605 bolt thru yokes and A210 key first per Section 20-32. Install

palnuts and special torque per Section 20-33.

6. Standard torque bolt thru yokes opposite A210 key per 20-32. A slight gap between

yokes opposite A210 key is normal.

7. Install previously removed chord arm weights and standard torque bolt per Section 20-

32. Install palnut, special torque per Section 20-33, and torque stripe per Figure 5-1.

25 OCT 2010

Chapter 67 Flight Controls

Page 67.9

67-40 Swashplate (continued)

B. Installation (continued)

If required, fill remainder of rod end threaded hole in upper A205 fork with B270-4 or

-13 sealant (see Section 20-70).

With bolt heads in direction of rotation, connect upper A205 fork to upper C204 arm

and connect arm to C203 yokes. Standard torque bolts per Section 20.32. Verify

0.001/0.005 inch axial play in both pivots; adjust C117 shim thickness between nut-

side journal & thrust washer as required. Verify bolt, arm, and clamped hardware in

upper scissor’s pivots rotate together. Install palnuts , special torque per Section 20-

33, and torque stripe per Figure 5-1.

10.

Verify bolt, arm, and clamped hardware in lower scissor’s pivots rotate together.

Connect forward push-pull tube rod ends to remaining lower lugs on swashplate and

standard torque bolts per Section 20-32. Install palnut, special torque per Section 20-

33, and torque stripe per Figure 5-1.

11.

Connect upper A205 fork rod end and lower rod end of C258 pitch link to interrupter-

side swashplate ear and standard torque bolt per Section 20-32. Install palnut, special

torque per Section 20-33, and torque stripe per Figure 5-1.

12.

Position swashplate boot on rotating swashplate with inner lip contacting C203 yoke.

Secure with ty-raps.

13.

Attach two A255-3 counterweights and lower rod end of C258 pitch link to swashplate

ear opposite interrupter and standard torque bolt per Section 20-32. Install palnut,

special torque per Section 20-33, and torque stripe per Figure 5-1.

14.

Install main rotor hub and blades per Sections

62-10 and 62-20.

15.

Verify safety washers (or counterweight) and C115 spacers installed on all rod ends per

Figure 5-1. Torque stripe fasteners per Figure 5-1.

16.

Verify no interference with control movement throughout flight control travel and

swashplate movement corresponds with cyclic and collective movement.

17.

Track and balance main rotor per Section 18-10.

Page 67.10

Chapter 67 Flight Controls

25 OCT 2010

67-41 Swashplate Tilting Friction Adjustment

Swashplate tilting friction is established by C197-1 through C197-6 shims controlling

clamping force of Teflon®-lined sleeves on the ball assembly.

Mark for reassembly and disconnect boot, pitch links and drive linkage (scissors) from

upper swashplate and both forward push-pull tubes from lower swashplate.

Align upper swashplate arms with lateral axis of helicopter and center cyclic stick. Using

MT359-1 spring scale (or equivalent) connected to upper swashplate arm bolt hole,

pull down and note scale reading while swashplate is moving; do not use breakaway

reading. Force required to tilt swashplate must be free-without-looseness minimum to

5 pounds maximum.

To adjust friction, remove outer screws from upper swashplate and raise and secure

retainers to allow access to inner screws on lower, non-rotating swashplate. Remove

inner screws securing sleeve to lower swashplate.

Raise sleeve and measure thickness of C197 shim stack. Adjust shim stack thickness

as required to achieve proper tilting friction. Decreasing shim stack thickness increases

tilting friction while increasing spacer stack thickness decreases tilting friction. Install,

and special torque per Section 20-33, all inner screws on lower swashplate and at least

two screws thru retainers in upper swashplate prior to measuring tilting friction.

Connect both forward push-pull tubes to lower swashplate and standard torque per

Section 20-32. Install palnut, special torque per Section 20-33, and torque stripe per

Figure 5-1.

Connect both pitch links and drive linkage to upper swashplate (interrupter on same side

as drive linkage) and standard torque per Section 20-32. Install palnuts, special torque

per Section 20-33, and torque stripe per Figure 5-1.

67-42 Upper and Lower Scissor Assemblies

A. Bearing Removal

C648-2 journal bearings may be removed with a press. Press from inner side of bearings

while supporting outboard side of yoke or fork. Use a socket or other suitable pressing

tool to apply the force.

B. Bearing Installation

1. Clean mating surfaces of A205 fork or C203 yoke where C648 bearing is installed.

Deburr any sharp edges that may damage bearings during installation.

2. Coat yoke or fork bearing bores with zinc chromate or epoxy primer. While primer

is still wet, press in C648-2 bearing while supporting backside of fork or yoke.

MAR 2012

Chapter 67 Flight Controls

Page 67.11

67-50 Hydraulic System

WARNING

Except as instructed in this manual, service on the hydraulic

system is limited to component removal and replacement.

CAUTION

Cleanliness of hydraulic fluid is vital to proper system

operation. Use only clean fluid from sealed containers and

avoid contamination from dirty funnels, tubing, etc. Use LPS

PreSolve to clean hydraulic parts. Do not use alcohol.

Hydraulically boosted main rotor flight controls eliminate cyclic and collective feedback forces.

The hydraulic system consists of a pump, three servos, a reservoir, and interconnecting lines.

Normal operating pressure is 450 to 500 psi. The pump is mounted on and driven by the main

rotor gearbox. A servo is connected to each of the three push-pull tubes that support the

main rotor swashplate. The reservoir is mounted to the aft end of the main rotor gearbox and

includes a filter, pressure relief valve, and pilot-controlled pressure shut-off valve.

A sight glass for pre-flight fluid level checks is incorporated in the reservoir and accessible via a

left side cowl door. A vented filler cap is located on top of the reservoir.

The pressure shut-off valve is solenoid-actuated and controlled by the hydraulic switch on the

pilot's cyclic. The switch should be left on during helicopter shutdown and start up except during

the hydraulic system check.

Electrical power is required to turn off hydraulics. Pulling HYD circuit breaker will NOT turn off

hydraulics but will disable hydraulic switch.

67-51 Hydraulic Pump

A. Removal

1. Remove tailcone cowling per Section 53-23.

2. Remove hydraulic reservoir filler-vent and temporarily install an air-tight plug.

3. Refer to Figure 12-4. Remove F902 suction line assembly and protect exposed line

and fitting openings.

4. Remove F902 pressure line assembly and protect exposed line and fitting openings.

5. Remove aft jam nut from both MR rpm senders and remove both senders from

bracket attached to hydraulic pump. Temporarily secure senders away from drive

train to prevent damage.

6. Remove four self-locking nuts and washers securing pump to gearbox and remove

pump and o-ring. Discard o-ring. Protect pump opening on gearbox.

MAR 2012

Chapter 67 Flight Controls

Page 67.13

67-51 Hydraulic Pump (continued)

B. Installation

1. Prelubricate new o-ring with gearbox oil and install on pump mounting flange. With

pump bracket pointing down, install pump on gearbox and secure. Special torque

nuts per Section 20-33.

2. Install both MR rpm senders in pump bracket. Adjust clearance between both senders

and both yoke magnets to 0.040/0.020 inch and hand-tighten sender jam nuts.

3. Refer to Figure 12-4. Install F902 pressure line assembly and special torque per

Section 20-33.

4. Install F902 suction line assembly and special torque per Section 20-33.

5. Remove temporary air-tight plug from reservoir and adjust fluid level as required.

Install filler-vent and special torque per Section 20-33.

6. Torque stripe jam nuts and B-nuts.

7. Bleed hydraulic system per Section 12-34.

8. Install a 110-4 Telatemp on aft surface of pump.

9. Install tailcone cowling per Section 53-23.

67-52 Hydraulic Reservoir

A. Removal

1. Temporarily install a "DO NOT MOVE FLIGHT CONTROLS" sign in cockpit.

2. Remove tailcone cowling per Section 53-23.

3. Place a one-liter container beneath suction tee fitting on reservoir. Remove cap from

tee fitting and allow reservoir fluid to drain into container. Reinstall cap and special

torque per Section 20-33.

4. Remove suction and pressure lines, and disconnect & cap servo supply & return

hoses, from reservoir. Protect line and fitting openings.

5. Disconnect pump bypass solenoid and sight gage LED electrical connectors.

6. Remove three screws securing reservoir to gearbox and remove reservoir.

7. Note alignment of tee fittings and sight gage LED. Transfer LED and line and hose

fittings from removed reservoir to replacement reservoir.

Page 67.14

Chapter 67 Flight Controls

MAR 2012

67-52 Hydraulic Reservoir (continued)

B. Installation

1. Note alignment of tee fittings and sight gage LED on removed reservoir. Transfer

LED and line and hose fittings from removed reservoir to replacement reservoir.

Special torque fittings per Section 20-33.

2. Install reservoir on gearbox and secure with three screws.

3. Install pressure and suction lines, repositioning tee fittings as required, and special

torque per Section 20-33.

4. Connect servo supply and return hoses to reservoir. Position hose elbows to minimize

preload and special torque per Section 20-33.

5. Connect pump bypass solenoid and sight gage LED electrical connectors and ty-rap

wires as required.

6. Fill reservoir with A257-15 hydraulic fluid and special torque filler vent per Section

20-33.

7. Bleed hydraulic system per Section 12-34.

8. Install tailcone cowling per Section 53-23.

MAR 2012

Chapter 67 Flight Controls

Page 67.15

67-53 Hydraulic Servos

A. Servo Removal

CAUTION

Do not pressurize hydraulic system while any hydraulic system

component is disconnected or removed.

Remove mast fairing per Section 53-22. Remove tailcone cowling per Section 53-23.

Refer to Figures 67-2 and 67-3B. Perform the following measurements on all D212

hydraulic servo assemblies to be removed:

a. Measure & record dimension between D200-1 clevis hole center & top of servo

piston.

b. Apply cyclic and collective frictions. With collective full down and hydraulics

unpressurized, position cyclic stick so piston in servo to be removed is in its

lowest position. Measure & record dimension between top of servo piston and

top of cylinder assembly.

Remove hardware securing servo clevis to F121-3 push-pull tube’s lower rod end.

a. Forward Servo: Remove hardware securing servo to F121-5 push-pull tube’s

upper rod end. Remove hardware joining D200-2 scissors.

b. Aft Servo: Remove hardware securing C343-8 tube’s lower rod end to F339-1

jackshaft weldment.

Disconnect D205 hose assemblies from servo unions and tees. Cap and plug fittings.

Remove hardware securing servo to G201-1 frame weldment and remove servo.

Aft Servo: Measure & record center-to-center dimension between aft servo’s lower

rod end and C343-8 tube’s lower rod end. Loosen palnut and nut securing C343-8

tube to aft servo’s lower rod end and remove tube.

CAUTION

Do not remove tri-wing fastener; aft servo’s lower rod end must

remain attached to servo.

CAUTION

Dimension between clevis hole center and top of servo piston

must be 1.40 ± 0.03 inches; dimension between top of servo

piston and top of cylinder assembly must be 0.28 ± 0.03 inch;

dimension between C343-8 tube’s rod ends must be 4.00 ± 0.03

inches. If dimension(s) are not within required range, perform

main rotor rigging per Section 18-40 after servo installation.

Remove clevis, scissor, D200-3 washer, unions, and tee fittings from servo, as

applicable.

Actuate servo piston by hand and drain as much hydraulic fluid from servo as possible.

Plug servo ports.

MAR 2012

Chapter 67 Flight Controls

Page 67.15B

67-53 Hydraulic Servos (continued)

Servo Installation

CAUTION

Do not pressurize hydraulic system while any hydraulic system

component is disconnected or removed.

CAUTION

Refer to Part A. Dimension between clevis hole center and top

of servo piston must be 1.40 ± 0.03 inches; dimension between

top of servo piston and top of cylinder assembly must be 0.28

± 0.03 inch; dimension between C343-8 tube’s rod ends must

be 4.00 ± 0.03 inches. If dimension(s) recorded during servo

removal were not within required range, or if dimension(s) are

unknown, adjust to correct dimensions in Part B steps 1 and 2,

proceed with servo installation thru step 10, then perform main

rotor rigging per Section 18-40.

Refer to Figures 67-2 and 67-3B. Lightly coat D200-1 clevis threads with B270-21

protectant. Assemble clevis, palnut, nut, D200-3 washer (forward servo), and D200-2

scissor (forward servo), and install assembly in D212 hydraulic servo assembly piston.

Adjust dimension between clevis hole center & top of servo piston to dimension

recorded during servo removal, then tighten jam nut and palnut finger tight.

Aft Servo: Lightly coat servo’s lower rod end threads with B270-21 protectant and

install C343-8 tube. Adjust tube on servo‘s rod end, and tube’s rod end, to the

center-to-center dimension (between rod ends) recorded during servo removal, and

with rod ends 90° to each other. Tighten jam nuts and palnuts finger tight.

CAUTION

Do not remove tri-wing fastener; aft servo’s lower rod end must

remain attached to servo.

Install hardware securing servo to G201-1 frame weldment. Standard torque

fasteners per Section 20-32 and torque stripe per Figure 5-1.

Forward Servos: Install hardware joining scissors (scissor overlap direction not

critical); special torque nut to 25 in.-lb, special torque palnut to 5-10 in.-lb, and

torque stripe per Figure 5-1.

Using backup wrench, align clevis parallel with helicopter’s longitudinal axis, standard

torque jam nut and palnut per Section 20-32, and torque stripe per Figure 5-1.

Install hardware securing servo clevis to F121-3 push-pull tube’s lower rod end.

Standard torque fastener per Section 20-32 and torque stripe per Figure 5-1.

a. Forward Servo: Install hardware securing servo to F121-5 push-pull tube’s upper rod

end. Standard torque fastener per Section 20-32 and torque stripe per Figure 5-1.

b. Aft Servo: Install hardware securing C343-8 tube’s lower rod end to F339-1

jackshaft weldment. Standard torque fastener per Section 20-32 and torque stripe

per Figure 5-1. Using backup wrench, standard torque jam nuts and palnuts, and

torque stripe per Figure 5-1.

Page 67.16

Chapter 67 Flight Controls

MAR 2012

67-53 Hydraulic Servos (continued)

B. Servo Installation (continued)

Refer to Figure 5-2. Verify proper rod end centering on all push-pull tubes attached

to servos.

Remove caps and plugs. Lubricate new packings using A257-15 hydraulic fluid and

install packings on servo unions and tees. Install fittings with associated hardware in

servo ports and connect D205 hose assemblies to fittings. Align fittings to minimize

hose preload and ensure hose clearance with surrounding structure; special torque

fittings per Section 20-33 and torque stripe per Figure 5-1. Special torque hose

B-nuts per Section 20-33 and torque stripe per Figure 5-1.

10.

Bleed hydraulic system per Section 12-34.

11.

Perform the following measurements on all servos just installed:

a. Measure & record dimension between clevis hole center & top of servo piston.

b. Apply cyclic and collective frictions. With collective full down and hydraulics

unpressurized, position cyclic stick so piston in servo just installed is in its lowest

position. Measure & record dimension between top of servo piston and top of

cylinder assembly.

CAUTION

Dimension between clevis hole center and top of servo piston

must be 1.40 ± 0.03 inches; dimension between top of servo

piston and top of cylinder assembly must be 0.28 ± 0.03 inch;

dimension between C343-8 tube’s rod ends must be 4.00 ±

0.03 inches. If dimension(s) recorded are not within required

range, adjust to correct dimensions in Part B steps 1 and 2,

proceed with servo installation thru step 10, then perform main

rotor rigging per Section 18-40.

12.

Install tailcone cowling per Section 53-23. Install mast fairing per Section 53-22.

MAR 2012

Chapter 67 Flight Controls

Page 67.17

67-60 Tail Rotor Controls

67-61 Pedals

A. Removal

Soak both front floor carpets with Prep-sol for 15-20 minutes, then lift carpet

carefully from the floor on both sides and remove from the cabin. Caution: This is a

flammable material. Follow manufacturer’s safety precautions to prevent injury.

Refer to Figure 67-4. Remove the screws between the pedals holding the access

plates to the floor and remove the plates.

Remove screws securing upper console and pivot console up and aft.

Disconnect both pedal assemblies from the C343-9 & -11 push-pull tubes.

CAUTION

DO NOT remove the rod ends or change the length of the push-

pull tubes.

Remove six NAS6603-20 bolts (three per side) which hold the A318-1 and -2 bearing

block halves together.

Remove the lower bearing block halves.

Remove the tail rotor pedals one at a time by lifting one end and lowering other into

chin. Remove pedals thru pilot-side opening.

NOTE

On reassembly, the right pedal assembly is mounted forward in

the bearing blocks and the left is mounted aft.

NOTE

Pedal blocks (upper and lower) are a machined matched set as

indicated by matching letter or number on the upper and lower

portion of blocks. DO NOT mix them or alignment problems

may develop on installation.

25 OCT 2010

Chapter 67 Flight Controls

Page 67.19

67-61 Pedals (continued)

B. Installation

1. Fill the grooves in the pedal bearing blocks with A257-1 grease.

2. Install the pedal assemblies into the bearing blocks and torque the bearing block

attach bolts per Section 20-32.

NOTE

If a force greater than 5 lbs is required to move pedals, check

the bearing blocks to ensure they are matched correctly.

3. Connect both pedal assemblies to the push-pull tubes and torque the NAS6604-9

bolts to per Section 20-32 and install palnuts.

4. Move the pedals through the full range of travel to ensure there is no interference or

binding.

5. Secure console. Install the pedal cover plates and carpeting. Use B270-7 or -8

adhesive to attach carpeting.

67-62 Pitch Control

A. Removal

1. Remove tail rotor assembly per Section 64-11. Mark corresponding tail rotor blade

grips, tail rotor pitch change to each of the pitch control ears, for later reinstallation

so re-rigging is not required.

2. Disconnect and remove A120-5 aft bellcrank per Section 67-75.

3. Remove C031-1 pitch control from tail rotor output shaft. Clean output shaft.

Installation

1. Verify inner bore of C031-1 pitch control is clean. Slide pitch control assembly onto

clean output shaft.

2. With pitch control's input stud thru short arm of A120-5 bellcrank assembly, position

bellcrank on tail rotor gearbox and install NAS6604-25 bolt, one AN960-416L

washer under bolt head, two MS20002-4 washers, one on each side of bearing and

MS21042-L4 nut. Tighten but don’t torque at this time.

3. Measure vertical gap between A120-5 bellcrank arm and flange on pitch control

stud. Install sufficient C117-34, - 35 and -36 washers between bellcrank and stud to

fill gap within ± 0.003 inch. Install one NAS1149F0432P washer and MS21042-L5

nut on protruding end of stud. Torque nut to 200 in.-lb plus nut drag while holding

stud from rotating. Install palnut and special torque per Section 20-33.

4. Standard torque bolt thru A120-5 bellcrank pivot per Section 20-32 and install palnut

and special torque per Section 20-33.

5. Attach aft end of C121-17 push-pull tube to A120-5 bellcrank and standard torque

bolt per Section 20-32.

6. Install hardware securing pitch links, standard torque bolts and palnuts per Section

20-32, and torque stripe per Figure 5-1.

7. Install tail rotor assembly per Section 64-10.

Page 67.20

Chapter 67 Flight Controls

25 OCT 2010

67-70 Bellcranks

67-71 C317-5 Bellcrank

A. Removal

1. Remove two screws securing the upper console. Lift up console and disconnect

outside air temperature gage wiring.

2. Remove radios, radio panel face plate, and radio rack which is secured with screws

to the side panels.

3. Refer to Figure 67-4. Disconnect forward C343-11 and C343-13 push-pull tubes

and push-pull tube from the bellcrank by removing three NAS6604-9 bolts.

4. Remove four screws securing F349-1 support weldment to cabin and remove support

and attached bellcrank.

5. Remove NAS6604-19 bolt which connects the bellcrank to the support. Remove

bellcrank.

Installation

This procedure also covers rigging of the lower push-pull tubes and pedal assemblies.

Rigging is required if any push-pull tube length changed. If rigging is not required,

disregard rigging portions and follow installation sequences.

1. Install two A105-3 journals inside C317-5 bellcrank. Place one A141-3 washer

both outboard faces of A105-3 journals and secure to F349-1 support weldment.

Standard torque bolt per Section 20-32. Install palnut and special torque per Section

20-33.

2. Install support assembly in helicopter and secure with four MS27039C0807

screws.

3. C343-11 push-pull tube's rod end center-to-center dimension to 6.00 inches and

connect it to the C317-5 bellcrank.

4. Adjust C343-13 push-pull tube's rod end center-to-center dimension to 5.30 inches

and connect it to the C317-5 bellcrank.

5. Ensure F121-9 push-pull tube is installed through the center of the C346-1 restraint

at the mid span position. Connect forward end of F121-9 push-pull tube to C317-5

bellcrank.

6. Install a 3/16-inch diameter pin through the rigging hole located in the right aft

passenger cargo compartment and push it through C317-7 bellcrank's rigging hole.

With rigging pin installed, adjust length of F121-9 push-pull tube to achieve 5.24

inches dimension shown in Figure 67-4. Verify proper rod end thread engagement.

Remove rigging pin and standard torque bolt per Section 20-32. Install palnut,

special torque per Section 20-33, and torque stripe per Figure 5-1.

7. Move pedals full travel. Verify easy, smooth movement with no interference between

tubes, wires and structure.

8. Install radio rack, radio face plate, and radios. Connect outside air temperature gage

wiring.

9. Close and secure upper console.

25 OCT 2010

Chapter 67 Flight Controls

Page 67.21

67-72 C317-7 Bellcrank

A. Removal

1. Refer to Section 6-70. Remove F794-2 aft belly cover, F932-1 middle seat backrest

assembly, and F474-2 middle seat cover.

2. Disconnect F121-9 and F121-11 push-pull tubes from the C317-7 bellcrank.

3. Remove nuts and accompanying washers securing NAS6604-67 bolt in F334-1

support assembly. Withdraw bolt sufficient to remove C317-7 bellcrank and remove

bellcrank, two A141-3 washers, and two A105-3 journals.

Installation

1. Install two A105-3 journals in C317-7 bellcrank's pivot bearing bore. With 3/16 inch

rigging pin hole aft and an A141-3 washer against outboard face of each journal,

install bellcrank on F334-1 support assembly and retain with NAS6604-67 bolt.

2. Install two NAS1149F0463P and one NAS1149F0432P washer followed by

MS21042L4 nut on NAS6604-67 bolt. Standard torque bolt per Section 20-32.

Install palnut, special torque per Section 20-33, and torque stripe per Figure 5-1.

3. Connect F121-9 push-pull tube assembly to C317-7 bellcrank and standard torque

bolt per Section 20-32. Install palnut, special torque per Section 30-33, and torque

stripe per Figure 5-1.

4. Move pedals full travel. Verify smooth movement and no interference.

5. Install F794-2 aft belly cover, F932-1 middle seat backrest assembly, and F474-2

middle seat cover.

67-73 F316-1 Bellcrank

A. Removal

1. Remove main rotor gearbox per Section 63-20.

2. Disconnect F121-11 push-pull tube from F316-1 bellcrank assembly.

3. Disconnect F121-13 push-pull tube from F316-1 bellcrank assembly.

4. Remove nuts and spacer from outboard end of C494-2 shaft. Move shaft slightly

inboard and remove washer from between frame tab and bellcrank.

5. Remove spring pin, castellated nut, and washers from inboard end of C494-2 shaft.

Move shaft slightly outboard and remove washer from between bellcrank and inboard

support.

6. Remove bellcrank.

Page 67.22

Chapter 67 Flight Controls

25 OCT 2010

67-73 F316-1 Bellcrank (continued)

Installation

1. Install one A141-3 washer on C494-2 shaft adjacent to both inboard and outboard

end of F316-1 bellcrank.

2. Install bellcrank with washers in helicopter with longer arm pointing up.

3. On inboard end of C494-2 shaft, install two NAS1149F0463P washers followed by

MS17825-4 castellated nut. Tighten nut until it aligns with hole in shaft and install

new MS16562-14 spring pin.

4. On outboard end of shaft install C130-34 spacer and MS21042L4 nut. Special

torque nut to 90 in.-lb. Install palnut and special torque per Section 20-33. Torque

stripe inboard and outboard nuts per Figure 5-1.

5. Connect F121-13 push-pull tube to bellcrank and standard torque bolt per Section

20-32. Install palnut, special torque per Section 20-33, and torque stripe per Figure

5-1.

6. Connect F121-11 push-pull tube to bellcrank and standard torque bolt per Section

20-32. Install palnut, special torque per Section 20-33, and torque stripe per Figure

5-1.

7. Move pedal full travel. Verify smooth movement and no interference.

8. Install main rotor gearbox per Section 63-20.

67-74 A331-4 Bellcrank

A. Removal

1. Disconnect F121-13 and C121-17 push-pull tubes from A331-4 bellcrank.

2. Disconnect NAS6604-35 attach bolt and remove bellcrank and two A105-3

journals.

B. Installation

1. Install two A105-3 journals in C331-4 bellcrank's pivot bearings. Install an

NAS1149F0432P washer under head of an NAS6604-35 bolt followed by an A141-

3 washer and insert bolt thru journals. Install an A141-3 washer on bolt against

journal face, followed by an NAS1149F0432P washer.

2. Install bellcrank, with straight side aft, on F020-1 frame's boss, and secure to frame

with an NAS1149F0432P washer and MS21042L4 nut. Standard torque bolt per

Section 20-32. Install palnut, special torque per Section 20-33, and torque stripe

per Figure 5-1.

25 OCT 2010

Chapter 67 Flight Controls

Page 67.23

CHAPTER 71

POWERPLANT

71-00 Description

One Rolls-Royce model 250-C300/A1 (commercial designation RR300) free-turbine turboshaft

engine powers the helicopter. The engine is equipped with an ignition exciter, igniter, starter-

generator, two tachometer senders, and additional powerplant instrument senders.

A direct drive, squirrel cage style cooling fan is mounted to the intermediate shaft and supplies

cooling air to the engine and gearbox oil coolers.

Induction air enters through multiple openings in the upper fuselage cowlings and flows into

a plenum forward of the firewall. The plenum contains a radial-flow air filter at the engine

compressor inlet.

If the air filter becomes blocked, spring-loaded doors at the front of the filter housing open

allowing unfiltered air to the engine. The AIR FILTER annunciator illuminates when filter

bypass is occurring.

Periodically performing power assurance checks may provide indication of engine deterioration

or air filter blockage. Maintenance actions such as air filter cleaning and compressor wash

should be performed if aircraft fails power assurance check.

A temperature switch is mounted to the firewall above the engine to detect a fire in the

engine compartment. Abnormally high temperature causes the ENGINE FIRE annunciator to

illuminate.

Chapter 71 Powerplant

Page 71.1

71-10 Engine

Refer to R66 Illustrated Parts Catalog (IPC) Chapter 71.

NOTE

The electronic monitoring unit (EMU) is a serialized component

assigned to the engine. When removing the engine, remove the

engine's EMU per Section 71-43, as required.

A. Removal

Remove engine cowling assembly per Section 53-21.

Refer to Figures 71-1 and 71-2. Verify heat shrink stamping is legible (or mark wires

and cables) and remove hardware securing wires and cables to starter-generator studs.

Disconnect F059-01 (cabin) electrical harness from F049-02 (engine) harness at F577-1

bracket assembly. Disconnect cabin harness "TMP" (torquemeter oil pressure) and

"MOP" (main oil pressure) plugs from engine sensors; disconnect cabin harness plug

from N2 speed sensor.

Pull fuel shut off valve OFF. Disconnect B283-12 (fuel) hose assembly B-nut from

engine fuel inlet fitting. Cap fitting and plug line.

Remove hardware securing MS21919WDG36 clamp to firewall, and loosen B277-

32 clamps securing A785-37 hose to inducer bleed port and G918-1 box assembly.

Remove hose and clamps. Install cover on inducer bleed port and tape box assembly to

protect openings from contaminants.

Remove hardware securing G391-1 (customer air) line assembly clamps. Loosen line

assembly B-nut from G391-5 line assembly union and disconnect B-nut from engine

compressor union. Cap fitting and plug line.

Drain engine oil per Section 12-60; drain engine oil per RR300 Operation and Maintenance

Manual (OMM). Refer to Figure 79-2. Remove hardware securing F723 oil line assembly

clamps. Loosen F723-1, F723-2, and F723-3 line assembly B-nuts from F649-1 oil cooler

and G689-1 oil tank assembly unions; disconnect B-nuts from engine fittings. Cap fittings

and plug lines.

Refer to Figure 63-1. Remove hardware securing F018-1 clutch assembly yoke to (aft)

A947-2 plate assembly, noting hardware removed.

Refer to Figure 76-1. Remove fasteners securing C522-10 (throttle) and A522-10 (fuel

cutoff) control inner wires to FCU throttle and fuel cutoff levers. Remove fasteners securing

control housings and AN742-4 clamps to F577 bracket assemblies. Refer to Figure 76-2.

Remove cotter pin and washer securing C522-11 (power turbine governor) control inner

sleeve and D333-13 fitting to PTG input lever; disconnect control from lever.

Remove exhaust per Section 71-30.

10.

Connect engine hoist to G200-1 engine lifting lug. Support engine during mounting

hardware removal.

11.

Cut and discard safety wire and remove two bolts securing bottom engine mount to

F174-1 support weldment. Cut and discard safety wire and remove two bolts (one per

side) securing side engine mounts to F046 lower frames.

12.

Carefully remove engine; verify F579-1 bellmouth is clear of firewall, and loose wires, cables,

fittings and line assemblies are clear of engine during separation. Install bellmouth cover.

13.

Prepare engine for Rolls-Royce maintenance facility per Section 71-11, as required.

Chapter 71 Powerplant

Page 71.3

71-10 Engine (continued)

Installation

Prepare engine for installation in helicopter per Section 71-12, as required.

Refer to Figures 71-1 and 71-2. Connect engine hoist to G200-1 engine lifting lug.

Remove F579-1 bellmouth cover. Carefully install engine, inserting bellmouth through

firewall. Do not pinch loose wires or cables, or damage fittings or line assemblies. Before

installing engine mounting hardware, verify the inlet seal is centered when pressed

against the firewall, and that the seal is not twisted or pinched.

Install hardware securing side engine mounts to F046 frames. Standard torque bolts

(one per side) per Section 20-32; install 0.032-inch diameter lockwire and safety bolts

to frames. Install hardware securing bottom engine mount to F714-1 support weldment.

Special torque bolts per Section 20-33; install 0.032-inch diameter lockwire and safety

three bolts together. Remove engine hoist.

Install exhaust per Section 71-30.

Refer to Figure 63-1. Install hardware securing F018-1 clutch assembly yoke to (aft)

A947-2 plate assembly, as removed. Perform engine driveline shimming per Section

63-11. Standard torque nuts and palnuts per Section 20-32, and torque stripe per

Figure 5-1. Verify 0.2 inch minimum clearance between shaft weldment and firewall

grommet; verify equal gap concentrically between shaft and box assembly hole edges.

Adjust F174-1 support weldment rod ends per Section 53-31 as required.

Remove cap and torque check engine compressor (customer air) union per RR300

Operation and Maintenance Manual (OMM). Remove plug and connect G391-1 line

assembly B-nut to engine. Special torque B-nuts per Section 20-33 and torque stripe

fittings. Install hardware securing line assembly clamps.

Refer to Figure 79-2. Remove caps and torque check engine (oil line) fittings per RR300

OMM. Remove plugs and connect F723-1, F723-2, and F723-3 line assembly B-nuts to

engine. Special torque B-nuts at engine, F649-1 oil cooler, and G689-1 oil tank assembly

per Section 20-33, and torque stripe fittings. Install hardware securing line assembly

clamps. Service engine oil per RR300 OMM; service engine oil per Section 12-60.

Remove cover and tape and install B277-32 clamps and A785-37 hose onto inducer

bleed port and G918-1 box assembly; tighten clamps. Install MS21919WDG36 clamp

around hose, and install hardware securing clamp and hose to firewall. Verify security.

10.

Remove cap and torque check engine fuel inlet fitting per RR300 OMM. Remove plug

and connect B283-12 (fuel) hose assembly B-nut to inlet fitting. Special torque B-nut

per Section 20-33 and torque stripe per Figure 5-1. Push fuel shut off valve ON.

11.

Connect F059-01 (cabin) electrical harness plug to N2 speed sensor; connect cabin

harness "TMP" (torquemeter oil pressure) and "MOP" (main oil pressure) plugs to

engine sensors. Connect cabin harness to F049-02 (engine) harness at F577-1 bracket

assembly. Install wires and cables on starter-generator studs according to stamping.

Install hardware, special torque nuts, and torque stripe per Figure 5-1.

12.

Perform FCU throttle and fuel cutoff control rigging per Sections 76-11 and 76-12. Perform

PTG control rigging per Section 76-21 (perform PTG rigging check during run-up).

13.

Install engine EMU per Section 71-60, as required.

14.

Perform ground check per Section 5-41. Remove the air from the engine fuel system,

then perform fuel flow check, per RR300 OMM. Perform run-up per Section 5-42, and

PTG rigging check per Section 76-22.

15.

Install engine cowling assembly per Section 53-21.

Chapter 71 Powerplant

Page 71.5

71-11 Preparing Engine for Rolls-Royce Maintenance Facility

Refer to R66 Illustrated Parts Catalog (IPC) Chapter 71.

NOTE

Cap and plug Rolls-Royce engine model 250-C300/A1 engine

fluid ports, electrical connectors, etc., and in removed

components, progressively during procedure to prevent foreign

object contamination.

Refer to Figures 71-1 and 71-2. Remove hardware securing (2) MS21919WCH14 clamps

to Rolls-Royce engine model 250-C300/A1 engine vertical firewall and F577-5 bracket.

Loosen B277-8 clamp and remove A785-36 hose and F170-1 fitting. Install plug.

Refer to Figure 76-1. Remove F147-1 (minimum throttle stop) screw and D930-2

spring from fuel control unit.

Refer to Figure 71-4. Remove hardware securing F169-2 base and F577-5 bracket to

exhaust collector. Remove base and bracket, and install exhaust collector cover.

To remove F049-09 harness assembly:

a. Disconnect F049-09 harness assembly’s plug from engine magnetic plug on bottom

of engine accessory gearbox.

b. Remove hardware securing harness wire terminal to igniton exiter box stud.

c. Cut and discard ty-raps as required, and disconnect G426-1 (fuel differential

pressure) switch assembly wire from harness at connectors. Cut and discard

stand-off ty-raps at switch wire and F741-1 line assembly.

d. Remove hardware securing (2) MS21919WCH4 clamps to (bottom of) engine gearbox.

e. Disconnect harness plugs from anti-ice valve assembly solenoid, anti-ice pressure

switch assembly, and N₁ speed pick-up assembly.

f. Remove hardware securing (2) MS21919WCH4 clamps to (2) engine-supplied

MS9592-050 brackets.

g. Remove hardware securing harness wire terminals to measured gas temperature

(MGT) thermocouple studs.

h. Disconnect harness plug from engine magnetic plug near oil line unions.

i. Cut and discard ty-raps as required, and disconnect D745-3 pressure switch

assembly from harness at connectors.

j. Remove hardware securing F577-1 and F577-3 bracket assemblies to (right side

of) engine gearbox. Remove harness.

Remove engine inlet bellmouth per Section 71-23 Part A steps 2 and 3.

Disconnect F741-1 line assembly from G426-1 switch assembly and fuel pmp’s A919-

0D reducer and remove line.

Disconnect F727-1 line assembly from fuel pump’s A919-2D reducer. Disconnect

F727-2 line assembly from engine fireshield’s drain fitting. Remove hardware securing

MS21919WCH4 clamp the combustion section’s plug flange and remove lines.

Page 71.6

Chapter 71 Powerplant

71-11 Preparing Engine for Rolls-Royce Maintenance Facility (continued)

8. Remove A919-0D and A919-2D reducers, and G426-1 switch assembly, from fuel pump.

9. Remove hardware securing F593-3 plate to bottom of engine gearbox and remove plate.

10. Remove hardware securing engine-supplied rear PTO pad cover and remove cover.

Remove bolt, washer, and G732-1 cap securing F018-1 clutch assembly in engine

gearbox and remove clutch assembly.

11. Remove AN815-8D union from engine gearbox TANK VENT port, AN815-8D union or

CV26-77 check valve (early R66s) from OIL OUTLET port, and AN815-10D union from

OIL INLET port. Remove D745-3 pressure switch assembly from engine gearbox.

12. Cut and discard safety wire, remove hardware securing G200-1 mount and G200-2

cover from (top of) engine gearbox, and remove mount and cover. Remove residual

B270-1 sealant.

71-12 Preparing Engine for Helicopter Installation

Refer to R66 Illustrated Parts Catalog (IPC) Chapter 71.

NOTE

Remove protective caps and plugs progressively during procedure

to prevent foreign object contamination.

Refer to Figures 71-1 and 71-2. Position G200-2 cover and G200-1 mount on top of

Rolls-Royce engine model 250-C300/A1 accessory gearbox as shown. Install hardware,

standard torque bolts per Section 20-32, and torque stripe per Figure 5-1. Install 0.032-

inch diameter lockwire and safety bolt heads together. Seal cover edges with B270-1

sealant.

Install D745-3 pressure switch assembly on front of engine gearbox as shown, special

torque switch per Section 20-33, and torque stripe per Figure 5-1.

Install NAS617-10 packing on AN815-10D union and install union in engine gearbox OIL

INLET port. Special torque union per Section 20-33 and torque stripe per Figure 5-1.

CAUTION

Installing CV26-77 check valve incorrectly can destroy oil tank.

Install NAS617-8 packing on AN815-8D union or CV26-77 check valve (early R66s; at

straight thread) and install union or check valve (flow arrow to point away from engine)

in engine gearbox OIL OUTLET port. Special torque union or check valve per Section

20-33 and torque stripe per Figure 5-1.

Install NAS617-8 packing on AN815-8D union and install union in engine gearbox TANK

VENT port. Special torque union per Section 20-33 and torque stripe per Figure 5-1.

Inspect F018-1 clutch assembly splines and verify no evidence of galling. Also, verify

end of thread insert is 0.090 - 0.110 inch inboard from tip of splined end of clutch

housing; contact RHC Technical Support if thread insert position is incorrect. Lubricate

clutch splines using B270-21 protectant. Insert clutch in engine gearbox, and install

G732-1 cap, bolt, and washer at rear PTO pad. Standard torque bolt per Section 20-32

and torque stripe per Figure 5-1.

Chapter 71 Powerplant

Page 71.7

71-12 Preparing Engine for Helicopter Installation (continued)

Install engine-supplied rear PTO pad cover, and engine-supplied nuts and spacers.

Special torque nuts per Section 20-33 and torque stripe per Figure 5-1.

Position F593-3 plate on bottom of engine gearbox and install aft bolt, finger tight.

Install G426-1 switch assembly in fuel pump BF (before filter) port. Special torque

switch per Section 20-33 and torque stripe per Figure 5-1.

10.

Install MS29512-3 packing on A919-0D reducer and install reducer in fuel pump AF (after

filter) port. Special torque reducer per Section 20-33 and torque stripe per Figure 5-1.

11.

Install MS29512-3 packing on A919-2D reducer and install reducer in fuel pump DRAIN

port. Special torque reducer per Section 20-33 and torque stripe per Figure 5-1.

12.

Connect F727-1 line assembly to fuel pump’s A919-2D reducer. Connect F727-2

line assembly to engine fireshield’s drain fitting. Install one MS21919WCH4 clamp

around each line, install hardware securing lines to combustion section’s plug flange,

and tighten screw. Special torque F727-1 line assembly nut at reducer per Section 20-

33 and torque stripe per Figure 5-1; special torque F727-2 line assembly at fireshield’s

drain fitting and torque stripe per Figure 5-1. Verify security.

13.

Connect F741-1 line assembly to G426-1 switch assembly and fuel pump’s A919-0D

reducer. Special torque nuts per Section 20-33 and torque stripe per Figure 5-1.

14.

Install engine inlet bellmouth per Section 71-23 Part B steps 1 & 2. Install bellmouth cover.

15.

To install F049-09 harness assembly:

Position F577-1 bracket assembly on F049-09 harness assembly’s D38999-20FC

connector so connector’s main keyway will face outboard. Install and tighten

hardware; verify security. Install bracket on (right side of) engine gearbox, special

torque nuts per Section 20-33, and torque stripe per Figure 5-1.

Install MS21919WCH8 clamp around harness assembly and install clamp on F577-3

bracket assembly. Install and tighten hardware. Install bracket on (right side of) engine

gearbox, special torque nuts per Section 20-33, and torque stripe per Figure 5-1.

Connect harness to D745-3 pressure switch assembly at connectors. Verify

security. Install (2) MS3367-7-9 ty-raps to secure plug. Cinch ty-raps until snug

without overtightening and trim tips flush with heads.

Connect harness plug to engine magnetic plug near oil line unions. Verify plug

security.

Install harness wire terminals (white-to-white, green-to-green) on measured gas

temperature (MGT) thermocouple studs. Install hardware, special torque nuts per

Section 20-33, and torque stripe per Figure 5-1.

Verify (2) engine-supplied MS9592-050 brackets are installed on engine lube oil

filter assembly per Rolls-Royce SB RR300-72-014. Install (2) MS21919WCH4

clamps around harness assembly and install clamps on brackets. Install and tighten

hardware; verify security.

Connect harness plugs to anti-ice valve assembly solenoid, anti-ice pressure switch

assembly, and N₁ speed pick-up assembly. Verify security.

Page 71.8

Chapter 71 Powerplant

71-12 Preparing Engine for Helicopter Installation (continued)

15. h. Install (2) MS21919WCH4 clamps around harness assembly and install clamps on

(bottom of) engine gearbox. Install hardware, special torque nuts per Section 20-

33, and torque stripe per Figure 5-1.

i. Stand-off ty-rap G426-1 (fuel differential pressure) switch assembly’s wire from

F741-1 line assembly using MS3367-4-9 ty-raps. Connect switch wire to harness

at connectors. Install (2) MS3367-5-9 ty-raps to secure connectors to harness.

Cinch ty-raps until snug without overtightening and trim tips flush with heads.

j. Install harness wire terminal on ignition exiter box stud. Install hardware, special

torque nut per Section 20-33, and torque stripe per Figure 5-1.

k. Connect harness plug to engine magnetic plug on bottom of engine gearbox. Verify

plug security.

16.

Refer to Figure 71-4. Verify F169-2 (exhaust) base and engine exhaust collector

mating surfaces are clean and dry, and lay 0.25 inch bead 7020-3 ceramic putty on

top of exhaust collector flange. Position F169-2 base and F577-5 bracket on exhaust

collector and install hardware. Verify security. Remove excess putty. Install exhaust

protective cover.

17.

Refer to Figure 76-1. Install F147-1 (minimum throttle stop) screw in fuel control

unit, special torque screw per Section 20-33, and torque stripe per Figure 5-1. Install

D930-2 spring.

18.

Install (2) A215-016 o-ring and NAS617-12 packing on F170-1 fitting and install fitting

in engine gearbox OB VENT port. Special torque fitting per Section 20-33 and torque

stripe per Figure 5-1. Position A785-36 hose and B277-8 clamp over fitting and tighten

clamp. Verify security. Position (2) MS21919WCH14 clamps over hose and install

and tighten hardware securing clamps to engine vertical fireshield and F577-5 bracket.

Verify security.

Chapter 71 Powerplant

Page 71.9

71-20 Induction

CAUTION

Never operate engine without G057-1 cage assembly installed.

F771-1 filter assembly not required for flight.

CAUTION

Do not perform maintenance near engine inlet without either a

filter assembly or a temporary cover installed on G057-1 cage

assembly. Contact Rolls-Royce Customer Support if foreign

objects enter inlet.

71-21 Air Filter Assembly

Refer to R66 Illustrated Parts Catalog (IPC) Figure 71-9.

NOTE

Replace F771-1 air filter assembly “on-condition”.

A. Removal

1. Remove tailcone cowling assembly per Section 53-23. Open main rotor gearbox

compartment access door.

2. Refer to Figure 71-3. Vacuum exterior of F771-1 filter assembly.

3. Disconnect F049-08 (air filter switch) electrical harness plug from F059-01 (cabin)

harness at G258-4 strap.

4. Loosen B277-4 clamp securing A729-42 tube to G738-1 nozzle; pull tube off of

nozzle.

5. Pull filter forward off of G057-1 cage assembly.

Installation

1. Refer to Figure 71-3. Pull F771-1 filter assembly aft over G057-1 cage assembly.

2. Install B277-4 clamp and A729-4 tube onto G738-1 nozzle and tighten clamp. Verify

security.

3. Connect F049-08 (air filter switch) electrical harness plug to F059-01 (cabin) harness

at G258-4 strap.

4. Turn BATTERY switch ON. To test air bypass warning circuit, verify annunciator

panel warning segment illuminates when bypass doors are opened individually, then

simultaneously. Turn BATTERY switch OFF.

5. Install tailcone cowling assembly per Section 53-23. Close main rotor gearbox

compartment access door.

6. Perform compressor rinse per RR300 Series Operation and Maintenance Manual (OMM).

Chapter 71 Powerplant

Page 71.11

71-22 Cage Assembly

Refer to R66 Illustrated Parts Catalog (IPC) Figure 71-9.

A. Removal

1. Remove tail rotor drive fan shaft per Section 65-10.

2. Remove air filter assembly per Section 71-21.

3. Refer to Figure 71-3. Remove hardware securing G057-1 cage assembly to firewall

and remove cage. Install suitable barrier to prevent foreign objects from entering

engine inlet.

B. Installation

1. Refer to Figure 71-3. Remove barrier, position G057-1 cage assembly against

firewall, and install hardware securing cage to firewall. Verify security.

2. Install air filter assembly per Section 71-21.

3. Install tail rotor drive fan shaft per Section 65-10.

71-23 Engine Inlet Bellmouth

Refer to R66 Illustrated Parts Catalog (IPC) Figure 71-11.

A. Removal

1. Remove engine per Section 75-10.

2. Refer to Figure 71-3. Remove F579-1 bellmouth cover and loosen B277-36 clamps

securing bellmouth to engine front support. Remove bellmouth and clamps.

3. Remove hardware securing F597-1 seal and F580-1 inlet to engine front support.

Remove seal and inlet. Install cover over front support.

B. Installation

1. Refer to Figure 71-3. Remove engine front support cover, install F580-1 inlet and

F597-1 seal (drain hole on bottom) on front support, and install hardware. Verify

security.

2. Install B277-36 clamps and F579-1 bellmouth over front support flange, and tighten

clamps. Verify security.

3. Install engine per Section 71-10.

Page 71.12

Chapter 71 Powerplant

71-30 Exhaust Weldment

Refer to R66 Illustrated Parts Catalog (IPC) Figure 71-13.

A. Removal

1. Remove engine cowling assembly per Section 53-21.

2. Refer to Figure 71-4. Remove hardware securing F173-1 struts to F169-1 exhaust

weldment and engine, and remove struts.

3. Loosen B277-8 clamp securing A785-36 (accessory gearbox vent) hose to exhaust; pull

hose off of exhaust weldment.

4. Remove three fasteners securing exhaust weldment to engine exhaust collector.

Carefully lift exhaust weldment up and off of F169-2 base flange, and remove exhaust

weldment.

5. As required, remove hardware securing base and F577-5 bracket to exhaust collector

and remove base. Install exhaust collector cover.

Installation

1. Refer to Figure 71-4. If F169-2 base is installed, proceed to step 3. Verify base and

engine exhaust collector mating surfaces are clean and dry, and lay 0.25 inch bead

7020-3 ceramic putty on top of exhaust collector flange.

2. Position F169-2 base and F577-5 bracket on exhaust collector and install hardware.

Verify security. Remove excess putty.

3. Position F169-1 exhaust weldment on base and install three fasteners securing exhaust

weldment to exhaust collector.

4. Install hardware securing F173-1 struts to exhaust weldment and engine. Special torque

engine tee-bolts per Section 20-33.

5. Position A785-36 (accessory gearbox vent) hose with B277-8 clamp over exhaust

weldment vent tube. Orient clamp so clamp’s fitting, and any slight bunching of hose,

is on top of vent tube, and tighten clamp. Verify security.

6. Install engine cowling assembly per Section 53-21.

Chapter 71 Powerplant

Page 71.15

71-40 Accessories

71-41 Starter-Generator

Refer to R66 Illustrated Parts Catalog (IPC) Figure 71-15.

A. Removal

1. Remove engine cowling assembly per Section 53-21.

2. Refer to Figure 71-1. Verify heat shrink stamping is legible (or mark wires and

cables) and remove hardware securing wires and cables to starter-generator studs.

3. Remove starter-generator per RR300 Series Operation and Maintenance Manual (OMM).

B. Installation

1. Install starter-generator per RR300 Series Operation and Maintenance Manual (OMM).

2. Refer to Figure 71-1. Install wires and cables on starter-generator studs according to

stamping. Install hardware, special torque nuts per Section 20-33, and torque stripe

per Figure 5-1.

3. Install engine cowling assembly per Section 53-21.

71-42 Generator Control Unit (GCU)

Refer to R66 Illustrated Parts Catalog (IPC) Figure 71-17.

A. Removal

1. Open baggage compartment door. Remove hardware securing G248-1 cover to

inner compartment and remove cover.

2. Disconnect F049-03 (GCU) electrical harness plug from GCU. Remove mounting

hardware, and remove GCU. Cap receptacles.

B. Installation

1. Open baggage compartment door. Position GCU on inner compartment shelf and

install mounting hardware. Verify security.

2. Remove caps and connect F049-03 (GCU) electrical harness plug to GCU.

NOTE

Verify MS3106R24-28S plug is fully-engaged in GCU receptacle.

Rotate plug collar until tight.

3. Install hardware securing G248-1 cover to inner compartment. Close and secure

baggage door.

Page 71.16

Chapter 71 Powerplant

71-43 Engine Monitoring Unit (EMU)

Refer to R66 Illustrated Parts Catalog (IPC) Figure 71-19.

NOTE

The electronic monitoring unit (EMU) is a serialized component

assigned to the engine. When removing the engine, remove the

engine's EMU per Section 71-43, as required.

A. Removal

1. Remove hardware securing F003-4 (RH) seat back assembly to cabin.

2. Disconnect F059-01 (cabin) electrical harness "EMU" plug and F049-07 (USB)

harness plug from EMU.

3. Remove hardware securing EMU to bulkhead and remove EMU. Cap receptacles.

Installation

1. Remove caps, position EMU on bulkhead, and install hardware. Verify security.

2. Connect F059-01 (cabin) electrical harness "EMU" plug and F049-07 (USB) harness

plug to EMU.

3. Turn BATTERY switch ON. After 10 seconds press annunciator panel test button;

verify EMU amber warning segment illuminates, and is solid, indicating normal EMU

operation. (See R66 Pilot's Operating Handbook Section 7 for complete description.)

Turn BATTERY switch OFF.

4. Install hardware securing F003-4 (RH) seat back assembly to cabin.

C. Downloading EMU Data

NOTE

An EMU USB receptacle is located inside the aft right seat

baggage compartment, on the underside of the aft ledge. Use a

flashlight and mirror when inserting USB cable into receptacle.

Download summary or diagnostic data per RR300 Series Operation and Maintenance

Manual (OMM).

Chapter 71 Powerplant

Page 71.17

CHAPTER 75

ENGINE AIR SYSTEMS

75-00 Description

This chapter includes a description of the engine anti-ice system. Refer to RR300 Series

Operation and Maintenance Manual (OMM) and manufacturer’s maintenance publications for

system-specific inspection, repair, and maintenance procedures.

The Rolls-Royce engine model 250-C300/A1 anti-ice system provides hot compressor discharge

air to the compressor front support. Areas of the front support are subject to ice formation

when the engine is operated near or below freezing temperatures and visible moisture is present.

An anti-ice switch located on the cyclic box cover is selected by the pilot in certain conditions

(see R66 Pilot's Operating Handbook).

The engine anti-ice system includes an air valve, a solenoid valve, and a pressure switch. The

air valve is mounted on top of the compressor scroll; the solenoid valve and pressure switch

are mounted on top of the compressor. When anti-ice is switched "ON", the solenoid valve de-

energizes, the pressure-activated air valve opens, the pressure switch closes which illuminates

the green anti-ice segment on the annunciator panel, and hot, compressed-air is routed to

hollow passages in the front support vanes and center hub.

Anti-ice system operation will result in some performance degradation due to hot induction air

and reduced air-volume reaching the power and gas producing turbine stages.

The anti-ice solenoid valve is electrically-closed, or powered-off. Anti-ice will automatically

function in the event of an electrical failure.

75-10 Engine Anti-Ice

See RR300 Series Operation and Maintenance Manual (OMM) for anti-ice system maintenance.

25 OCT 2010

Chapter 75 Engine Air Systems

Page 75.1

CHAPTER 76

ENGINE CONTROLS

76-00 Description

A twist grip throttle control is located on each collective stick. The controls are interconnected

and actuate the Rolls-Royce engine model 250-C300/A1 fuel control input lever via a push-pull

cable. The throttle is normally not used for control but is set either fully closed (idle position)

or fully open.

The engine incorporates a hydromechanical governor which attempts to maintain 100% engine

output shaft RPM when the throttle is in the open position. A linkage provides the power

turbine governor with collective inputs to help anticipate changing power demands.

Large power changes or varying environmental conditions may cause the governor RPM setting

to vary by a few percent. A momentary toggle switch (beep switch) on the collective stick is

provided to trim, or "beep", the governor setting to the desired RPM. The switch controls an

actuator which adjusts the linkage between the collective and power turbine governor.

The governor controls RPM under normal conditions. It may not prevent over- or under-speed

conditions generated by aggressive flight maneuvers or rapid power changes.

Other engine controls include a push-pull fuel cutoff control on the console face, a start button

on the pilot's collective, a key-type igniter switch, and an anti-ice switch.

76-10 Fuel Control Unit (FCU)

Refer to R66 Illustrated Parts Catalog (IPC) Figure 76-1.

A. Removal

1. Pull fuel valve OFF. Remove engine cowling assembly per Section 53-21.

2. Refer to Figure 76-1. Remove fasteners securing C522-10 throttle and A522-10 fuel

cutoff control inner wires to FCU throttle and fuel cutoff levers.

3. Remove fasteners securing control housings and AN742-4 clamps to F577 bracket

assemblies, as required.

4. Remove FCU per RR300 Series Operation and Maintenance Manual (OMM).

5. If sending FCU to repair facility, remove F147-1 (minimum throttle stop) screw and

D930-2 spring.

Installation

1. If removed: Install F147-1 (minimum throttle stop) screw, special torque screw per

Section 20-33, and torque stripe per Figure 5-1. Install D930-2 spring.

2. Install FCU per RR300 Series Operation and Maintenance Manual (OMM).

3. Perform throttle control rigging per Section 76-11.

4. Perform fuel cutoff control rigging per Section 76-12.

5. Push fuel valve ON.

Chapter 76 Engine Controls

Page 76.1

76-11 FCU Throttle Control Rigging

Remove engine cowling assembly per Section 53-21. Remove F461-1 collective cross

tube cover and (copilot) F680-1 collective cover assembly (see Section 6-70).

Refer to Figure 76-1. Verify FCU throttle lever rigging angle is 48.5° ± 7.5°. As

required, remove hardware securing serrated levers and reposition to proper angle.

Install hardware, special torque nut per Section 20-33, & torque stripe per Figure 5-1.

Remove palnuts and loosen nuts securing A462-4 fittings and C522-10 (throttle) control

inner wire to collective arm and to FCU throttle lever.

Position forward end of control housing flush-0.25 inch at or beyond edge of outboard

AN742-3 clamp and install fasteners securing housing and clamps to F764-1 collective

stick weldment.

Refer to detail in Figure 76-3. Rotate collective stick twist grip open. Position inner

wire 0.10-0.30 inch beyond outboard edge of fitting in collective arm, and special

torque fitting nut per Section 20-33. Install palnut, standard torque per Section 20-32,

& torque stripe per Figure 5-1.

Position aft end of control housing 1.10-1.30 inches beyond edge of aft AN742-4 clamp

and install fasteners securing housing and clamps to F577-3 bracket.

Refer to detail in Figure 76-3. Rotate twist grip closed; rotate and hold FCU throttle

lever to contact idle stop. Verify sufficient inner wire beyond aft edge of fitting, and

special torque fitting nut per Section 20-33.

Rotate twist grip open; verify FCU throttle lever contacts maximum throttle stop,

and 0.030-0.050 inch gap between F328-1 connecting rod and throttle stop washer.

Reposition fitting on wire as required until proper rod-to-washer gap, and FCU throttle

lever contacts maximum throttle stop with twist grip open, and idle stop with twist grip

closed.

Install fitting palnut, standard torque per Section 20-32, and torque stripe per Figure

5-1. Trim control wire 0.10-0.30 inch beyond aft edge of fitting.

10.

Install collective cross tube cover and collective cover assembly. As required, perform

FCU fuel cutoff control rigging per Section 76-12, or install engine cowling assembly

per Section 53-21.

76-12 FCU Fuel Cutoff Control Rigging

1. Remove engine cowling assembly per Section 53-21.

2. Refer to Figure 76-1. Remove palnut and loosen nut securing A462-4 fitting and A522-

10 (fuel cutoff) control inner wire to FCU fuel cutoff lever.

3. Rotate FCU fuel cutoff lever into OFF detent; pull fuel cutoff control knob OFF (at

lower console). Position end of control housing flush-0.050 inch from forward edge of

fitting and install fasteners securing housing and AN742-4 clamps to F577-1 bracket

assembly.

4. Refer to detail in Figure 76-3. Verify sufficient inner wire beyond aft edge of fitting, and

special torque fitting nut per Section 20-33.

25 OCT 2010

Chapter 76 Engine Controls

Page 76.3

76-12 FCU Fuel Cutoff Control Rigging (continued)

5. Push fuel cutoff control knob ON and verify FCU fuel cutoff lever-to-maximum fuel

stop clearance is 0.030-0.090 inch. Reposition fitting on wire as required until FCU

fuel cutoff lever rests in detent when control is OFF and has required clearance from

maximum fuel stop when control is ON.

6. Install fitting palnut, standard torque per Section 20-32, and torque stripe per Figure

5-1. Trim control wire 0.10-0.30 inch beyond aft edge of fitting.

7. Install engine cowling assembly per Section 53-21.

76-20 Power Turbine Governor (PTG)

Refer to R66 Illustrated Parts Catalog (IPC) Figures 76-5 and 76-7.

A. Removal

1. Remove engine cowling assembly per Section 53-21.

2. Refer to Figure 76-2. Remove cotter pin and washer securing C522-11 (power turbine

governor) control inner sleeve and D333-13 fitting to PTG input lever.

3. Remove fasteners securing control housing and AN742-4 clamps to F046-1 lower frame,

as required.

4. Remove PTG per RR300 Series Operation and Maintenance Manual (OMM).

Installation

1. Install PTG per RR300 Series Operation and Maintenance Manual (OMM).

2. Perform PTG control rigging per Section 76-21.

76-21 PTG Control Rigging

1. Remove engine cowling assembly per Section 53-21. Detach center back rest assembly

hook and loop tape (Velcro) at bottom; slide back rest assembly up and out of keyhole

slots. Remove F474-2 middle seat cover (see Section 6-70).

2. Refer to Figure 76-2. Verify PTG input lever rigging angle is 93.0° ± 7.5°. As required,

remove hardware securing serrated levers and reposition to proper angle. Install

hardware, special torque nut per Section 20-33, and torque stripe per Figure 5-1.

3. Refer to Figure 76-3. Remove palnut and loosen nut securing A462-4 fitting and C522-

11 (power turbine governor) control inner wire to F822-1 bellcrank assembly.

4. Position PTG pointer to indicate 45° on PTG protractor. Position aft end of control

housing 1.44-1.50 inches from forward edge of D333-13 fitting and install fasteners

securing housing and AN742-4 clamps to F046-1 lower frame.

5. Position forward end of control housing flush-0.25 inch at or below edge of bottom

AN742-3 clamp and install fasteners securing housing and clamps to F381-6 bracket.

6. Turn BATTERY switch ON. With collective stick full down, “beep” collective toggle

switch to full down. Turn BATTERY switch OFF.

25 OCT 2010

Chapter 76 Engine Controls

Page 76.5

76-21 PTG Control Rigging (continued)

7. Verify PTG pointer indicates 45° on PTG protractor, verify sufficient inner wire beyond

bottom edge of bellcrank fitting, and special torque fitting nut per Section 20-33.

8. Install palnut, standard torque per Section 20-32, and torque stripe per Figure 5-1. Trim

control wire 0.10-0.30 inch beyond bottom of fitting.

9. Perform PTG rigging check per Section 76-22.

10. Install engine cowling assembly per Section 53-21. Install middle seat cover. Install

back rest assembly in keyhole slots and slide down; press firmly on back rest assembly

hook and loop tape at bottom. Verify security.

76-22 PTG Rigging Check

1. Turn BATTERY switch ON.

2. Refer to Figure 76-2. With collective stick full down, “beep” collective toggle switch to

full down. Verify PTG pointer indicates between 42.5° and 47.5° on PTG protractor.

Turn BATTERY switch OFF.

3. Adjust PTG control rigging as required per Section 76-21; repeat previous steps until

PTG is rigged for proper mechanical range.

4. Run-up helicopter per R66 Pilot's Operating Handbook, Section 4. Verify “beep” range

is 97 to 103% rotor RPM with collective full down and twist grip open.

5. Adjust PTG control rigging as required per Section 76-21; repeat previous steps until

PTG is rigged for proper operational range.

25 OCT 2010

Chapter 76 Engine Controls

Page 76.7

CHAPTER 79

ENGINE OIL SYSTEM

79-00 Description

The R66 helicopter has a dry-sump engine oil system. Oil is stored in a remote tank located in

the main rotor gearbox compartment. Refer to Section 12-60 for oil servicing instructions. A

Rolls-Royce-supplied oil temperature sender is mounted on the inboard side of the oil tank.

Oil circulates through the engine oil system via three oil delivery lines. Refer to Figure 79-1.

Cool oil exits the oil tank and enters the engine, hot oil exits the engine and enters the engine

oil cooler, and cooled oil exits the oil cooler and returns to the oil tank. An oil tank vent line is

plumbed to the engine accessory gearbox, which is vented to the exhaust pipe.

The engine oil cooler has an internal thermostat and pressure relief valve. The thermostat

maintains normal system operating pressure by allowing cool oil to bypass the heat exchanger

and return to the oil tank. Higher than normal system pressure will open a pressure relief valve.

When draining the oil system, residual oil is trapped in the bottom corner of the oil cooler due

to the oil cooler installation angle in the R66. An oil cooler drain plug allows the technician to

drain trapped oil during servicing.

The engine oil system includes an oil pump, oil filter and regulating valve, an oil sump tank, a

check valve, and two magnetic plug inserts. Refer to RR300 OMM for a complete description

of the engine oil system.

FIGURE 79-1 ENGINE OIL SYSTEM SCHEMATIC

Chapter 79 Engine Oil System

Page 79.1

79-10 Scroll and Fanwheel Assemblies

Refer to R66 Illustrated Parts Catalog (IPC) Figure 79-1.

A. Removal

1. Remove F196-1 fan shaft per Section 65-10.

2. Refer to Figure 79-2. Remove perimeter screws securing F236-1 scroll assembly to

F306-1 box assembly.

3. Remove aluminum tape sealing gaps & joints, or gently pull scroll away from box

assembly and, using a scribe or similar sharp instrument, tear aluminum tape sealing

gaps & joints. Remove scroll, with G174-1 fanwheel assembly inside, up through

frame.

4. Remove hardware securing forward or aft F305-5 inlet to scroll; remove inlet & fanwheel.

Remove damaged aluminum tape from scroll and box assembly.

Installation

1. Refer to Figure 79-2. Observing “AFT” orientation marking on fanwheel plate, place

G174-1 fanwheel assembly inside F236-1 scroll assembly accordingly. Position F305-5

inlets on scroll and install hardware. Verify security.

2. Lower scroll, with fanwheel inside, through frame and install hardware securing scroll

to F306-1 box assembly. Verify security. Seal gaps & joints using A701-1 aluminum

tape.

3. Install F196-1 fan shaft per Section 65-10.

79-11 Fanwheel-to-Inlet Gaps

A. Measuring Gap

1. Remove tailcone cowling assembly per Section 53-23.

2. Refer to Figure 79-2. Verify 0.10 inch minimum gap between G174-1 fanwheel

assembly and forward and aft F305-5 inlets. Check gap all the way around; rotate

fanwheel and check gap again (several positions). If gap is within limits at forward

and aft inlets, no further action is required.

3. Verify proper tail rotor driveline shimming per Section 65-30.

4. Trim inlets as required per Part B.

5. Install tailcone cowling assembly per Section 53-23.

Chapter 79 Engine Oil System

Page 79.3

79-11 Fanwheel-to-Inlet Gaps (continued)

Trimming Inlets

1. Refer to Figure 79-2. Remove hardware securing F305-5 inlets to F236-1 scroll

assembly.

2. If inlets are slotted, carefully twist inlets over F196-1 fan shaft and remove inlets. If

inlets are not slotted, remove hardware securing fan shaft to C947-3 plate assemblies,

noting hardware removed, and remove inlets.

3. Refer to Figure 79-2, Detail A. Trim inlets as required to meet minimum fanwheel-

to-inlet gap. Do not exceed minimum inlet dimensions.

4. Refer to Section 20-70. Smooth inlet edges and coat bare metal with primer. Touch-

up primed area using dark gray Dupont Imron polyurethane enamel in accordance

with paint manufacturer’s recommendations.

5. If inlets are slotted, carefully twist inlets over fan shaft and install hardware securing

inlets to scroll assembly (slot orientation is optional). Verify security.

6. If inlets are not slotted, install inlets around fan shaft and install hardware securing

inlets to scroll assembly. Verify security. Install hardware securing fan shaft to

plate assemblies, standard torque nuts and palnuts per Section 20-32, and torque

stripe per Figure 5-1.

7. Measure fanwheel-to-inlet gaps per Part A. Repeat procedure as required for minimum

0.10 inch gap at forward and aft inlets.

79-20 Oil Tank Assembly

Refer to R66 Illustrated Parts Catalog (IPC) Figure 79-5.

A. Removal

1. Drain engine oil per Section 12-60.

2. Remove tailcone cowling assembly per Section 53-23. Open main rotor gearbox

compartment access door.

3. Refer to Figure 79-3. Cut and discard safety wire securing tube to G689-1 oil tank

assembly scupper drain. Pull tube off of drain.

4. Disconnect harness assembly plug from MS28034-1 oil temperature sender (located on

inboard side of tank).

5. Remove hardware securing line assembly clamps.

6. Loosen F723-1, F723-3, and F723-4 line assembly B-nuts from engine, F649-1 oil

cooler, and tank fittings; disconnect lines from tank fittings and plug lines.

7. Remove nuts securing tank fittings to firewall.

8. Remove hardware securing tank tabs to F384-3 angles. Remove tank through access

door and cap fittings.

Chapter 79 Engine Oil System

Page 79.5

79-20 Oil Tank Assembly (continued)

B. Installation

1. Refer to Figure 79-3. Remove caps from G689-1 oil tank assembly fittings.

2. Torque check union at oil cooler, and torque check engine (oil line) unions and check

valve per Section 20-33.

3. Insert tank through main rotor gearbox compartment access door. Install hardware

securing tank tabs to F384-3 angles.

4. Install nuts securing tank fittings to firewall and special torque nuts per Section 20-33.

5. Remove plugs and connect F723-1, F723-3, and F723-4 line assembly B-nuts to tank

fittings. Special torque B-nuts at tank, F649-1 oil cooler, and engine per Section 20-33

and torque stripe fittings.

6. Install hardware securing line assembly clamps.

7. Connect harness assembly plug to oil temperature sender (located on inboard side of

tank).

8. Fit tube onto tank scupper drain. Wrap tube with two turns 0.032-inch diameter lockwire

and safety tube to drain.

9. Service engine oil per Section 12-60.

10. Install tailcone cowling assembly per Section 53-23.

79-21 Oil Temperature Sender

Refer to R66 Illustrated Parts Catalog (IPC) Figure 79-5.

A. Removal

1. Drain engine oil per Section 12-60.

2. Remove tailcone cowling assembly per Section 53-23.

3. Refer to Figure 79-3. Disconnect harness assembly plug from MS28034-1 oil

temperature sender (located on inboard side of G689-1 oil tank assembly).

4. Remove sender and gasket from tank, and discard gasket.

5. Tape sender opening to protect tank from contaminants.

B. Installation

1. Refer to Figure 79-3. Remove tape from G689-1 oil tank assembly sender opening

and verify tank interior is free of contaminants.

2. Install new gasket on MS28034-1 oil temperature sender, and install sender in

inboard side of tank. Special torque sender per Section 20-33.

3. Connect harness assembly plug to sender.

4. Service engine oil per Section 12-60.

5. Install tailcone cowling assembly per Section 53-23.

Page 79.6

Chapter 79 Engine Oil System

79-22 Sight Gage

Refer to R66 Illustrated Parts Catalog (IPC) Figure 79-5.

A. Removal

1. Drain engine oil per Section 12-60.

2. Refer to Figure 79-3. Remove B563-2 sight gage and o-ring from G689-1 oil tank

assembly. Discard o-ring.

3. Tape gage opening to protect tank from contaminants.

B. Installation

1. Refer to Figure 79-3. Remove tape from G689-1 oil tank assembly gage opening and

verify tank interior is free of contaminants.

2. Lubricate new o-ring using approved turbine engine oil per R66 Pilot’s Operating

Handbook (POH) Section 8. Install o-ring on B563-2 sight gage, and install gage in

tank. Special torque gage per Section 20-33.

3. Service engine oil per Section 12-60.

79-30 Engine Oil Cooler

Refer to R66 Illustrated Parts Catalog (IPC) Figure 79-7.

A. Removal

1. Drain engine oil per Section 12-60.

2. Refer to Figure 79-3. Remove fasteners securing F649-1 oil cooler to F309-1 box

assembly.

3. Remove hardware securing line assembly clamps.

4. Support oil cooler without damaging oil cooler fins. Loosen F723-2 and F723-4 line

assembly B-nuts at engine, oil cooler, and G689-1 oil tank assembly fitting; disconnect

lines at oil cooler unions. Cap unions and plug lines.

Installation

1. Refer to Figure 79-3. Remove F649-1 oil cooler union caps. Torque check oil cooler

unions and engine (oil line) union or check valve (early R66s) per Section 20-33.

2. Remove plugs and connect F723-2 and F723-4 line assembly B-nuts to oil cooler fittings.

Special torque B-nuts at tank, oil cooler, and engine per Section 20-33 and torque stripe

fittings.

3. Install hardware securing line assembly clamps.

4. Install hardware securing F649-1 oil cooler to F309-1 box assembly.

5. Service engine oil per Section 12-60.

Chapter 79 Engine Oil System

Page 79.7

79-40 Engine Oil Line Assemblies and Fittings

Refer to R66 Illustrated Parts Catalog (IPC) Figure 79-9.

A. Removal

1. Drain engine oil per Section 12-60.

2. Refer to Figure 79-3. Remove hardware securing line assembly clamps.

3. Disconnect F723 line assembly B-nuts from engine, F649-1 oil cooler, and/or G689-1

oil tank assembly fittings, as required. Cap fittings and plug lines.

4. Carefully remove line assembly from engine compartment.

Installation

1. Refer to Figure 79-3. Remove caps from unions. Torque check F649-1 oil cooler

unions and/or G689-1 oil tank assembly nuts per Section 20-33; torque check engine

(oil line) unions and/or check valve (early R66s) per Section 20-33, as required.

2. Remove plugs and connect F723 line assembly B-nuts to engine, oil cooler, and/or tank,

as required. Verify 0.2 inch minimum clearance between shaft weldment and firewall

grommet; verify equal gap concentrically between shaft and box assembly hole edges.

Adjust F174-1 support weldment rod ends per Section 53-31 as required. Special

torque B-nuts per Section 20-33 and torque stripe fittings.

3. Install hardware securing line assembly clamps.

4. Service engine oil per Section 12-60.

Page 79.8

Chapter 79 Engine Oil System

CHAPTER 95

INSTRUMENT SYSTEM

Section

Title

Page

95-00

Description

95.1

95-10

Pitot-Static System

95.3

95-20

Primary Instruments

95.5

95-21

Vertical Speed Indicator

95.5

95-22

Airspeed Indicator

95.5

95-23

Engine (N2) and Rotor Dual Tachometer

95.5

95-24

Altimeter

95.5

95-25

Torquemeter

95.6

95-26

Magnetic Compass

95.6

95-30

Engine Gages

95.6

95-31

N1 Tachometer

95.6

95-32

Measured Gas (Turbine) Temperature (MGT) Gage

95.6

95-33

Engine Oil Pressure Gage

95.6

95-34

Engine Oil Temperature Gage

95.6

95-35

Fuel Quantity Gage

95.6

95-40

Additional Standard Indicating Equipment

95.7

95-41

Clock

95.7

95-42

Ammeter

95.7

95-43

Outside Air Temperature (OAT) Gage/Voltmeter

95.7

95-44

Hourmeters

95.7

95-50

Instrument Markings

95.7

95-60

Troubleshooting Guide

95.7

25 OCT 2010

Chapter 95 Instrument System

Page 95.i

CHAPTER 95

INSTRUMENT SYSTEM

95-00 Description

Standard primary instruments are a vertical speed indicator, airspeed indicator, engine (N2)

and rotor dual tachometer, altimeter, torquemeter, and magnetic compass. Engine gages

include an N1 tachometer, measured gas (turbine) temperature, oil pressure, oil temperature,

and fuel quantity. Also standard are a clock, an ammeter, a digital outside air temperature

gage/voltmeter, and an hourmeter. An additional hourmeter is located outboard of the pilot's

seat. Both hourmeters require main gearbox oil pressure to activate. The outboard hourmeter

is collective activated and is approved for recording time in service. Space is provided for

optional instruments and avionics.

The pitot-static system supplies air pressure to operate the airspeed indicator, altimeter, and

vertical speed indicator. The pitot tube is located on the front edge of the mast fairing. The

static sources are located on each side of the cabin, aft of the rear doors.

Water can be drained from pitot-static lines by removing the plastic drain plugs which are

accessible through the aft inspection panel on the underside of the cabin. Draining lines should

be required only if the airspeed indicator or altimeter appears erratic.

Pitot and static sources should be inspected frequently for bugs or other obstructions, or if

condensation appears inside connected instruments.

25 OCT 2010

Chapter 95 Instrument System

Page 95.1

95-10 Pitot-Static System

A. Pitot System Leak Test

CAUTION

Do not apply suction to pitot system or pressure to static system.

1. Open mast fairing per Section 53-22.

2. Refer to Figures 95-1 and 95-2. Seal drain hole in elbow aft of pitot tube with pressure

sensitive tape. Connect a medical syringe, with plunger withdrawn, to pitot tube via

flexible tubing.

3. SLOWLY apply pressure to pitot line by depressing syringe plunger until airspeed indicator

reads 70 knots. Release force on plunger; plunger will remain in place without need to

pinch flexible tubing.

4. Gently tap airspeed indicator glass to remove friction effects.

5. If airspeed indication drops more than 10 knots in one minute, an unacceptable leak is

indicated. SLOWLY release pressure. Locate and repair any leak(s). Retest after any

repairs.

6. Remove tape from pitot tube drain hole and verify airspeed indicator has returned to

zero.

7. Remove test equipment.

Static System Leak Test

CAUTION

Airspeed indicator, altimeter, and vertical speed indicator may be

damaged if suction to static line is applied or removed rapidly.

1. Refer to Figures 95-1 and 95-2. Set altimeter to location elevation.

2. Temporarily seal left or right side static opening with pressure sensitive tape. Cover

remaining static port with a suction cup attached to a medical syringe.

3. SLOWLY apply suction to static port by withdrawing syringe plunger until altimeter

indicates 500 feet greater than location elevation. Release force on plunger, wait one

minute, and note any change in altimeter indication.

4. Change of less than 100 feet indication in one minute is acceptable. SLOWLY remove

suction from static port. Locate and repair leak(s) if altimeter indication changes 100 or

more feet in one minute. Retest after any repairs.

5. Remove test equipment.

25 OCT 2010

Chapter 95 Instrument System

Page 95.3

95-20 Primary Instruments

95-21 Vertical Speed Indicator

The vertical speed indicator indicates rate of ascent or descent. Check vertical speed

indicator for a zero-rate needle indication when rotorcraft is in a stationary hover.

95-22 Airspeed Indicator

The airspeed indicator displays airspeed in knots and miles per hour. The airspeed

indicator operates in forward flight only; backward or lateral flight will not indicate correct

airspeed.

95-23 Engine (N2) and Rotor Dual Tachometer

CAUTION

Installation of electrical devices can affect accuracy and reliability

of electronic tachometers.

An electronic engine (N2) and rotor dual tachometer is standard. Engine tachometer signal

is provided by a transducer on the engine gearbox. Rotor tachometer signal is provided by

magnets on the main gearbox tail rotor driveline yoke. Each tachometer is on a separate

circuit with its own circuit breaker. The tachometer bus receives power from the avionics

bus or through the battery relay bypass circuit as long as the main rotor gearbox has

oil pressure. Therefore, the tachometers will receive power through the bypass circuit

whenever the rotors are turning even if the avionics bus is not powered. The bypass circuit

is disconnected from the tachometer bus when the annunciator test button is depressed.

Pressing the test button while the helicopter is running will confirm that the tachometers

are receiving power from the avionics bus.

A. Adjustment

NOTE

The dual tachometer is preset at RHC. Slight variations between

rotorcraft may require tachometer adjustment.

1. Open upper console.

2. Run-up helicopter per R66 Pilot's Operating Handbook (POH) Section 6 at 100%

engine tachometer indication.

3. Turn adjustment screw on back of tachometer clockwise to increase and

counterclockwise to decrease rotor tachometer indication

(one-half turn equals

approximately 1% change). Adjust rotor tachometer to indicate 100%.

4. Shutdown helicopter per R66 POH Section 6. Close and secure upper console.

95-24 Altimeter

The sensitive altimeter provides altitude information relative to mean sea level when the

barometric pressure correction scale is properly set. Check altimeter calibration by setting

correction scale to the current altimeter setting and checking the altimeter reading against

location elevation; they must agree within 70 feet.

25 OCT 2010

Chapter 95 Instrument System

Page 95.5

95-25 Torquemeter

The electronic torquemeter indicates percent torque. The torque sensor is an oil pressure

transducer mounted on the front of the engine's accessory gearbox.

95-26 Magnetic Compass

An internally illuminated, wet-type compass is attached to the center bow between the

windshields above the instrument panel. A compass correction card is aft of the windshield

above the pilot's seat.

95-30 Engine Gages

95-31 N1 Tachometer

The electronic N1 tachometer indicates percent RPM of the engine's gas producer section.

The N1 sensor is a sealed variable-reluctance, permanent-magnet device mounted atop the

engine's accessory gearbox adjacent to the hoisting lug.

95-32 Measured Gas (Turbine) Temperature (MGT) Gage

The measured gas temperature (MGT) gage connects to the engine's thermocouple harness

via different size connectors to ensure correct polarity. Refer to RR300 Series Operation

and Maintenance Manual (OMM) for periodic calibration requirements.

95-33 Engine Oil Pressure Gage

The engine oil pressure gage is electronic. The oil pressure sensor is a transducer mounted

on the lower front of the engine's accessory gearbox.

95-34 Engine Oil Temperature Gage

The engine oil temperature gage is electronic. The oil temperature sensor is a transducer

mounted on the inboard wall of the oil tank.

95-35 Fuel Quantity Gage

The electric fuel quantity gage indicates relative fuel quantity. The variable resistance

sender is mounted near the fuel cap.

Page 95.6

Chapter 95 Instrument System

25 OCT 2010

95-40 Additional Standard Indicating Equipment

95-41 Clock

A manually set electric analog clock is standard equipment; a digital clock is optional.

95-42 Ammeter

The ammeter indicates electrical system loads. System load is measured at the shunt

located on the left side of the vertical firewall in the engine compartment.

95-43 Outside Air Temperature (OAT) Gage/Voltmeter

NOTE

No cutting or splicing of OAT probe wires is permitted.

The outside air temperature gage is connected via a calibrated, twisted pair wiring harness

to a stainless steel probe protruding from the chin.

95-44 Hourmeters

Two hourmeters are standard. One hourmeter is mounted above the ammeter and is

activated by main gearbox oil pressure. Another hourmeter on the horizontal panel outboard

of the pilot's seat is activated by a combination of main gearbox oil pressure and a raised

collective and is approved for recording time in service.

95-50 Instrument Markings

See R66 Pilot's Operating Handbook (POH) Section 2 for instrument markings.

95-60 Troubleshooting Guide

Vertical Speed Indicator

Climb indication with no return to

No Indication

Erratic Indication

zero in level flight.

• Defective indicator.

• Water in static system.

• Blockage in the static line.

• Defective indicator.

Airspeed Indicator

No Indication

Erratic Indication

• Blockage of pitot tube.

• Loose pitot or static line connection.

• Disconnected pitot tube.

• Broken pitot line.

• Kinks (bends) in pitot line

• Water in pitot-static system.

under upper console.

• Defective instrument.

• Defective indicator.

Altimeter

No Indication

Erratic Indication

• Blockage in static line.

• Water in static line.

• Defective instrument.

25 OCT 2010

Chapter 95 Instrument System

Page 95.7

Robinson Helicopter Company RTR 660 (Number R00015LA). Maintenance Manual (2012) - page 5