HANDBOOK OF MAINTENANCE INSTRUCTIONS FOR MDHI 369D/E/FF-500/600N HELICOPTERS (ISSUED: 1990)

MD Helicopters, Inc.

CSP-HMI-2

MAINTENANCE MANUAL

ANTI−TORQUE FLIGHT CONTROLS

(TWO AND FOUR BLADE)

INSPECTION/CHECK

1. Upper Fuselage and Tailboom Control

2. Tail Rotor Pedal Assembly Inspection

Linkage Inspection

(Ref. Figure 402)

(Ref. Figure 401)

(1).

Inspect rod end bearings for binding

NOTE: Inspect components at left and right po

and excessive wear, 0.040 inch (1.016

sition on the right-hand command models.

mm) maximum axial play. Inspect rivet

Check that corresponding pedals contact

at fixed rod end.

stops simultaneously.

(2).

Inspect control rod for surface damage

(1).

Inspect pedals and pedal arms for

and evidence of bending.

cracks, elongated pedal attach holes

(3).

Inspect rubber boot just forward of Sta.

and open drain holes. Inspect teflon-

137.50 bulkhead for condition.

reinforced bushing liners for deteriora

tion.

(4).

Inspect tailboom control rod surfaces

that pass through all grommets.

(2).

Inspect pedal-to-arm quick-release

Serviceable wear is limited to thickness

locking pin for condition and positive

of hard anodic coating. Check that all

spring action.

bushings are secure.

(5).

Inspect bellcranks for scratches, cracks,

(3).

Inspect links and bellcrank for cracks

corrosion and similar surface defects.

and bends, and bearings for excessive

play.

(6).

Inspect bellcrank bearings for looseness

and binding.

(4).

Inspect control rod fitting, torque tube

mounting bracket and pedal mounting

(7).

Inspect for obstructions in drain slot of

bracket for cracks and corrosion. Using

Sta. 284 bellcrank.

an 8-power magnifying glass, mirror

(8).

Inspect for corrosion or excessive wear

and flashlight, closely inspect pedal

on Sta. 284 bellcrank pivot pin.

link bellcrank fitting of pedal bracket in

center forward area where fitting (fork

(9).

Visually inspect doublers on Sta. 142

piece) joins tubular section. If any

bellcrank supports for cracking/da

cracks are detected, replace bracket

mage.

assembly. Inspect bracket bearings for

excessive looseness.

NOTE: MDHC Notice DN-49 contains infor

mation relative to repair of damaged dou

blers on bellcrank supports. MDHC Notice

(5).

Inspect torque tube for cracks,

DN-102 contains information required to

scratches, nicks, dents and similar

modify the particle separator fairing and

surface defects.

cover assemblies to prevent possible chafing

of the Sta. 120 tail rotor control rod.

(6).

Inspect pedal brackets for corrosion.

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MAINTENANCE MANUAL

Table 601. Isolating Control System Troubles

Symptom

Isolating Step

Corrective Action

Binding, locking−up and erratic

Disconnect pitch control links from

If symptom is gone, replace tail rotor

action of foot pedals (Do not force

pitch control assembly.

assembly. Repair (Ref. COM).

controls).

Symptom remains.

Disconnect Sta. 284 aft boom

If symptom is gone, clean

bellcrank from pitch control

swashplate bore and output shaft

assembly.

splines. Lubricate splines. Replace

swashplate if necessary. Check for

elongation of bolt hole in support arm

portion of main housing assembly of

tail rotor gearbox, caused by

looseness of bellcrank fulcrum bolt

and nut. Repair (Ref. COM).

Symptom remains.

Disconnect floor−routed tail rotor

If symptom is gone, inspect tail rotor

control rod from foot pedal torque

control rods and bellcranks until

tube fitting.

defective part is located.

Symptom remains.

Loosen foot pedal torque tube

If symptom is gone, pedal torque

brackets mounted on front of floor

tube misaligned; shim for correct

structure.

alignment. If symptom remains,

disassemble and inspect tail rotor

control foot pedal installation until

defective part is located.

Trouble corrected.

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CSP-HMI-2

MAINTENANCE MANUAL

ANTI−TORQUE FLIGHT CONTROLS

(TWO AND FOUR BLADE)

REPAIRS

1. Floor− and Tunnel−Routed Control Rods

(5). If removed, install rivet to secure rod

end.

(Ref. Figure 401 and Figure 402) The floor-

and tunnel-routed control rods connect the tail

(6). Check that slotted bushing is in place;

rotor pedal installation with the upper

then secure control rod in torque tube

fuselage and tailboom control linkage. The two

fitting or idler bellcrank with bolt, two

control rods are linked by a tail rotor idler

washers, nut and cotter pin.

bellcrank mounted on the underseat controls

(7). Install bungee spring.

support bracket.

(8). Install access doors.

2. Floor−Routed Tail Rotor Control Rod

Repair

(9). Check rigging of tail rotor controls (Ref.

Tail Rotor Controls Rigging).

(Ref. Figure 401) Replace rod end if bearing

axial play is more than 0.040 inch (1.016 mm).

3. Upper Fuselage and Tailboom Control

Riveted rod end bearing is replaceable without

Linkage Repair

rod removal if located at forward end of rod. If

(Ref. Figure 401)

riveted rod end is aft, rod removal is required

to replace rod end bearing.

Consumable Materials

NOTE: Floor-routed control rod normally does

(Ref. Section 91−00−00)

not require replacement unless helicopter

Item

Nomenclature

receives extensive impact or crash damage.

CM318

Primer

Remove control rod forward through land

CM431

Sealing, locking and retaining compound

ing light wiring grommet hole after landing

light (if installed) is removed (Ref. Chap.

CM802

Abrasive cloth, aluminum oxide

96).

(1). Perform straightness check on control

(1). Disconnect control rod from pedal

torque tube fitting or from tail rotor

rod that appears bent or bowed. Total

idler bellcrank (Ref. Figure 402).

length of Sta. 120 control rod, excluding

Remove bungee spring (Ref. Sec.

rod ends, must be straight within 0.040

67-10-00).

inch (1.016 mm), with straightness

variation limited to maximum of 0.010

(2). Accurately measure and record distance

inch (0.254 mm) in each foot of length.

between unchamfered edge of rod end

Total length of tailboom control rod,

jam nut and center of rod end bearing

excluding rod ends, must be straight

hole.

within 0.120 inch (3.048 mm), with

straightness variation limited to

Use care when drilling to re

maximum of 0.010 inch (0.254 mm) in

CAUTION

move or install riveted rod end;

each foot of length.

rod end is steel and rod is aluminum.

A dye check for cracking

(3). If necessary, drill out rivet. Loosen jam

WARNING

must always be performed

nut and unscrew rod end.

after cold-straightening. Replace

cracked rod, or cracked or bent rod

(4). Screw another rod end into rod to

end.

obtain same measurement made in step

(2). above. Align control rod ends so

(2). Cold-straighten bent rod that is not

that bearings have equal space for

within tolerance (step (1). above)

angular throw; tighten jam nut.

provided there are no nicks or sharp

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MAINTENANCE MANUAL

dents in bend length. Do not use rod

(6). Repair minor surface defects such as

ends to support rod during straighten

scratches, nicks and corrosion on

ing process.

bellcranks and support bracket. Use

abrasive cloth, grade 400 - 600

Use care when drilling to re

(CM802), to smooth out and blend in

CAUTION

move or install riveted rod end;

such defects. Following rework limits

rod end is steel and rod and bearing adapter

represent total limits, including effects

are aluminum.

of all previous repairs to any given

area.

(3). Replace control rod end if bearing axial

play is more than 0.040 inch (1.016

NOTE: Parts identified (Ref. Figure 401) with

mm). Set initial control rod length and

an asterisk ( * ) may be either magnesium or

bearing angularity.

aluminum alloy. For corrosion control and

identification of magnesium and aluminum

(4). Replace unserviceable control rod

alloys, refer to Section 20-40-00.

bearing adapter. Trammel method (or

equivalent) may be used to establish

(a). Cast surfaces may be reworked to

rod length when replacing an adapter.

depth of 0.020 inch (0.508 mm).

(a). Measure length and record position

(b). Flat machined surfaces, except clevis

of rod end in adapter; then remove

inner ears, may be reworked to depth

affected rod end.

of 0.015 inch (0.381 mm). Clevis

inner ear surfaces may be reworked

(b). Comply with precaution above and

to depth of 0.020 inch (0.508 mm).

drill out rivets securing adapter to

rod and aft rod end.

(c). Machined holes may have 0.003 inch

(0.076 mm) removed from bore wall

(c). Install rod end in replacement

in an area no greater than 15 percent

adapter and position at recorded

of circumference and 50 percent of

measurement.

depth.

(d). Fit adapter into rod and position to

(d). All edges may have 0.030 inch (0.762

fit trammel point spacing; pick up

mm) removed except around ma

and drill through existing rivet holes

chined holes, which are limited to

in rod and install rivets to secure

0.010 inch (0.254 mm) chamfer.

adapter to rod; at aft end, drill and

rivet rod end to adapter.

(e). All rework must be smoothly blended

into adjacent surfaces and finish

(5). Replace unserviceable bellcrank and

must be restored (Ref. preceding

support pivot bearings. Install bearing

NOTE).

with grade A locking compound

(CM431). Make sure that bearing seats

(7). Repair surface abrasion on Sta. 120

against bore shoulder.

control rod by smoothing area with

grade 400 abrasive cloth (CM802) and

NOTE:

restoring protective finish with primer

(CM318). Replace rod if wear or depth

D Installation direction of Sta. 142 bell

of repair exceeds 0.004 inch (0.102

crank bearing may be from either side,

mm).

depending on location of bearing shoul

der. There must not be less than 0.010

(8). Replace tailboom control rod if hard

inch (0.254 mm) protrusion of bearing in

anodic coating is worn through and

ner race beyond sides of bellcrank after

aluminum base metal is visible.

bearing is installed.

D If contact is noted between Sta. 142 bell

(9). Replace split or torn boot. Remove Sta.

crank and mount bracket, rework bell

120 control rod. Replace boot and

crank to clear bracket (Ref. Figure 801).

reinstall Sta. 120 control rod.

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CSP-HMI-2

MAINTENANCE MANUAL

BELLCRANK AND SUPPORT

(2 PLS) (NOTE 1)

0.002 IN.

NOTES

A S

(0.508 MM)

2 & 3

0.750 IN.

NOTES

(19.05 MM)

0.090 IN. (2.286 MM) R

2 & 3

MIN.

369A7951-23

(TYP)

BEARING

NOTES:

0.010 MINIMUM CLEARANCE REQUIRED IN THIS AREA.

TREAT MACHINED AREA WITH CHROMIC ACID SOLUTION (CM207).

TOUCH UP COLOR 34151 GREEN (CM304).

G67-2003A

Figure 801. Rework of Sta. 142 Bellcrank Assembly

4. Station 78.50 Tail Rotor (Tunnel−Routed)

temporarily reinstall washer and nut

Control Rod

on bolt.

All tunnel-routed control rods are removed,

(5). Slide pedal bracket and pedal arms off

inspected, repaired and installed in same

end of torque tube.

manner. For initial length and rod end

(6). Do not remove two teflon-lined bush

angularity, Ref. Figure 402. For maintenance

ings from right pedal arm, unless

information, Ref. Sec. 67-10-00.

replacement is required.

A. Tail Rotor Idler Bellcrank

(7). Do not remove two stop bolts, jam nuts

(Ref. Controls Support Bracket and Bellcrank,

on stop bolts or bearings from pedal

Sec. 67-10-00)

bracket unless replacement is required.

(8). Slide torque tube bracket and control

5. Tail Rotor Pedal Disassembly

rod fitting off torque tube.

(Ref. Figure 402)

6. Tail Rotor Pedal Repair

(1). Before disassembly of tail rotor pedal

(Ref. Figure 402)

installation, matchmark mating pedal

arms, links and bellcranks with pedal

brackets to avoid intermixing compo

Consumable Materials

nents between locations at reassembly.

(Ref. Section 91−00−00)

Item

Nomenclature

(2). Disconnect links from pedal arms and

CM425

Sealing compound

bellcrank; remove links.

CM431

Sealing, locking and retaining compound

(3). Remove bellcrank from pedal bracket.

(4). Remove nut and washer of two bushing

(1). Replace parts that are cracked or have

assemblies that secure left pedal arm

elongated attachment holes. Do not

and control rod fitting to torque tube.

attempt to straighten bent torque tube

Carefully remove bushing bolt and

or pedal link.

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MAINTENANCE MANUAL

(2). Replace unserviceable pedal covers.

mm). Torque nut to 50 - 80 inch-

Apply sealing compound (CM425) to

pounds (5.65 - 9.04 Nm) plus drag

approximately 30 percent of upper and

torque. Do not allow bolt to turn.

lower edge surfaces that contact pedal.

Cure according to container instruc

(6).

Check that each end of bushing assem

tions.

bly shank protrudes at least 0.002 inch

(0.051 mm). If not, loosen and repeat

(3). Replace complete pedal link if it is

step (4). above.

cracked or contains unserviceable

(7).

Check that slotted bushing is in place;

bearings; bearings are not replaceable.

then attach bellcrank to pedal bracket

(4). Replace unserviceable bearings in

with bolt, two washers, nut and cotter

mounting brackets or pedal link

pin.

bellcrank. Install replacement with

(8).

Check that slotted bushings are in

grade A locking compound (CM431).

place; then fasten each link to bellcrank

with bolt, two washers, nut and cotter

Right pedal arm bushings are

CAUTION

pin.

glass-filled phenolic. Make cer

tain that bushing does not cock during re

(9).

Check that slotted bushings are in

placement, and that it is fully seated in arm

place; then fasten each link in pedal

bore. Keep tools from contact with bushing

arm lugs with bolt, two washers, nut

liners to avoid fraying.

and cotter pin.

(5). Replace bearings in right pedal arm

(10).

Ensure outboard pedals clear windows

when teflon-reinforced liner is galled or

by a minimum of 0.20 inch (0.508 mm)

frayed. Pull bushing to remove; press to

with 20 pounds (88.96 N) of force

install.

applied.

(6). Remove corrosion from pedal brackets

8. Tail Rotor Bungee Spring Forward

(Ref. Sec. 20-40-00 and CSP-A-3,

Attachment Relocation

Corrosion Control Manual).

(Ref. Figure 802) The information given in this

7. Tail Rotor Pedal Reassembly

procedure is for the relocation of the tail rotor

bungee spring forward attachment on 369D

(Ref. Figure 402)

helicopters, Serial No. 003D - 0467D. This

rework allows for the installation of washers,

(1). When reassembling components, check

for bungee adjustment, to adjust for minimum

for correct matchmark identification.

pedal loads in cruise.

(2). If previously removed, thread jam nut

on each of two stop bolts and install two

Consumable Materials

stop bolts into threaded inserts of pedal

(Ref. Section 91−00−00)

brackets.

Item

Nomenclature

CM207

Chromic acid solution

(3). Slide torque tube bracket and control

rod fitting onto torque tube.

CM318

Primer

CM411

Adhesive, epoxy

(4). Locate pedal bracket and pedal arms

for correct position on torque tube; slide

bracket and arms onto torque tube.

(1). Remove access cover between pilot's

seats and/or passenger's footwell on aft

(5). Fasten left pedal arm and control rod

side of canted bulkhead.

fitting to torque tube with adjustable

bushing assemblies. Install bushing

(2). Block left tail rotor control pedal at full

bolt so that shank at bolt-head end

forward position to relieve tension on

protrudes at least 0.002 inch (0.051

bungee.

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MAINTENANCE MANUAL

(3). Disconnect bungee spring from eyebolt

end of 369D27521 bungee spring to

and remove and retain nut and washer

eyebolt. Insert eyebolt in new hole in

attaching eyebolt to bracket at Sta. 63,

369A2541 bracket and secure with

discard eyebolt.

washer and nut retained from prior

step. Torque nut to 20 - 25 inch-

(4). Locate position and drill new hole using

pounds (2.26 - 2.82 Nm).

No. 10 drill, deburr as required.

NOTE: If tail rotor pedal forces are not zero

(5). Seal old eyebolt hole with adhesive

during level flight at 130 - 140 knots, tail ro

(CM411). Allow to dry per manufactur

tor force adjustment may be accomplished

er's instructions.

by removing a desired number of AN970-3

washers.

(6). Treat edge of new hole with chromic

acid solution (CM207) and touch up

(8). Remove block from left tail rotor control

with zinc chromate primer (CM318).

pedal.

(7). Install eight AN970-3 washers on one

(9). Reinstall access cover between pilot's

AN42B-C10A eyebolt and hook forward

seats and/or passenger's footwell.

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CSP-HMI-2

MAINTENANCE MANUAL

NOTAR® ANTI−TORQUE SYSTEM FLIGHT CONTROLS

DESCRIPTION AND OPERATION

1. NOTAR Anti−Torque System Control

a stability augmentation system

Linkages Configuration and Description

(S.A.S.).

(1). The helicopter may be equipped with

2. Stability Augmentation System

either of two basic configurations,

Description and Operation

single left-hand command or right-

NOTE: Aircraft equipped with YSAS cannot be

hand command, (dual control are

flown with any component of the system re

optional).

moved.

NOTE:

(1).

The Yaw Stability Augmentation

D The 600N helicopter does not have a

System provides increased directional

spring on the splitter assembly like the

stability and allows for a lower pilot

500N helicopter.

workload in the directional axis.

D Some 600N helicopters are not equipped

(2).

The YSAS adds an actuator that is

with a YSAS system.

located inside the right side of the

horizontal stabilizer and is mechanical

D The 600N helicopter has a Sta. 95 bell

ly bolted to the horizontal stabilizer on

crank instead of a Sta. 97.50 Bellcrank.

the outboard side.

(2).

The control linkages for the foot pedals

(3).

Two access panels on the horizontal

installation are identical to the basic

stabilizer allows access to the actuator,

helicopter, with the exception of a pedal

bellcranks, control rod and electrical

friction mechanism with a preset

connectors.

friction tension. The pedal friction

mechanism (500N only) offers the pilot

(4).

A yaw rate gyro is located under the

an artificial feel or workload of a

pilot's seat structure on the foreword

conventional tail rotor system.

bulkhead. Access to the gyro is through

the rear access panel (footwell) Sta.

(3).

A splitter bungee spring (500N only)

78.50 canted bulked.

which is incorporated in the flight

control system at the mast base

The yaw rate gyro provides short term

between the 97.50 bellcrank support

rate signals to the computer, propor

bracket and splitter pinion gear

tional to the rate of angular displace

dampens control feedback.

ment about the axis perpendicular to

the gyro's mounting surface damping in

(4).

Fuselage controls linkages consist of

the directional axis signal electronical

Sta. 97.50 bellcrank and a support at

ly.

the front of the main rotor mast base,

(5).

A YSAS electronic control box (comput

fwd control tube, splitter bungee spring,

er) is installed below the rate gyro. It is

splitter assembly, intermediate control

equipped with an internally-mounted

tube, Sta. 137.50 support bracket and a

lateral accelerometer.

bellcrank at the fan transmission

support assembly, aft control tube and a

The lateral accelerometer enhances

two piece cable assembly to the thrust

direction stability by feeding back to

er.

the YSAS computer signals measured

during flight. The computer processes

(5).

Empennage controls consist of a

the signals received and sends them to

thruster installation, four piece cable

the actuator.

and drum assembly, a control rod,

vertical stabilizer control tubes and

(6).

The 600N helicopters come equipped

bellcranks and, in the case of the 500N,

with an indicator mounted in the

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MAINTENANCE MANUAL

console to alert the pilot in case of a

YSAS failure.

500NM7301 YSAS Fin Position Indicator

(U.K. Only)

(Ref. Table 1) The 500N helicopters sold in the

United Kingdom come equipped with an

indicating system to alert the pilot in case of a

YSAS failure. Because this is a very limited

option, the parts are not listed in CSP-IPC-4.

The following table is for ordering the major

components of this system.

Table 1. 500NM7301 YSAS Fin Position

Indicator Components

Component

Part Number

Edge light panel

369D26454−27

Indicator

500N7305−3

Vne card set

500N6530−31

369D24506−9

Indicator

PFM Flight Manual Supplement

CSP−520N−1C

369D26454−17

Decal

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CSP-HMI-2

MAINTENANCE MANUAL

NOTAR® ANTI−TORQUE SYSTEM FLIGHT CONTROLS

REMOVAL/INSTALLATION

1. Anti−Torque Flight Controls

3. Forward Directional Control Tube

Replacement

NOTE:

(Ref. Figure 401)

D The NOTAR anti-torque control system

A. Forward Directional Control Tube

must be re-rigged after removal or re

Removal

placement of control rods, linkages and

components or if helicopter operation re

(1). Remove fairings, access covers and

veals a rigging deficiency.

doors necessary to facilitate mainte

D Refer to adjustment and test control rig

nance (Ref. Sec. 53-30-30, Upper Aft

ging, during flight control installation.

Section Fuselage).

(2). Disconnect forward directional control

2. Upper Fuselage Sta. 97.50 (500N) or Sta.

tube from Sta. 97.50 (Sta. 95) bellcrank.

95 (600N) Bellcrank and Support Bracket

(3). Disconnect forward directional control

Replacement

tube from the lever assembly gear

pinion rack Sta. 113.00 splitter and

(Ref. Figure 401)

remove control tube.

A. Sta. 97.50 (500N) or Sta. 95 (600N)

B. Forward Directional Control Tube

Bellcrank and Support Bracket Removal

Installation

(1). Disconnect anti-torque control tube

(1). Forward directional control rod initial

(Sta. 87.50) and Fwd directional control

length is 15.42 inches (39.17 cm),

tube from Sta. 97.50 (Sta. 95) bellcrank.

measured center of rod end to center of

rod end. Install forward directional

control tube on pinion gear rack lever

(2). Remove nuts, washers and bolts from

assembly Sta. 113.00 splitter and on

main rotor mast base support bracket.

Sta. 97.50 (Sta. 95) bellcrank.

Remove bellcrank and support bracket

as an assembly.

(2). Ensure slotted bushings are in place.

Split bushings must protrude 0.010 -

B. Sta. 97.50 (500N) or Sta. 95 (600N)

0.060 inch (0.254 - 1.524 mm) above

Bellcrank and Support Bracket

surface of bellcranks.

Installation

(3). Install washers, bolts and nuts. install

cotter pins and safety wire jamnuts as

(1). Position bellcrank and support bracket

required.

on mast base structure,and install

three bolts, seven washers and three

(4). Install fairings and panels.

nuts. Most forward bolt requires extra

thick washer under head of bolt. Torque

4. Splitter Bungee Spring Replacement

bolt to 80 - 100 inch-pounds (9.04 -

(500N)

11.30 Nm) plus drag torque.

(Ref. Figure 401)

(2). Ensure slotted bushings are in place

and connect anti-torque control tube

Special Tools

and fwd rod end of Fwd directional

(Ref. Section 91-00-00)

control tube to bellcrank and cotter pin.

Item

Nomenclature

Split bushings must protrude 0.010 -

ST601

Rigging pin

0.060 inch (0.254 - 1.524 mm) above

ST602

Spring tension removal tool

surface of bellcrank.

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MAINTENANCE MANUAL

A. Splitter Bungee Spring Removal

(4). Remove nut, washer, link assy. and

spacer and disconnect intermediate

(1). Using two pieces of wood and C-clamp

control tube from gear pinion stud.

or rope, secure pilots pedals in mid

position so they are aligned.

(5). Remove four bolts and washers, and

remove splitter assembly.

(2). Insert rigging pin (ST601) into the

upper hole of bracket assembly and

B. Station 113.00 Splitter Assembly and

through the the slot marked ``M'' in the

Bellcrank Installation

gear pinion rack. (View B).

(1). Position splitter bracket on structure

and install four bolts and washers.

Bungee spring is under ten

WARNING

sion, use care to prevent per

(2). Position intermediate control tube on

sonal injuries or damage to aircraft.

gear pinion stud. Install link, spacer,

washer and nut; install cotter pin.

(3). Disconnect spring from links, either aft

or fwd., using a spring expansion tool

(3). During installation of walking lever

(ST602).

and bracket, align the index marks

together and install pivot bolt, spacer,

B. Splitter Bungee Spring Installation

washers and nut and torque to 50 - 60

inch-pounds (5.65 - 6.78 Nm).

(1). Insert rigging pin (ST601) into the

Ensure bushings and bearings are in

upper hole of bracket assembly and

place; install cotter pin.

through the the slot marked ``M'' in the

gear pinion rack Sta. 113.00 splitter.

(4). Install forward cable assembly rodend

and fwd directional control tube rodend.

(2). With a spring expansion tool (ST602),

Ensure bushings are in place. Torque

expand the spring the amount neces

nuts and install cotter pin.

sary to secure the spring to the forward

and aft links.

(5).

500N Only: Install splitter bungee

spring.

(3). Remove rigging pin.

6. Intermediate Control Tube Replacement

5. Upper Fuselage Station 113.00 Splitter

Assembly and Bellcrank Replacement

(Ref. Figure 402)

A. Intermediate Control Tube Removal

A. Station 113.00 Splitter Assembly and

(1).

500N Only: Remove splitter bungee

Bellcrank Removal

spring from Sta. 113.00 splitter assem

bly pinion gear (Ref. Splitter Bungee

(1).

500N Only: Remove splitter bungee

Spring Replacement (500N)).

spring from Sta. 113.00 splitter assem

bly pinion gear (Ref. Splitter Bungee

(2). Disconnect intermediate control tube

Spring Replacement (500N)).

from gear pinion stud by removing nut,

washer, link and spacer.

(2). Disconnect forward cable assembly

rodend and rodend of forward direction

(3). Disconnect aft end of intermediate

al control tube from walking lever.

control tube at Sta. 137.50 bellcrank by

depressing pin in head of bolt to release

NOTE: Note relationship of index marks on

locking ball while removing nut. With

splitter assembly.

pin still depressed, remove bolt.

(3). Align index marks on gear teeth.

(4). Remove control tube boot ty-strap, and

Remove walking lever from splitter

move control tube carefully forward

bracket by removing nut, pivot bolt,

through boot, support tube at plenum

washers and spacer.

chamber inlet.

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B. Intermediate Control Tube Installation

7. Station 137.50 Support Bracket and

Bellcrank Replacement

(1). Carefully feed intermediate control

(Ref. Figure 402)

tube through boot if installed and

forward air inlet to bellcrank at Sta.

A. Station 137.50 Support Bracket and

137.50.

Bellcrank Removal

(2). Connect control tube and check that

(1). Disconnect intermediate control tube

bushings are in place.

from upper end of Sta. 137.50 bellcrank

by depressing pin in head of bolt to

(3). Install impedance bolt as follows:

disengage and release locking ball and

removing nut. With pin still depressed,

NOTE: Install bolt-head up, nut facing down.

remove bolt.

(2). Disconnect link assembly at clevis,

(a). Depress pin in head of bolt to install

remove bolt in same manner as in

bolt though clevis assembly.

previous step.

NOTE: In the following step, pin is to remain

(3). Remove four support bracket assembly

depressed while nut is torqued.

bolts from fan transmission support.

(b). While pin is depressed, install nut

(4). Bellcrank and bracket assembly may be

and torque to 40 - 50 inch-pounds

separated by removing bolt.

(4.52 - 5.65 Nm).

B. Station 137.50 Support Bracket and

Bellcrank Installation

(c). Release pin and retorque nut to 75 -

90 inch-pounds (8.47 - 10.17 Nm)

NOTE: It is recommended to assemble link and

to ensure engagement of locking balls

bracket assembly to bellcrank before install

with nut.

ing bracket assembly on fan transmission

support bracket.

NOTE: Pin must be in the released position

(1). Reassemble bellcrank and bracket

(flush with bolt head) and bolt must pro

assembly if necessary.

trude past the nut for proper installation.

(2). Install impedance bolt as follows:

(d). Apply torque stripe.

(a). Depress pin in head of bolt to install

(4). Install alternate NAS6204-11D bolt

bolt through bracket and bellcrank.

and MS17826-4 nut as follows:

NOTE: In the following step, pin is to remain

depressed while nut is torqued.

(a). Install bolt, with one AN960KD416L

washer through clevis assembly.

(b). Install nut and torque to 100 - 120

inch-pounds (11.30 - 13.56 Nm).

(b). Install AN960KD416L washer and

(c). Release pin and torque nut to 200 -

nut and torque to 20 - 40 inch-

225 inch-pounds (22.60 - 25.42

pounds (2.26 - 4.52 Nm); install

Nm) to insure engagement of locking

MS24665-134 cotter pin.

ball with nut.

(5). Position rubber boot in place. Secure

NOTE: Pin must be in the released position

boot at support tube with nylon strap,

(flush with bolt head) and bolt must pro

then clamp directional control pedals in

trude past the nut for proper installation.

neutral, set free length of bellows

portion of boot at approximately 5.5

(d). Apply torque stripe.

inches (13.97 cm) and secure end to

(3). Install alternate NAS6206-29D bolt

control tube with nylon strap.

and MS17826-6 nut as follows:

(6).

500N Only: Install splitter bungee

(a). Install bolt, with one AN960KD616L

spring.

washer through clevis assembly.

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(b). Install AN960KD616L washer and

NOTE: The Fan Pitch Control Tube can be re

nut and torque to 95 - 110 inch-

moved in either one of the following steps.

pounds (10.73 - 12.43 Nm); install

The fan assembly pitch bearing slider, pitch

MS24665-285 cotter pin.

bearing retainer, pitch plate bearings and

bearing retainer nut with aft control tube

(4). Install lower bolt at link assembly and

can be removed as a unit or individually.

bellcrank clevis, and upper bolt inter

Use extreme care do not damage parts.

mediate control tube Sta. 137.50

(1) Remove locking wire and remove nut and

bellcrank bolts as follows:

lock washer from fan pitch control tube.

NOTE: Install bolt-head up, nut facing down.

Remove locking wire and remove three

bolts and washers from pitch bearing re

(a). Depress pin in head of bolt to install

tainer housing. Pitch bearing slider, pitch

bolt through clevis end of bellcrank.

plate bearings and, bearing retainer nut

with aft control tube can be removed as a

NOTE: In the following step, pin is to remain

unit.

depressed while nut is torqued.

(2) Remove locking wire and remove six pitch

(b). While pin is depressed, install nut

bearing housing assembly bolts. Remove

and torque to 40 - 50 inch-pounds

pitch bearing retainer housing assembly

(4.52 - 5.65 Nm).

as a unit.

(c). Release pin and retorque nut to 75 -

B. Fan Pitch Control Tube Installation

90 inch-pounds (8.47 - 10.17 Nm)

to ensure engagement of locking balls

NOTE:

with nut.

D Refer to Fan Pitch Control Rigging during

installation.

NOTE: Pin must be in the released position

(flush with bolt head) and bolt must pro

D Before installing fan pitch control tube,

trude past the nut for proper installation.

perform Fan Pitch Control Tube Inspec

tion.

(d). Apply torque stripe.

(1). Install the aft control tube.

(5). Install alternate NAS6204-11D bolt

and MS17826-4 nut as follows:

(2). Install convoluted boot on fan gearbox

or clevis.

(a). Install bolt, with one AN960KD416L

washer through clevis assembly.

NOTE: In the following step, clevis should be

bottomed into control tube, approximately

(b). Install AN960KD416L washer and

one thread showing after engagement.

nut and torque to 20 - 40 inch-

pounds (2.26 - 4.52 Nm); install

(3). Install clevis assembly on aft control

MS24665-134 cotter pin.

tube. Ensure that clevis has full thread

engagement on control tube.

(6). Install four support bracket assembly

bolts and washers to fan transmission

(4). Ensure locking washer tang tip is in

support. Torque bolts to 70 - 90

slot. Tighten jam nut against locking

inch-pounds (7.91 - 10.17 Nm);

washer and safety wire from lock to

safety wire bolts.

nut. Ensure safety wire pigtail is on the

nut.

8. Fan Pitch Control Tube Replacement

(5). Install floating bushing in clevis.

A. Fan Pitch Control Tube Removal

(6). Install bolt, bolthead on floating

(1). Remove tail boom fairing and tail boom.

bushing side of clevis, through clevis

and link assembly as follows:

(2). Remove bolt and clevis assembly at Sta.

137.50 bellcrank. Remove convoluted

(a). Depress pin in head of bolt to install

boot from fan gearbox.

bolt through clevis end of bellcrank.

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NOTE: In the following step, pin is to remain

of three threads protruding beyond the

depressed while nut is torqued.

face of the jam nut.

(b). While pin is depressed, install nut

(13). Install two lockwires on jamnut and

and torque to 40 - 50 inch-pounds

lockwasher.

(4.52 - 5.65 Nm).

NOTE:

After safety wiring nut and bolts, rotate

(c). Release pin and retorque nut to 75 -

fan and ensure that safety wires do not have

90 inch-pounds (8.47 - 10.17 Nm)

interference with each other on rotation.

to ensure engagement of locking balls

(14). Install tail boom (Ref. Sec. 53-40-30).

with nut.

NOTE: Pin must be in the released position

9. Forward Cable Assembly Replacement

(flush with bolt head) and bolt must pro

(Ref. Figure 402)

trude past the nut for proper installation.

A. Forward Cable Assembly Removal

(d). Apply torque stripe.

To prevent damage to the engine

(7). Install alternate NAS6204-11D bolt

CAUTION

install F.O.D. cover over engine

and MS17826-4 nut as follows:

air inlet.

(a). Install bolt, with one AN960KD416L

washer through clevis assembly.

(1).

Remove fairings, access doors and

panels necessary to facilitate mainte

(b). Install AN960KD416L washer and

nance (Ref. Sec. 53-30-30).

nut and torque to 20 - 40 inch-

pounds (2.26 - 4.52 Nm); install

(2).

Remove tailboom fairing.

MS24665-134 cotter pin.

(3).

Disconnect the aft end of the anti-

NOTE: Before installing fan pitch slider, per

torque control cable by turning outside

form Fan Pitch Slider Inspection.

collar sleeve counter-clockwise and

back to expose the inner cable.

(8). Install pitch bearing slider and bearing

retainer per rigging instructions.

(4).

Apply sufficient right pedal to expose

inner cables.

(9). Install pitch bearing and pitch bearing

retainer housing using three bolts and

(5).

Without bending cable, slide male

washers. Torque bolts to 70 - 80

connector out of female connector.

inch-pounds (7.91 - 9.04 Nm); safety

(6).

Disconnect cable assembly forward

wire bolts.

rodend from Sta. 113.00 splitter

(10). Install lockwasher so that the face of

assembly outboard bellcrank clevis.

the tang aligns with the tube assembly

(7).

Loosen jam nut at rodend and remove

keyway, and the lockwasher aligns with

rodend from cable; remove jam nut.

one of the six slots in the face of the

bearing retainer.

(8).

Remove safety wire, jam nuts and

washers from cable assembly support

(11). Install jamnut on aft control tube.

bracket, remove by pulling or sliding

(12). Torque nut to 95 -110 inch-pounds

cable assy. thru conduit and support

(10.73 - 12.43 Nm) leaving a minimum

bracket.

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B. Forward Cable Assembly Installation

(b). Without bending cable, insert inner

male connector into inner female

connector and ensure they are

Consumable Materials

properly engaged together.

(Ref. Section 91-00-00)

Item

Nomenclature

(c). Slide outside cable collar over

forward cable to engage locking

CM702

Lockwire CRES

device and turn clockwise until fully

locked.

Before installation of cable, in

CAUTION

spect cable (Ref. Forward and

(12). Verify rigging of cable assembly from

Center Cable Assembly Inspection).

Sta. 113.00 splitter assembly (Ref.

Adjustment/Test).

(1). Install one jam nut and washer on cable

and insert cable assembly through

(13). Install fairings, access doors and panels

support bracket and conduit.

removed for installation.

(2). Install washer and one jam nut on cable

10. Center Cable Assembly Replacement

forward side of support bracket.

(Ref. Figure 402)

(3). Ensure that the threaded portion is

A. Center Cable Assembly Removal

centered in the support bracket.

(1).

Remove rotating thruster cone (Ref.

NOTE: When tightening cable jamnuts, ensure

Sec. 53-40-30).

smooth action of cable and alignment of

cable hex end into cable socket.

(2).

Remove stationary thruster cone (Ref.

Sec. 53-40-30).

(4). Ensure cable hex end and cable socket

are aligned to ensure smooth action.

(3).

Remove cotter pin, nut, washers and

bolt from clevis end of control rod

(5). Slide cable in and out to ensure there is

double rodend.

no binding and tighten jamnuts.

(4).

Disconnect cable assembly double rod

(6). Slide cable in and out again to ensure

end bearing from center tailboom

there is no binding. If cable slides

bellcrank.

smoothly, safety jamnuts (CM702).

(5).

Remove double rod end from cable

(7). Install rodend bearing with locking

assembly.

device and jamnut.

(6).

Remove tailboom fairing.

(8). Ensure that threads protrude past

witness hole. Tighten jamnut and

(7).

Disconnect the forward end of the

safety wire nuts.

anti-torque control cable by turning

forward cable outside collar sleeve

(9). Connect cable assembly forward rodend

counter-clockwise and back to expose

to Sta. 113.00 splitter assembly out

the inner cable.

board bellcrank clevis.

(8).

Apply sufficient right pedal to expose

(10). Torque nut and install cotter pin.

inner cables.

(11). Reconnect forward and center control

(9).

Without bending cable, slide male

cable couplings.

connector out of female connector.

Failure to properly connect

(10).

Disconnect cable assembly forward

WARNING

thruster cables could result

rodend from Sta. 113.00 splitter

in uncoupling during flight and loss of

assembly outboard bellcrank clevis.

anti-torque authority.

(11).

Remove safety wire and aft jamnut

(a). Apply sufficient right pedal to expose

from cable assembly support bracket.

inner cable female connector.

Cable assembly can be removed by

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MAINTENANCE MANUAL

sliding or pulling cable assembly

Failure to properly connect

WARNING

through support bracket and conduit

thruster cables could result

and through grommet.

in uncoupling during flight and loss of

anti-torque authority.

B. Center Cable Assembly Installation

(a). Apply sufficient right pedal to expose

inner cable female connector.

Before installation of cable, in

CAUTION

spect cable (Ref. Forward and

(b). Without bending cable, insert inner

Center Cable Assembly Inspection).

male connector into inner female

connector and ensure they are

(1). Install one jam nut and washer on cable

properly engaged together.

and route cable assembly thru conduit

(c). Slide outside cable collar over

of tailboom and thru support bracket.

forward cable to engage locking

device and turn clockwise until fully

(2). Install washer and jamnut on cable aft

locked.

side of support bracket.

(11). Verify rigging of cable assembly from

(3). Ensure that the threaded portion is

Sta. 113.00 splitter assembly to vertical

centered in the support bracket.

stabilizers is correct.

(12). Install stationary thruster cone.

NOTE: When tightening cable jamnuts, ensure

smooth action of cable and alignment of

(13). Install rotating thruster cone.

cable hex end into cable socket.

11. Aft Control Rod Assembly Replacement

(4). Ensure cable hex end and cable socket

(Ref. Figure 402)

are aligned to ensure smooth action.

A. Aft Control Rod Assembly Removal

(5). Slide cable in and out to ensure there is

(1). Remove thruster cone (Ref. Sec.

no binding and tighten jamnuts.

53-40-30).

(6). Slide cable in and out again to ensure

(2). Remove stationary thruster cone (Ref.

there is no binding. If cable slides

Sec. 53-40-30).

smoothly, safety jamnuts (CM702).

(3). Remove cotter pin, nut and washer

from sector input shaft.

(7). Install double rodend bearing with

locking device and jamnut.

(4). Remove pan cover.

(5). Remove cotter pin, nut, washers and

(8). Ensure that threads protrude past

bolt from clevis end of control rod at

witness hole. Tighten jamnut and

double rodend bearing of tailboom

safety wire nuts.

center cable assembly.

NOTE: The split bushing is installed at the top

(6). Remove and discard lockwire and then

of bellcrank. A minimum of 0.010 inch

remove control rod bolt from sector

(0.254 mm) and a maximum of 0.060 inch

assembly.

(1.524 mm) split bushing protrusion re

quired above surface.

(7). Remove control rod.

B. Aft Control Rod Assembly Installation

(9). Install double rodend bearing and

forward bearing to bellcrank with bolt,

washers and nut. Tighten nut and

Consumable Materials

install cotter pin.

(Ref. Section 91-00-00)

Item

Nomenclature

(10). Reconnect forward and center control

CM702

Lockwire CRES

cable couplings.

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MAINTENANCE MANUAL

NOTE: Split bushing is installed at the top,

(6). Remove control rod bolt from sector

shoulder bushing is installed at bottom. A

assembly and lift sector assembly from

minimum of 0.010 inch (0.254 mm) and

shaft.

maximum of 0.060 inch (1.524 mm) split

(7). Remove clevis pins from sector assem

bushing protrusion required above surface.

bly and remove cables.

(1).

Connect thruster control rod clevis end

B. Sector Assembly and Control Cable

to double rod end aft bearing of center

Installation

cable assembly.

(2).

Install washer and bushing on bolt and

Consumable Materials

then insert through rod end into sector

(Ref. Section 91-00-00)

assembly.

Item

Nomenclature

(3).

Torque bolt to 30 - 40 inch-pounds

CM702

Lockwire CRES

(3.39 - 4.52 Nm) and install safety wire

(CM702).

(1). Position the cable assembly around

thruster sector bellcrank, install cable

(4).

Install bushings, bolt, washer and nut;

clevis pins and cotter pins.

Torque nut to 30 - 40 inch-pounds

(3.39 - 4.52 Nm) and install cotter pin.

(2). Install sector bellcrank on input shaft.

(5).

Install pan cover.

(3). Connect sector assembly aft control rod

to clevis.

(6).

Install washer and nut on sector input

shaft; torque nut to 95 - 110 inch-

(a). Install washer and bushing on bolt

pounds (10.73 - 12.43 Nm) and install

and then insert through rod end into

cotter pin.

sector assembly.

(7).

Install stationary thruster cone.

(b). Torque bolt to 30 - 40 inch-pounds

(3.39 - 4.52 Nm) and install safety

(8).

Install rotating thruster cone.

wire (CM702).

12. Sector Assembly and Control Cable

(4). Install bushing, washer on sector input

Replacement

shaft.

(5). Install pan cover.

(Ref. Figure 401)

(6). Install washer and nut on sector input

A. Sector Assembly and Control Cable

shaft; torque nut to 95 - 110 inch-

Removal

pounds (10.73 - 12.43 Nm) and install

(1). Remove rotating thruster cone (Ref.

cotter pin.

Sec. 53-40-30).

(7). Install rotating thruster cone.

NOTE: Removed safety clips from turnbuckles

(8). Perform a rigging check.

are not to be reused.

13. Drum Assembly and Idler Pulley

(2). Disconnect cables from turnbuckles in

Replacement

access hole provided (top of stationary

cone).

(Ref. Figure 401)

(3). Remove cotter pin, nut and washers

A. Drum Assembly and Idler Pulley Removal

from sector input shaft.

(1). Remove rotating thruster cone (Ref.

(4). Remove pan cover.

Sec. 53-40-30).

(5). Remove washer and bushing under pan

NOTE: Removed safety clips from turnbuckles

cover from sector bellcrank input shaft.

are not to be reused.

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MAINTENANCE MANUAL

(2). Disconnect cables from turnbuckles in

(2). Install drum assembly on shaft and

access hole provided (top of stationary

install guard pins.

cone).

(3). Install HS306-233H flat washer

against the bearing.

(3). Remove cotter pin, nut and two wash

ers, remove drum assembly from shaft.

(4). Install washer and nut; torque nut to

160 - 190 inch-pounds (18.08 - 21.47

(4). Remove guard pins to remove cable

Nm) and install cotter pin.

assemblies.

(5). Install turnbuckles and cables.

B. Drum Assembly and Idler Pulley

(6). Perform a rigging check.

Installation (500N)

(7). Install rotating thruster cone.

NOTE: The long cable is 23.07 inches (58.60

cm) and is installed on the aft cable guide of

14. Anti−Torque Pedal Friction Replacement

the drum, or right side, up and around the

(Ref. Figure 403)

right idler pulley. The short cable is 22.82

inches (57.96 cm) long and is installed on

A. Anti−Torque Pedal Friction Removal

the fwd cable guide of the drum, or left side,

(1). Remove bolt, washer and bushing from

up and round the left idler pulley.

console support bracket.

(1). Install cables on drum assembly.

(2). Remove nut and washers, remove

spring, retainer, spring and friction

(2). Install drum assembly on shaft and

disc, and link.

install guard pins.

(3). Remove brace and clamp arm assembly

(3). Install HS306-233H flat washer

from anti-torque tube assembly.

against the bearing.

B. Anti−Torque Pedal Friction Installation

(4). Install washer and nut; torque nut to

(1). Using two pieces of wood and C-clamp

160 - 190 inch-pounds (18.08 - 21.47

or rope, secure pilot's pedals in mid

Nm) and install cotter pin.

position so they are aligned within 0.50

inch (1.27 cm) of each other.

(5). Install turnbuckles and cables.

(2). Install washer, bolt, bushing, and link

(6). Perform a rigging check.

assembly to bracket assembly on

instrument console.

(7). Install rotating thruster cone.

(3). Install brace and clamp arm assembly

C. Drum Assembly and Idler Pulley

to anti-torque tube assembly.

Installation (600N)

(4). Install friction disc, link, retainer and

spring, install washer (shim washers if

NOTE: The long cable is 23.76 inches (60.35

required) and nut.

cm) long and is installed on the aft cable

guide of the drum, or right side, over and

(5). Torque brace and arm assembly bolts

around the left idler pulley. The short cable

30 - 35 inch-pounds (3.39 - 3.95

is 23.51 inches (59.72 cm) long and is in

Nm). Torque nut against washer to

stalled on the fwd cable guide of the drum,

obtain a pedal friction of 5 - 8 pounds

or left side, over and round the right idler

(2.27 - 3.63 kg).

pulley.

15. Anti−Torque Pedal Assembly

(1). Install cables on drum assembly as

Replacement

follows:

(Ref. Figure 403)

(a). Install left cable on forward groove of

A. Anti−Torque Pedal Assembly Removal

drum and cross over to right pulley.

(1). Pull two hinge pins from pilot's com

(b). Install right cable on aft groove of

partment floor access door hinges and

drum and cross over to left pulley.

remove door.

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MAINTENANCE MANUAL

STA. 97.50 BELLCRANK

STA. 97.50

(TUNNEL-ROUTED)

CONTROL ROD

CONTROLS SUPPORT

BRACKET

ANTI-TORQUE PEDAL

INITIAL CONTROL ROD LENGTH

FRICTION

- BEFORE RIG

SPRING FITTING

CONTROL

DIMENSION L

AFT EYEBOLT

TAIL ROTOR IDLER

ROD

INCHES (CM)

STA. 63.00

BELLCRANK

TUNNEL-ROUTED

57.95

(147.193)

BUNGEE

FLOOR-ROUTED

30.06

(76.3524)

SPRING

NOTE 2

FORWARD EYEBOLT

RIVET

NOTE 1

FLOOR-ROUTED

CONTROL ROD

MAXIMUM ALLOWABLE LOOSENESS

NOTE 2

0.040 IN. (1.016 MM)

NOTE 3

TORQUE TUBE

BUSHING ASSY

(NOTE 4)

* TORQUE TUBE BRACKET

NOTE 1

NOTE 3

(NOTE 5)

CONTROL ROD FITTING

NOTE 1

WASHER

NOTE 4

NOTE 1

* LEFT PEDAL

BEARING

STOP BOLT

* RIGHT PEDAL

JAMNUT

NOTE 2

NOTE 3

NOTE 1

* PEDAL ARM

NOTE 1

* PEDAL BRACKET

BUSHING

* PEDAL ARM

(TEFLON-LINED)

NOTE 4

NOTE 2

BUSHING

(TEFLON-LINED)

NOTES:

SHIM BETWEEN BRACKET AND BULKHEAD WITH AN960PD416

BUSHING ASSY

LINK

AND/OR -416L WASHERS AS REQUIRED FOR ALIGNMENT WITHIN

(NOTE 4)

NOTE 2

0.010 IN. (0.254 MM).

EDGE OF BUSHING MUST PROTRUDE A MINIMUM OF 0.010 IN.

NOTE 2

(0.254 MM) TO A MAXIMUM OF 0.060 IN. (1.524 MM) ABOVE OUTSIDE

BEARING

SURFACE OF PART AFTER NUT IS TIGHTENED.

BELLCRANK

DIRECTION OF BOLTS IS OPTIONAL.

ADJUSTABLE BUSHINGS MUST HAVE A MINIMUM PROTRUSION OF

0.002 IN. (0.051 MM) AT EACH END.

INSTALLED WITH BEARING RECESS FACING FITTING.

ASTERISK (*) INDICATES PART THAT MAY BE EITHER MAGNESIUM OR

ALUMINUM ALLOY. FOR ALLOY IDENTIFICATION AND CORROSION

CONTROL REF. SEC. 20-40-00.

G67-2001-3

Figure 403. Pedal Installation (Sheet 1 of 2)

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MAINTENANCE MANUAL

RIGHT POSITION

STOP BOLT

ANTI-TORQUE PEDALS

(2 EACH)

NOTE 1

NOTE 2

JAMNUT

ADJUSTABLE BUSHING

ASSEMBLY (NOTE 4)

NOTE 3

TORQUE TUBE

SLOTTED BUSHING

(TYPICAL) (NOTE 2)

SLEEVE

TORQUE TUBE

ADJUSTABLE BUSHING

ASSEMBLY (NOTE 4)

G67-2001-4

Figure 403. Pedal Installation (Sheet 2 of 2)

(2). Remove access panel from each side of

simplify torque tube alignment during

instruction panel lower support struc

reinstallation.

ture.

(8). Remove four nuts, eight washers, any

shims washers and four bolts that

(3). Remove battery (Ref. Sec. 96-00-00).

secure pedal bracket to bulkhead.

(4). Remove pins securing pedals to pedal

(9). Remove control pedal installation. Keep

arms and remove pedals.

shim washer selection with bracket for

reinstallation.

(5). Remove pedal friction mechanism.

B. Anti−Torque Pedal Assembly Installation

(6). Remove cotter pin, nut, two washers

(1). Install pedal bracket with four bolts,

and bolt that connect floor-routed

eight washers and four nuts.

control rod to torque tube fitting.

(2). Add shim washers as required at pedal

(7). Remove two nuts, four washers, any

bracket attachment points to keep

shim washers and two bolts that secure

centerline alignment of pedal bracket

torque tube bracket to bulkhead. Keep

bearings within 0.010 inch. Correct

shim washer selection with bracket to

alignment is indicated by free rotation

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MAINTENANCE MANUAL

al movement of torque tube after nuts

NOTE: Observed and note position of vertical

are torqued with no evidence of binding.

stabilizer bellcrank for reinstallation pur

poses.

(3).

Position torque tube bracket over

(6). Remove vertical stabilizer torque tube

mating holes in bulkhead and check

(Ref. Sec. 53-50-30, Vertical Stabilizer

alignment with bulkhead.

Torque Tube and/or Bushing Replace

(4).

Add shim washers as required at

ment).

bracket attachment points to maintain

(7). Disconnect electrical connector from

bearing alignment established in step

actuator.

(2). above. Install two bolts, four

washers and two nuts.

(8). Disconnect S.A.S. actuator from control

rod.

(5).

Check that slotted bushing is in place,

(9). Remove bolts from actuator support

install floor-routed control rod in

bracket and carefully slide actuator out

torque tube fitting and install bolt, two

of access hole.

washers and nut; install cotter pin. A

minimum of 0.010 inch (0.254 mm) and

B. S.A.S. Actuator Installation

a maximum of 0.060 inch (1.524 mm)

split bushing protrusion required above

NOTE: Whenever S.A.S. actuator or control

surface.

tube is replaced, S.A.S. rigging must be per

formed.

(6).

Install anti-toque pedal friction

(1). Slide actuator through access panel and

mechanism.

attach actuator to support bracket.

(7).

Check rigging of pedal assembly

(2). Install vertical stabilizer torque tube

controls and pedal-to-canopy clear

(Ref. Sec. 53-50-30, Vertical Stabilizer

ance. Pedals should clear windows by a

Torque Tube Replacement).

minimum of 0.020 inch (0.508 mm) with

20 pounds (9.0718 Kg) of force applied.

(3). Connect actuator control tube to

vertical stabilizer torque tube bell

16. Stability Augmentation System (S.A.S.)

crank. Torque nut to 30 - 40 inch-

Actuator Replacement

pounds (3.39 - 4.52 Nm) and install

cotter pin.

(Ref. Figure 505)

NOTE: Care should be observed to position ver

tical stabilizer bellcrank in the same posi

A. S.A.S. Actuator Removal

tion as removed.

(1). Disconnect electrical power from

(4). Reinstall upper and lower R/H vertical

aircraft. Ensure that battery power is

stabilizers (Ref. Sec. 53-50-30, Vertical

disconnect.

Stabilizer Replacement).

(2). Remove horizontal stabilizer center

(5). Reconnect electrical connector to

access panels and R/H end cap access

actuator.

cover.

(6). Perform S.A.S. actuator rigging check

(Ref. Stability Augmentation System

(3). Remove upper and lower R/H vertical

Rigging Instructions).

stabilizers (Ref. Sec. 53-50-30, Vertical

Stabilizer Replacement).

(7). Install access panels.

(4). Disconnect actuator control tube from

17. S.A.S. Rate Gyro and Electronic Control

vertical stabilizer torque tube bell

Box (Computer) Replacement

crank.

Access to the rate gyro and electronic control

(5). Remove R/H vertical stabilizer torque

box (computer) is through the passenger

tube bellcrank.

compartment footwell access panels.

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CSP-HMI-2

MD Helicopters, Inc.

MAINTENANCE MANUAL

The units are mounted on a rack under the

(2). Disconnect and remove electrical plug.

pilot's seat structure against the seat structure

(3). Remove mounting hardware.

forward panel.

(4). Carefully remove component from rack.

The 500N has the components mounted

approximately 12 inches (30.48 cm) to the

B. S.A.S. Rate Gyro and Electronic Control

right of centerline.

Box (Computer) Installation

The 600N has the components mounted

(1). Install component on rack.

approximately 12 inches (30.48 cm) to the left

of centerline.

(2). Reinstall mounting hardware. Torque

screws to 12 - 15 inch-pounds (1.36 -

A. S.A.S. Rate Gyro and Electronic Control

1.69 Nm) plus drag torque.

Box (Computer) Removal

(3). Connect electrical plug.

(1). Remove appropriate passenger

compartment footwell fairing (Ref. Sec.

(4). Reinstall passenger compartment

52-50-00).

footwell fairing (Ref. Sec. 52-50-00).

Page 416

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CSP-HMI-2

MAINTENANCE MANUAL

NOTAR® ANTI−TORQUE SYSTEM FLIGHT CONTROLS

ADJUSTMENT/TEST

1. Directional Controls Rigging

(3). Assemble the pitch plate control

bearing into slider and attach the

NOTE:

bearing retainer plate using three bolts

and three washers.

D On the 500N, directional control rigging

is to be accomplished with the (Sta.

(4). Torque bolts to 70 - 80 inch-pounds

113.00) spring on the splitter assembly

(7.91 - 9.04 Nm) and safety (CM702).

disconnected.

D The NOTAR control system must be re-

NOTE: Every 60° turn on bearing retainer is

rigged after replacement of control rods,

equivalent to 0.6 degree change in fan pitch

linkages, and components or if helicopter

angle.

operation reveals a rigging deficiency.

(5). Using the TICK marks on the fan blade

2. Fan Pitch Control Rigging

assembly and on hub housing to

determine blade pitch angle, adjust

(Ref. Figure 501)

bearing retainer to obtain a fan blade

pitch angle of 26 ±1° (View D).

Consumable Materials

NOTE:

(Ref. Section 91−00−00)

Item

Nomenclature

D The aft control tube keyway should be in

stalled at the 12 O'clock position for ease

CM702

Lockwire CRES

of installation.

D Ensure that one of the six slots in the face

Special Tools

of the bearing retainer aligns with fan

(Ref. Section 91−00−00)

pitch-aft control tube key way (View C).

Item

Nomenclature

ST601

Rigging pin

(6).

Install lockwasher so that the face of

the lockwasher aligns with one of six

slots of the bearing retainer.

NOTE: Fan Pitch Control Rigging shall be ac

complished with the tailboom and engine air

(7).

Install jam nut, torque nut to 95 - 110

inlet fairings removed.

inch-pounds (10.73 - 12.43 Nm)

leaving a minimum of three threads

(1). Position Sta. 113.00 splitter assembly

protruding beyond the face of the jam

pinion gear so the rigging slot aligns

nut.

with lower rigging hole in the bracket

assembly; Insert the rigging pin

(8).

Check tick marks on fan blade assem

(ST601) (View A).

bly and hub housing, ensure that fan

pitch angle is 26 ±1°. If blade pitch is 26

(2). Adjust the bearing retainer so the

±1°, proceed to step (9). If not, remove

flange of bearing retainer is screwed in

jamnut and lockwasher and return to

on the tube assembly until it just

steps (5).

touches the shoulder of the fan pitch-

aft control tube (View B).

(9).

Safety wire (CM702) nut and lockwash

NOTE: A gap of 0.015-0.025 inch (0.381-0.635

er (2 places required).

mm) between pitch bearing housing and

bearing retainer plate must exist to ensure

(10).

Rotate fan to ensure the safety wire

proper clamp-up.

does not interfere.

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MD Helicopters, Inc.

MAINTENANCE MANUAL

UPPER RIGGING

HOLE

FWD CONTROL

CABLE

SEVENTEEN TO SEVENTY−SEVEN

BRACKET

DEGREES AT 5° INCREMENTS

ASSY

PINION GEAR

LOWER RIGGING

HOLE

500N9901

TICK MARKS

RIGGING TOOL

26° ±1° FAN C/L

FAN HUB ASSY

17°

SPLITTER ASSEMBLY

77°

RIGGING LOCATION

FAN BLADE ASSY

BEARING RETAINER

TICK MARK LOCATION

ASSEMBLY

ON FAN ASSEMBLY

PITCH PLATE

CONTROL BEARING

ONE OF

BEARING

SIX SLOTS

RETAINER

FAN PITCH

CONTROL TUBE

SLIDER

FAN PITCH CONTROL

BEARING RETAINER

TUBE ASSY

KEYWAY TUBE

LOCATION

BEARING RETAINER SLOT

AND KEYWAY ALIGNMENT

G67−2010

Figure 501. Fan Pitch Control Rigging

Page 502

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MD Helicopters, Inc.

CSP-HMI-2

MAINTENANCE MANUAL

NOTE:

they are aligned (View A). Maximum

misalignment between pedals shall be

D If the required adjustment of bearing re

0.50 inch (1.27 mm).

tainer, lockwasher and jamnut cannot be

achieved, adjust the intermediate control

NOTE: Do not adjust the control rod beyond the

tube to meet requirements of specifica

witness hole. Do not tighten the locking

tions in steps (5). thru (10).

jamnut until after final adjustment.

D Do not adjust the control rodend beyond

the witness hole. Do not tighten jam nut

(3). Anti-torque idler bellcrank position to

until after final adjustment.

be checked as follows:

(11). Remove rigging pin.

(a). Position pilot's foot pedals in neutral

and floor-routed control rod length

(12). Fan Pitch Control Rigging shall

(initial control rod length is 30.06

produce the following results:

inches (76.35 cm) before rigging).

(a).

500N:

(b). Adjust floor-routed control rod so

1). Full left pedal, 69 - 73 degrees.

that centerline of bellcrank arm is

90° ±2 degrees to Sta. 78.50 canted

2). Full right pedal, 50 - 54 degrees.

bulkhead (View B).

(b).

600N;

(c). Sta. 97.50 bellcrank: Adjust the

tunnel-routed control rod so the

1). Full left pedal, 71 - 75 degrees.

centerline of the tunnel-routed

2). Full right pedal, 52 - 56 degrees.

control rod attach bolt in the transfer

bellcrank is 4.21 - 4.39 inches (10.69

NOTE: On the 600N helicopter, the pedal po

- 11.15 cm) above mast base struc

tentiometer rigging must be checked any

ture (View C).

time the anti-torque system has been ad

justed.

(4). Check witness holes for proper thread

engagement.

3. Pilot Pedal Rigging

(5). Tighten jamnuts and safetywire

(Ref. Figure 502)

(CM702) as required.

(6). Adjust rodends on the forward control

Consumable Materials

tube so the rigging pin can be inserted

(Ref. Section 91−00−00)

into the bracket assembly upper hole

Item

Nomenclature

and through the slot marked ``M” in the

CM702

Lockwire CRES

gear pinion rack Sta. 113.00 splitter

assembly (View D).

NOTE: Directional control rigging shall be ac

(7). Remove rigging pin and remove

complished with the (Sta.113) splitter

clamping device from foot pedal arms.

spring assembly disconnected (500N) and

the fan pitch control rigging complete.

Use care when actuating pedals

CAUTION

(1). Remove left-hand air inlet fairing to

to avoid damaging tool or wind

facilitate pedal rigging (Ref. Sec.

shield.

53-30-30).

(8). Loosen jamnuts on pedal stop-bolts

Remove pilot's pedals and copi

(View A).

CAUTION

lot's (if installed) to prevent pos

sible contact with lower windshield during

(9). Screw in pedal stop-bolts approximate

rigging sequence.

ly one-half inch (12.7 mm).

(2). Using two pieces of wood and C-clamp

(10). Adjust left-hand stop-bolt in the pilot's

or rope, secure pilot's foot pedal arms so

pedal support.

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CSP-HMI-2

MD Helicopters, Inc.

MAINTENANCE MANUAL

MID PEDAL

FWD CONTROL

RIGGING HOLE

TUBE

FWD. CABLE

ASSEMBLY

FULL RIGH

RIGGING H

FULL LEFT PEDAL

RIGGING HOLE

RIGGING PIN

LOWER

STA 97.50

RIGGING HOLE

BELLCRANK

FULL LEFT PEDAL AND FULL RIGHT PEDAL

MIDTRAVEL RIGGING LOCATIONS

STA 113.00 SPLITTER ASSEMBLY

STA 78.50 (TUNNEL

4.30

MAST BASE

ROUTED CONTROL ROD)

+0.090

−

STA 78.50 (TUNNEL

ROUTED CONTROL ROD)

CONTROLS SUPPORT

BRACKET

0.50 INCH MAXIMUM

MISALIGNMENT

BETWEEN PEDALS

CLAMPING BLOCKS

90°+ 2°

STA 78.50

−

CANTED BULKHEAD

RIGHT STOP BOLT

JAM NUT

ANTI TORQUE

IDLER BELLCRANK

LEFT STOP BOLT

JAM NUT

FLOOR MOUNTED

CONTROL ROD

PEDAL ARM ALIGNMENT AND

STOP BOLT ADJUSTMENT

G67−2011

Figure 502. Pilot Pedal Rigging

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MD Helicopters, Inc.

CSP-HMI-2

MAINTENANCE MANUAL

(11).

Apply full left pedal until the rigging

5. Thruster Control Rigging (500N)

pin can be inserted through the bracket

(Ref. Figure 503)

assembly upper hole and into the slot

marked ``L'' in the gear pinion rack Sta.

113.00 splitter assembly (View D).

Consumable Materials

(Ref. Section 91−00−00)

(12).

Adjust the left-hand stop-bolt in the

Item

Nomenclature

pilot's pedal support so that the stop

CM702

Lockwire CRES

just comes in contact with the link

assembly (View A).

Special Tools

(13).

Remove the rigging pin assembly and

(Ref. Section 91−00−00)

adjust right-hand stop-bolt in the

Item

Nomenclature

pilot's pedal support.

ST601

Rigging pin

(14).

Apply full right pedal until the rigging

pin assembly can be inserted through

NOTE:

the bracket assembly upper hole and

D Thruster control rigging to be accom

into the slot marked ``R'' in the gear

plished with the splitter spring installed,

pinion rack Sta. 113.00 splitter assem

the fan pitch control rigging completed,

bly (View D).

the tailboom sector control rod assembly

and stationary thruster cone installed.

(15).

Adjust the right-hand stop-bolt in the

pilot's pedal support so that the stop

D Do not adjust the control rodend beyond

just comes in contact with the link

the witness hole, do not tighten jamnuts

assembly (View A).

until after final adjustment.

NOTE: For dual installation, adjust the stop-

(1). Insert rigging pin (ST601) into the

bolts in the co-pilot's support bracket to

bracket assembly lower rigging hole

match the pilot's pedal travel. Repeat steps

and through the slot on the pinion gear

(11). thru (13).

rack Sta. 113.00 splitter assembly (View

D).

4. Anti−Torque Pedal Friction Installation

(2). Removed pan cover.

and Adjustment

(3). Adjust rodend until it can be attached

(Ref. Figure 403)

to input clevis of sector assembly (View

C).

(1). Using two pieces of wood and C-clamp

or rope, secure pilot's pedals in mid

(4). Connect sector clevis control rod.

position so they are aligned within 0.50

inch (1.27 cm) of each other.

(5). Install bushing, washer and bolt.

Torque bolt 30 - 40 inch-pounds (3.39

(2). Install washer, bolt, bushing, and link

- 4.52 Nm). Safety wire (CM702) bolt

assembly to bracket assembly on

(Ref. Anti-Torque Flight Control

instrument console.

Installation).

(3). Install brace and clamp arm assembly

(6). Remove rigging pin from splitter

to anti-torque tube assembly.

assembly.

(4). Install friction disc, link, retainer and

NOTE: Removed safety clips from turnbuckles

spring, install washer (shim washers if

are not to be reused.

required) and nut.

(7). Remove safety clips and adjust the two

(5). Torque brace and arm assembly bolts

turnbuckles until a second rigging pin

30 - 35 inch-pounds (3.39 - 3.95

(ST601) can be inserted through a slot

Nm). Torque nut against washer to

in the output drum assembly and

obtain a pedal friction of 5 - 8 pounds

through holes in drum output support

(2.27 - 3.63 kg).

(View A and B).

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MD Helicopters, Inc.

CSP-HMI-2

MAINTENANCE MANUAL

RIGGING PIN

INPUT SECTOR

PAN COVER

ROD ASSEMBLY

PAN

RACK GEAR

ROTATING

STATIONARY

THRUSTER CONE

SLOT

0.00 +0.25 IN.

(0.00 +6.4 MM)

RIGGING PIN

VIEW LOOKING FORWARD

PINION GEAR

600N THRUSTER OPENING

G67-2014-2C

Figure 503. Thruster Control Rigging (Sheet 2 of 2)

(8). Using a cable tensiometer, adjust cable

(12). Safety wire (CM702) bolts.

tension to 20 - 40 pounds (9.07 -

(13). Thruster Control Rigging shall produce

18.14 kg).

the following results:

NOTE: Removed safety clips from turnbuckles

(a). Full left pedal; rotating thruster cone

are not to be reused.

to be fully open to the left side of the

(9). Install safety clips in turnbuckles.

tailboom.

(b). Full right pedal; rotating thruster

(10). Remove rigging pins.

cone to be open a minimum of 11.80

(11). Install rotating thruster cone using

inches (29.97 cm) when measured

three bolts and washers. Torque bolts

from the lower edge of the right

70 - 90 inch-pounds (7.91 - 10.17

opening to the upper lip of the

Nm).

rotating cone.

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MD Helicopters, Inc.

MAINTENANCE MANUAL

6. Thruster Control Rigging (600N)

(8). Using a cable tensiometer, adjust cable

tension to 20 - 40 pounds (9.07 -

18.14 Kg) by adjusting the two turn

(Ref. Figure 503)

buckles.

Consumable Materials

(9). Remove rigging pins.

(Ref. Section 91−00−00)

(10). Install rotating thruster cone using

Item

Nomenclature

three bolts and washers.

CM701

Lockwire CRES

(11). Push full left pedal and verify bottom

Special Tools

edge of rotating thruster opening is

(Ref. Section 91−00−00)

within 0.00 ±0.25 inch (0.0 ±6.4 mm) of

Item

Nomenclature

edge of stationary thruster cone (Ref.

Figure 503); adjust turnbuckles as

ST601

Rigging pin

necessary.

NOTE: Do not adjust the control rodend beyond

(12). Remove rotating thruster cone.

the witness hole, do not tighten jamnuts un

(13). Verify cable tension.

til after final adjustment.

(14). Reinstall rotating thruster cone; Torque

(1).

Insert rigging pin (ST601) into bracket

rotating thruster cone bolts to 70 - 90

assembly lower rigging hole and

inch-pounds (7.91 - 10.17 Nm).

through slot on the pinion gear Sta.

113.00 splitter assembly (Ref.

NOTE: On the 600N helicopter, the pedal po

Figure 503).

tentiometer rigging must be checked any

time the anti-torque system has been ad

justed.

(2).

Removed pan cover.

(15). Safety bolts with lockwire (CM701).

(3).

Adjust rodend until it can be attached

to input clevis of sector assembly and

(16). Safety turnbuckles with clips.

the rigging slot in input sector assem

bly aligns with the rigging hole in pan.

7. Left Vertical Stabilizer Assembly Rigging

(500N, and 600N with YSAS)

(4).

Connect sector clevis control rod.

(Ref. Figure 504)

(5).

Install bushing, washer and bolt.

Special Tools

Torque bolt 70 - 90 inch-pounds (7.91

(Ref. Section 91−00−00)

- 10.17 Nm). Safety bolt with lockwire

Item

Nomenclature

(CM701) (Ref. Anti-Torque Flight

ST601

Rigging pin

Control Installation).

NOTE:

(6).

Reinstall pan cover ensuring rigging

pin hole in pan cover aligns with

D Rigging to be accomplished with the tail

rigging hole in sector assembly. If pin

boom and vertical stabilizers, splitter as

cannot be inserted through fan cover,

sembly bungee spring and engine air inlet

sector assembly and pan, repeat above

fairings installed.

steps.

D Do not adjust the control rodend beyond

the witness hole, do not tighten jamnuts

(7).

Adjust the two turnbuckles until a

until after final adjustment.

second rigging pin can be inserted

through a slot in the output drum

(1).

500N helicopters: Insert rigging pin

assembly and through holes in drum

(ST601) into the bracket assembly

output support.

upper hole and into the slot marked

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CSP-HMI-2

MAINTENANCE MANUAL

``R'' in the gear pinion rack Sta. 113.00

NOTE: The actuator and control tube can be

splitter assembly (View A) splitter

slid out the horizontal stabilizer end panel

assembly upper hole.

far enough to remove safety wire and loosen

the jamnuts. The control tube can be rotated

(a). Adjust the left vertical stabilizer to

and adjusted similar to a turnbuckle.

6.5 ±0.5 degrees on the horizontal

(6).

500N helicopters: Using the top rig

stabilizer degree plate (View C).

plate, adjust right vertical stabilizer to

4.0 ±0.5 degrees.

(b). Remove rigging pin.

(7).

600N helicopters: Using the top rig

(2).

600N helicopters: With pedals set to full

plate, adjust top right vertical stabilizer

right position, adjust tip of the left

to -1.75 ±0.25 degrees.

vertical stabilizer trailing edge to 12

degrees.

(8). After adjustment, slide actuator and

control tube out far enough to tighten

(3). Check witness holes for proper thread

and safety jamnuts.

engagement. Rodends are to be

(9). Reinstall actuator and control tube.

installed equal distance on torque tube

to within 0.020 inch (0.508 mm) of each

NOTE: On the 600N helicopter, the pedal po

other.

tentiometer rigging must be checked any

time the anti-torque system has been ad

Stability Augmentation System Rigging

justed.

Instructions (500N, and 600N with YSAS)

9. Vertical Stabilizer Assembly Rigging

(Ref. Figure 505)

(600N without YSAS System)

(Ref. Figure 506)

Special Tools

(Ref. Section 91−00−00)

Special Tools

Item

Nomenclature

(Ref. Section 91−00−00)

ST1013

Yaw S.A.S. test box

Item

Nomenclature

ST601

Rigging pin

(1).

Turn OFF power supply, turn S.A.S.

switch on the instrument panel to the

NOTE:

OFF position.

D Rigging to be accomplished with the tail

boom and vertical stabilizers installed.

(2).

Install the Yaw S.A.S (ST1013). Test

Box to the computer located and

D Do not adjust the control rodend beyond

mounted on the co-pilot's seat structure

the witness hole, do not tighten jamnuts

forward bulkhead, the test box is now

until after final adjustment.

in series with the computer and

(1). Insert rigging pin (ST601) into the

actuator.

bracket assembly upper hole and into

the slot marked ``R'' in the gear pinion

(3).

Using the aircraft power supply or an

rack Sta. 113.00 splitter assembly.

external power source, activate S.A.S.

switch.

(2). Push trailing edge of left vertical

stabilizer to the right using only enough

(4).

Adjust actuator to the fully extended

force to eliminate freeplay (5-lb (0.3

position using the Yaw S.A.S. test box.

Kg) max).

(5).

Turn aircraft power OFF, actuator

(3). Adjust control rod for the left vertical

should remain in fully extended

stabilizer to 10.5 ±0.5 degrees on the

position.

horizontal stabilizer degree plate.

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MD Helicopters, Inc.

MAINTENANCE MANUAL

(4). Push trailing edge of right vertical

(c). File smooth all surfaces of spacer and

stabilizer to the right using only enough

plates.

force to eliminate freeplay, 5 lbs (0.3

(d). Chamfer one 9.00 inch (22.86 cm)

Kg) maximum.

edge of each plate, 0.060 x 0.100 inch

(5). Adjust control rod for the right vertical

(1.524 x 2.54 mm) (this will be the

stabilizer to 14.5 ±0.5 degrees on the

front of the tool) as indicated in

horizontal stabilizer degree plate.

Figure 507.

(6). Remove rigging pin.

(e). Stack plates, chamfered edges facing

each other with spacer between

NOTE: On the 600N helicopter, the pedal po

plates and flush with aft side of

tentiometer rigging must be checked any

plates (un-chamfered edge).

time the anti-torque system has been ad

justed.

(f). Drill and rivet angle tool together,

size and type of rivets optional.

10. Vertical Stabilizer Trim Tab Adjustment

B. Trim Tab Adjustment

and Tool Manufacturing (600N without

YSAS)

(Ref. Figure 506) Adjust vertical stabilizer trim

tabs to improve directional handling character

A. Trim Tab Tool Manufacturing

istics and to minimize pedal forces in forward

flight.

(Ref. Figure 507)

For best results, aircraft should be weighted

(1). Manufacture guide as follows:

down to normal operating weight during test

flights while doing tab adjustments.

(a). Cut guide from 0.130 inch (3.30 mm)

2024-T3 aluminum sheet 7.00 inch

NOTE:

(17.78 cm) x 4.50 inch (11.43 cm).

D Ensure vertical stabilizers are rigged cor

(b). Measuring 1.73 inch (4.39 cm) from

rectly (Ref. Vertical Stabilizer Assembly

bottom, make V-cut in guide 1.030

Rigging (600N)).

inch (2.62 cm) wide and 3.79 inch

D Ensure there is no play between the

(9.63 cm) deep.

500N7213-5 bellcrank assembly and the

500N7212-3 shaft.

(c). File 0.070 inch (1.78 mm) wide x

0.260 inch (6.60 mm) deep slot in aft

D Ensure there is minimal play between the

end of V-cut.

upper and lower vertical stabilizers.

D When installing new upper vertical stabi

(d). File smooth all surfaces of guide.

lizers, if previous tab settings were not re

corded, left trim tab should be set to zero

NOTE: Note the difference in the degree mark

degrees and right trim tab should be set

ings between the top and bottom of the

to 10° right (viewed looking forward from

guide.

the rear).

(e). Etch degree marks in guide as

D The right vertical stabilizer tends to af

indicated in Figure 507.

fect pedal pressure more than the left.

The left vertical stabilizer tends to affect

(2). Manufacture angle tool as follows:

flight characteristics more than the right.

(a). Cut two plates from 0.130 inch (3.30

Left Vertical Tab

Right Vertical Tab

mm) 2024-T3 aluminum sheet 9.00

inch (22.86 cm) x 2.00 inch (5.08 cm).

0°

10° Right

(b). Cut a spacer from 0.040 inch (1.016

(1). Determine which pedal requires excess

mm) 2024-T3 aluminum sheet 9.00

pressure to attain proper trim during

inch (22.86 cm) x 1.00 inch (2.54 cm).

straight flight.

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CSP-HMI-2

MAINTENANCE MANUAL

20°

0.050 IN.

10°

(12.70 MM)

0°

10°

RIVETS

20°

(4 PLCS)

THIS SIDE UP

9.00 IN.

(22.86 CM)

4.05 IN.

(10.29 CM)

3.79 IN.

(9.63 CM)

4.50 IN

(11.43 CM)

20°

10°

1.03 IN. (2.62 CM)

0°

10°

0.07 IN.

(1.78 MM)

20°

1.73 IN.

(4.40 CM)

R0.060-0.100 IN.

THIS SIDE DOWN

(1.524-2.54 MM)

0.130 IN.

(3.302 MM)

MAX

7.00 IN.

0.040 IN.

(17.78 CM)

(1.016 MM)

2.00 IN.

1.00 IN.

(5.08 CM)

(2.54 CM)

GUIDE

6G67-092-2

Figure 507. Vertical Stabilizer Trim Tab Bending Tool

NOTE:

Do not bend tabs beyond 20° in

CAUTION

either positive or negative direc

D Always adjust right vertical stabilizer

tion. Tabs and/or vertical stabilizer skin can

trim tab first. If tab is bent to a maximum

be damaged.

of 20° before correct pedal pressure can be

NOTE:

achieved, go to left tab and continue ad

justments.

D Bending tabs to the right will decrease

left pedal pressure.

D Limit tab adjustments to 5° increments

D Tab angles are acceptable when left pedal

between flights.

forces are between 2 and 5 lbs. (0.91 and

2.27 Kg) in stabilized flight and the flight

D Exceeding 20° tab adjustments may cause

characteristics are acceptable.

a ”tail wag” condition.

(4). Bend tab in direction needed to relieve

pedal pressure and improve flight

(2). Position guide on right vertical stabiliz

characteristics.

er over trim tab.

(5). Remove tab tools and fly aircraft, see

chart below, to determine if pedal

(3). Position angle tool on trim tab.

pressure was relieved.

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MD Helicopters, Inc.

MAINTENANCE MANUAL

(6). Repeat above steps until pedal pressure

Pedal Position

Pedal Force

and handling characteristic are cor

rected.

Hover

*60 KIAS

NOTE: After trim tab adjustments, position

guide on both the top and bottom of trim tab

*80 KIAS

to ensure tab is straight.

*100 KIAS

(7). Log trim tab setting in log book.

*120 KIAS

*130 KIAS

NOTE: *Level flight

Handling: Low pedal forces might require bending

tabs in opposite directions.

Table 501. Flight Controls Troubleshooting

Pedal Kick−Thru or Binding

Noticeable hump in pedals (kick−thru) in flight.

yes ⇓

Are control cables Binding?

no Is there binding in control rod at

no Is there pedal binding in flight?

⇒ fan transmission?

⇒

yes ⇓

Replace worn or binding

Adjust control rod for proper

Check for dry roller bearings at

control cable(s).

clearance.

rotating cone.

Dutch Roll

Is there relative movement

no Is there play when holding cone

no Bend left tab to the left, starting

between upper and lower

⇒ and moving the vertical

⇒ with 5° left.

verticals?

stabilizers?

yes ⇓

Check for loose attaching

Check for loose bellcrank at

hardware for the upper and

control shaft.

lower verticals (NOTE).

NOTE: When tightening hardware, do not torque fasteners beyond specified torque limits.

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MAINTENANCE MANUAL

NOTAR® ANTI−TORQUE SYSTEM FLIGHT CONTROLS

INSPECTION/CHECK

1. Upper Fuselage and Tailboom Control

(4). Inspect control rod fitting, torque tube

Linkage Inspection

mounting bracket and pedal mounting

bracket for cracks and corrosion. Using

(Ref. Figure 401)

an 8X magnifying glass, mirror and

flashlight, closely inspect pedal link

(1). Inspect rod end bearings for binding

bellcrank fitting of pedal bracket in

and excessive wear (0.040 inch (1.016

center forward area where fitting (fork

mm) maximum axial play). Inspect

piece) joins tubular section. If any

rivet at fixed rod end.

cracks are detected, replace bracket

assembly. Inspect bracket bearings for

(2). Inspect control rod for surface damage

excessive looseness.

and evidence of bending.

(5). Inspect torque tube for cracks,

(3). Inspect rubber boot just forward of Sta.

scratches, nicks, dents and similar

137.50 bulkhead for condition.

surface defects.

(4). Inspect control rod surfaces serviceabil

(6). Inspect pedal brackets for corrosion.

ity, wear is limited to thickness of hard

3. Sta. 97.50 (500N) or Sta. 95 (600N)

anodic coating.

Bellcrank and Support Bracket Inspection

(5). Inspect bellcranks for scratches, cracks,

(1). Inspect bellcrank and support bracket

corrosion and similar surface defects.

for cracks, corrosion and other similar

Check that all bushings are secure.

surface defects.

(6). Inspect bellcrank bearings for looseness

(2). Check that all bushings are secure.

and binding.

Check bellcrank bearings for looseness

and binding.

(7). Visually inspect bellcrank supports for

cracking/damage.

(3). Inspect rod ends bearings for binding

and excessive wear (0.040 inch (1.016

mm) maximum axial play). Inspect

Anti−Torque Pedal Assembly Inspection

control rod surface serviceability, wear

(Ref. Figure 502)

is limited to thickness of hard anodic

coating. Inspect for safety wire at

NOTE: Inspect components at left and right po

rodends and lockwasher as required.

sition on the right-hand command models.

Bolts for cotter pins as required.

Check that corresponding pedals contact

4. Forward and Intermediate Directional

stops simultaneously.

Control Tube, and Link Inspection

(1). Inspect pedals and pedal arms for

(1). Inspect rodend and link bearings for

cracks, elongated pedal attach holes

binding and excessive wear (0.040 inch

and open drain holes. Inspect teflon-

(1.016 mm) maximum axial play).

reinforced bushing liners for deteriora

tion.

(2). Inspect control tubes and link for

surface damage and wear. Inspect

(2). Inspect pedal-to-arm quick-release

control tubes surface serviceability,

locking pin for condition and positive

wear is limited to thickness of hard

spring action.

anodic coating.

(3). Inspect links and bellcrank for cracks

(3). Inspect for safety wire at rodends and

and bends, and bearings for excessive

lockwasher as required. Bolts for cotter

play.

pins as required.

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MD Helicopters, Inc.

MAINTENANCE MANUAL

Splitter Bungee Spring Inspection (500N)

and female connectors for corrosion

pitting or cracks; none allowed.

(1). Inspect spring support bracket for loose

(8). Inspect center cable hex end for wear

rivets, loose screws, corrosion and

beyond allowable tolerance (Ref.

cracks and general condition.

Figure 601).

(2). Check link assemblies for cracks, bends

(9). Inspect collar for wear in locking

and dents.

groove.

(3). Inspect spring for condition and a

(10). Inspect relieved area, at Sta. 123.30,

positive spring action.

between threads and swage for crack or

evidence of corrosion.

Sta. 113.00 Splitter Assembly and

(11). Inspect relieved area, at Sta. 164.00

Bellcrank Inspection

(500N) or Sta. 292.00 (600N), between

(1). Visually inspect bellcrank and support

threads and swage for crack or evidence

bracket for cracks and damage using 5X

of corrosion.

power magnifying glass.

(12). Inspect forward cable coupling opening

for proper dimension (Ref. Figure 601).

(2). Inspect for cracks, corrosion and other

similar surface defects.

(13). Using a bright light and 10x magnify

ing glass, inspect the swaged area of

(3). Check that all bushings and bearings

the telescopic swivel end for cracks

are secure.

(Ref. Figure 603).

(4). Inspect rodend bearings for binding and

(14). Inspect for any evidence of swivel ball

excessive wear (0.040 inch (1.016 mm)

separation.

maximum axial play). Inspect control

8. YSAS Actuator, Rate Gyro and Electronic

rod surface serviceability, wear is

Control Box Inspection

limited to thickness of hard anodic

coating. Inspect for safety wire at

(1). Inspect YSAS actuator for damage, no

rodends and lockwasher as required.

damage allowed.

Bolts for cotter pins as required.

(2). Inspect mounting hardware for proper

installation and general condition.

Forward and Center Cable Assembly

Inspection

(3). Inspect wiring for condition, no fraying,

cracking of insulation or chafing

(1). Inspect for freedom of movement and

allowed.

no binding.

(4). Inspect grommet for proper installation

(2). Check rodend bearings for corrosion,

and deterioration, replace if deterio

and wear.

rated.

(3). Cable housing for fraying, and security.

(5). Inspect mounting bracket for cracks

(pay particular attention to area around

(4). Inspect cable couplings for wear,

four rivet attach holes) no cracks

deformation or damage (Ref.

allowed.

Figure 602).

(6). Inspect rate gyro and electronic control

(5). Inspect inner cable coupling hex for

box for damage, security in mount and

proper alignment with outer cable

ensure electrical plugs are secure.

coupling.

(7). Inspect mounting bracket for cracks, no

cracks allowed.

(6). Inspect cable inner couplings for

deformation or obvious damage.

9. Fan Pitch Control Tube Inspection

(7). Using a bright light and 10X magnify

(1). Inspect tube for dents, scratches, nicks,

ing glass, inspect inner coupling male

gouges and corrosion, none allowed.

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CSP-HMI-2

MAINTENANCE MANUAL

(2). Inspect for visible step in splined area.

(b). Minimum measurement across pins

is 0.640 in. (16.256 mm).

(3). If step is evident:

(a). Measure across splines using 0.096

in. (2.4384 mm) diameter pins.

Table 601. Isolating Control System Troubles

Symptom

Isolating Step

Corrective Action

Binding, locking−up and erratic

Disconnect fwd control tube from

If symptom is gone, check from

action of foot pedals (Do not force

Sta. 113.00 splitter assembly.

splitter assembly aft.

controls).

0.250 INCH (6.35 MM)

HEX (REF)

CLOSED

OPEN

POSITION

(REF TABLE)

HEX CONFIGURATION

FORWARD CABLE FEMALE END

ROUND CONFIGURATION

ACCEPTABLE DIMENSIONS

CENTER CABLE (-5) (INSIDE TAIL BOOM)

SLOT DIMENSION

MALE CONNECTOR

(MM)

0.450

(11.43)

HEX CONFIGURATION

0.260 IN. (6.604 MM) MIN.

(NOTE)

0.685

(17.40)

ROUND CONFIGURATION

0.450

(11.43)

ROUND CONFIGURATION

0.250 IN.

UNACCEPTABLE DIMENSIONS

(6.35 MM)

0.685

(17.40)

HEX CONFIGURATION

DIMENSION ACROSS HEX

(ROTATED)

NOTE: WHEN DIMENSION REACHES 0.260 IN. (6.604 MM) ACROSS ANY

TWO OPPOSING POINTS OF HEX, CABLE HAS REACHED IT'S MAXIMUM

G67-2020B

WEAR AND MUST BE REPLACED WITH A SERVICEABLE CABLE.

Figure 601. Control Cable Coupling Inspection

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MD Helicopters, Inc.

MAINTENANCE MANUAL

10. Sector Assembly, Control Cables and

(a). Fraying or corrosion; no fraying or

Drum Assembly Inspection

corrosion allowed.

(Ref. Figure 402)

(b). Proper installation of turnbuckle

safety clips.

(1). Inspect sector assembly for:

(c). Corrosion or cracking on turnbuckles;

(a). Proper installation of mounting

no corrosion or cracking allowed.

hardware.

(d). Proper cable tension.

(b). Remove access cover from pan

assembly.

(6). Reinstall access cover on top of station

ary thruster assembly (600N).

(c). Center cable mounting bolt for

security and proper installation of

(7). Inspect control cable pulleys for:

safety wire.

(a). Proper installation of mounting

In the following step, ensure

hardware.

WARNING

the anti-torque pedals are

not moved, personal injury can occur.

(b). Guard pins installed.

(d). Check sector assembly for excess

(c). Excessive groove in pulleys; evident

up-and-down play.

in out-of-round pulley.

(e). Damage, cracks or corrosion; no

(8). Inspect drum assembly for:

damage, cracks or corrosion allowed.

(a). Proper installation of mounting

(f). Reinstall access cover on pan assem

hardware.

bly.

(b). Damage, cracks or corrosion; no

(2). Remove tip cap (500N).

damage, cracks or corrosion allowed.

(3). Remove rotating cone assembly.

(c). Guard pins installed.

(4). Remove access cover from top of

stationary thruster assembly (600N).

(9). Reinstall rotating cone assembly.

(5). Inspect control cables for:

(10). Reinstall tip cap (500N).

Page 606

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CSP-HMI-2

MAINTENANCE MANUAL

NOTAR® ANTI−TORQUE SYSTEM FLIGHT CONTROLS

REPAIRS

1. Anti−Torque Flight Control Repair −

have equal space for angular throw;

General

tighten jamnut.

Use care when drilling to re

(6). If removed, install rivet to secure

CAUTION

move or install riveted rod end;

rodend.

rod end is steel and rod and bearing adapter

(7). Ensure slotted bushing is in place.

are aluminum.

(8). Secure control rod in torque tube fitting

2. Sta. 97.50 (500N) or Sta. 95 (600N)

or idler bellcrank with bolt, two

Bellcrank and Support Bracket Repair

washers, nut and cotter pin.

4. Upper Fuselage Sta. 113.00 Splitter

Consumable Materials

Assembly Repair

(Ref. Section 91-00-00)

Item

Nomenclature

Refer to Field Service Department for repairs.

CM321

Surface primer locking compound

5. Intermediate Control Tube Repair

CM431

Sealing, locking and retaining compound

(1). Perform straightness check on inter

mediate control rod that appears bent

(1). Replace unserviceable bearings.

or bowed. Total length of control rod

(2). Install new bearings with surface

(excluding rod ends) must be straight

primer (CM321) and grade A locking

within 0.040 inch (1.016 mm), with

compound (CM431).

straightness variation limited to

maximum of 0.010 inch (0.254 mm) in

NOTE: When idler bellcrank bearing are re

each foot of length.

placed, ensure idler bellcrank spacers are

NOTE:

reinstalled between bearings.

D A dye check for cracking must always be

(3). Replace bellcranks or control support

performed after cold-straightening. Re

brackets that have cracks or enlongated

place cracked rod, or cracked or bent rod

holes.

end.

D Do not use rod ends to support rod during

Forward Directional Control Tube Repair

straightening process.

(1). Replace control rod end if bearing axial

(2). Cold-straighten bent rod that is not

play is more than 0.040 inch (1.016

within tolerance provided there are no

mm). Set initial control rod length and

nicks or sharp dents in bend length.

bearing angularity.

(3). Replace control rod end if bearing axial

(2). Initial length forward directional

play is more than 0.040 inch (1.016

control tube is 15.42 inches (39.17 cm).

mm). Set initial control rod length and

Rod end angularity is 0 degrees

bearing angularity.

straight line within ±2 degrees.

(4). Replace unserviceable control rod

(3). Perform straightness check on control

bearing adapter if installed.

rods that appear bent or bowed.

(a). Measure length and record position

(4). Drill out rivet. Loosen jamnut and

of rod end in adapter.

unscrew rodend.

(b). Remove affected rod end. Initial

(5). Screw replacement rodend into rod to

installation length of intermediate

obtain same measurement made in step

control rod is 23.68 inches (60.15 cm).

b. Align control rodends so bearings

Rod end angularity is 40 ±2 degrees.

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MD Helicopters, Inc.

MAINTENANCE MANUAL

(c). Drill out rivets securing adapter to

(8). Repair minor surface defects such as

rod and aft rod end.

scratches, nicks and corrosion on

bellcranks and support bracket.

(d). Install rod end in replacement

(9). Use abrasive cloth (CM802), grade 400

adapter and position at recorded

- 600, to smooth out and blend in such

measurement.

defects.

6. Sta. 137.50 Support Bracket and Bellcrank

(10). Cast surfaces may be reworked to depth

Repair

of 0.020 inch (0.508 mm).

(11). Repair surface abrasion on control rod

by smoothing area with grade 400

Consumable Materials

(Ref. Section 91-00-00)

abrasive cloth (CM802) and restoring

Item

Nomenclature

protective finish with primer (CM318).

CM318

Primer

(12). Replace rod if wear or depth of repair

CM321

Surface primer locking compound

exceeds 0.004 inch (0.102 mm).

CM431

Sealing, locking and retaining compound

CM802

Abrasive cloth, aluminum oxide

(13). Replace tailboom control rod if hard

anodic coating is worn through and

aluminum base metal is visible.

(1).

Replace unserviceable bearings.

(14). Replace split or torn boot.

(2).

Install new bearings with surface

primer (CM321) and grade A locking

7. Fan Pitch Control Tube Repair

compound (CM431).

Refer to Field Service Department for repairs.

(3).

Flat machined surfaces, except clevis

8. Forward Cable Assembly Repair

inner ears, may be reworked to depth of

0.015 inch (0.381 mm).

Refer to Field Service Department for repairs.

(4).

Clevis inner ear surfaces may be

9. Center Cable Assembly Repair

reworked to depth of 0.020 inch (0.508

Refer to Field Service Department for repairs.

mm).

10. Aft Control Rod Repair

(5).

Machined holes may have 0.003 inch

(0.076 mm) removed from bore wall in

Refer to Field Service Department for repairs.

an area no greater than 15 percent of

circumference and 50 percent of depth.

11. Thruster Sector Assembly Repair

Refer to Field Service Department for repairs.

(6).

All edges may have 0.030 inch (0.762

mm) removed except around machined

12. Drum Assembly and Idler Pulleys Repair

holes, which are limited to 0.010 inch

(0.254 mm) chamfer.

Refer to Field Service Department for repairs.

(7).

All rework must be smoothly blended

13. Anti−Torque Pedal Disassembly

into adjacent surfaces and finish must

(Ref. Figure 403)

be restored.

NOTE: Before disassembly of pedal installa

NOTE: Installation direction of Sta. 137.50

tion, matchmark mating pedal arms, links

bellcrank bearing may be from either side,

and bellcranks with pedal brackets to avoid

depending on location of bearing shoulder.

intermixing components between locations

There must not be less than 0.010 inch

at reassembly.

(0.254 mm) protrusion of bearing inner race

beyond sides of bellcrank after bearing is in

(1). Disconnect links from pedal arms and

stalled.

bellcrank; remove links.

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MAINTENANCE MANUAL

(2). Remove bellcrank from pedal bracket.

Right pedal arm bushings are

CAUTION

glass-filled phenolic. Do not

(3). Remove nut and washer of two bushing

cock bushings during replacement; ensure

assemblies that secure left pedal arm

bushing is fully seated in arm bore. Keep

and control rod fitting to torque tube.

tools from contact with bushing liners to

avoid fraying.

(4). Carefully remove bushing bolt and

temporarily reinstall washer and nut

(6). Replace bearings in right pedal arm

on bolt.

when teflon-reinforced liner is galled or

frayed. Pull bushing to remove; press to

(5). Slide pedal bracket and pedal arms off

install.

end of torque tube.

(7). Remove corrosion from pedal brackets

NOTE:

(Ref. Sec. 20-40-00 and CSP-A-3,

D Do not remove two teflon-lined bushings

Corrosion Control Manual).

from right pedal arm unless replacement

15. Anti−Torque Pedal Reassembly

is required.

D Do not remove two stop bolts, jam nuts on

(Ref. Figure 403)

stop bolts or bearings from pedal bracket

(1).

When reassembling components, check

unless replacement is required.

for correct matchmark identification.

(6). Slide torque tube bracket and control

(2).

If previously removed, thread jamnut

rod fitting off torque tube.

on each of two stop bolts and install two

stop bolts into threaded inserts of pedal

14. Anti−Torque Pedal Repair

brackets.

(3).

Slide torque tube bracket and control

Consumable Materials

rod fitting onto torque tube.

(Ref. Section 91-00-00)

Item

Nomenclature

(4).

Locate pedal bracket and pedal arms

CM425

Sealing compound

for correct position on torque tube; slide

CM431

Sealing, locking and retaining compound

bracket and arms onto torque tube.

(5).

Fasten left pedal arm and control rod

(1). Replace parts that are cracked or have

fitting to torque tube with adjustable

elongated attachment holes.

bushing assemblies.

Do not attempt to straighten

(6).

Install bushing bolt so shank at

CAUTION

bent torque tube or pedal link.

bolt-head end protrudes at least 0.002

inch (0.051 mm).

(2). Replace unserviceable pedal covers.

Apply sealing compound (CM425) to

(7).

Torque nut to 50 - 80 inch-pounds

approximately 30 percent of upper and

(5.65 - 9.04 Nm) plus drag torque; do

lower edge surfaces that contact pedal.

not allow bolt to turn.

Cure according to container instruc

tions.

(8).

Ensure each end of bushing assembly

shank protrudes a minimum of 0.002

(3). Replace complete pedal link if cracked

inch (0.051 mm). If not, loosen and

or contains unserviceable bearings;

repeat above steps.

bearings are not replaceable.

(9).

Ensure slotted bushing is in place; then

(4). Replace unserviceable bearings in

attach bellcrank to pedal bracket with

mounting brackets or pedal link

bolt, two washers, nut and cotter pin.

bellcrank.

(10).

Ensure slotted bushings are in place;

(5). Install replacement with grade A

then fasten each link to bellcrank with

locking compound (CM431).

bolt, two washers, nut and cotter pin.

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MD Helicopters, Inc.

MAINTENANCE MANUAL

(11). Ensure slotted bushings are in place;

(f). Remeasure and record dimension

then fasten each link in pedal arm lugs

``C''.

with bolt, two washers, nut and cotter

pin.

(6). Cut lockwire and remove the four

screws that hold the seal housing and

(12). Ensure outboard pedals clear windows

splined housing.

by a minimum of 0.20 inch (5.08 mm)

with 20 pounds (9.07 kg) of force

NOTE: It may be necessary to grasp the cylin

applied.

drical portion of the seal housing or splined

housing with a rubber-tipped clamping tool

16. YSAS Actuator Regrease Procedure

to loosen the housing because of primer ap

plied to the screws at assembly.

A. YSAS Actuator Disassembly

(7). If there is an inspection seal at the

(Ref. Figure 801)

housing joint, remove enough of the

Do not attempt to loosen or

label so that it cannot get pinched

CAUTION

between the housings when the actua

tighten nut by grasping actua

tor housing, damage to spline housing can

tor is re-assembled. Leave some of the

occur.

label on the actuator to aid in re-as

sembly. If there is no inspection seal,

(1). Cut and remove lockwire from lock

use pieces of tape.

washer and nut.

NOTE: Belleville spring, spacer and shims (if

(2). Hold hex end of output shaft and loosen

installed) are installed between the seal

nut.

housing and splined housing.

(3). Remove rod end, nut and lockwasher.

(8). Remove seal housing and splined

housing.

(4). Record output shaft orientation by

marking the notch on the connector

(9). Note the order of assembly of these

side of the shaft with a pencil.

parts.

(5). Measure endplay of the actuator as

follows:

(10). Measure and record the thickness of the

spacer and the total thickness of the

(a). Push the output shaft in towards the

shims (if installed) to avoid confusion

actuator housing by applying a load

with the spacer and shims on the other

of 20 -100 lbs (9.07 - 45.36 kg).

side of the splined housing.

(b). Using a depth gage, measure and

NOTE: The teflon washer attached to the end of

record dimension ``C''.

the LVDT core is a close fit to the bore

through the LVDT housing, it may be neces

(c). Screw the rod end into the output

sary to carefully tug a little to fully remove

shaft a few turns.

the shaft.

(d). Pull on the output shaft by applying

(11). Unscrew and remove the output shaft.

a load of 20 -100 lbs (9.07 - 45.36

This shaft has the LVDT core and

kg).

associated hardware attached to it; Do

not unscrew the nylon screw or the

(e). Unscrew and remove the rod end

LVDT core.

without changing dimension ``C''.

NOTE: If the variation in dimension ``C'' ex

(12). Note the orientation of the belleville

ceeds 0.013 inch (0.3302 mm), the actuator

spring, spacer and shims (if installed).

should be returned to the manufacturer for

Measure and record the thickness of the

repair rather than regrease.

spacer and shims.

Page 804

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CSP-HMI-2

MAINTENANCE MANUAL

Do not use any cleaning sol

NOTE: If you mix grease, only use Mobil

CAUTION

vents. Damage to the motor

Grease 28 which meets MIL-G-81322.

bearings and the molybdenum disulfide fin

(4). If necessary, mix 95% aircraft grease

ish on the acme nut and spline surfaces may

(CM111) with 5% molybdenum disulfide

occur.

powder (CM109) by weight.

(13). Wipe off old grease from all parts using

(5). Apply special grease (CM127) to acme

lint-free cloth.

screw threads until scale is balanced

(14). Using cotton swabs, remove grease

again.

from acme nut area. Be sure to reach

(6). Evenly distribute grease around the

into the cavity just beyond the acme

acme screw threads to form a fairly

nut threads to remove grease deposits.

even cylinder in order to fit through the

(15). Use the acme screw to remove grease

belleville spring without scraping off

from the acme nut threads.

too much grease.

(a). Run screw in and out, then wipe

(7). With belleville spring, spacer and shims

threads clean.

(if installed) in place within end bore in

motor housing, carefully assemble

(b). Repeat above step until no more

greased output shaft to actuator.

grease appears on screw threads.

(a). Screw in the shaft until the leading

B. YSAS Actuator Regrease and

edge of the spline on the shaft is

Reassembly

about flush with the end of the motor

housing and oriented so that the

(Ref. Figure 801)

splined housing can be put on in it's

proper orientation.

Consumable Materials

(8). Apply grease (CM127) to splined

(Ref. Section 91-00-00)

surfaces of splined housing until

Item

Nomenclature

grooves are completely full. Install

CM109

Molybdenum disulfide powder lubricant

splined housing as originally oriented.

CM111

Grease, aircraft

CM127

Grease, YSAS Actuator

(9). Apply film of grease (CM127) to

CM318

Primer

smallest inside diameter of seal

CM731

Lockwire CRES

housing.

(10). With belleville spring, spacer and shims

NOTE: Use YSAS actuator grease (CM127) or

(if installed) in place within end bore of

mix aircraft grease (CM111) and molybde

seal housing, slide seal housing into

num disulfide powder (CM109) to regrease

position over output shaft as originally

the actuator.

oriented.

(1). Prior to applying new grease, re-as

(11). Replace four screws which hold down

semble the output shaft with attached

seal housing; Use only

hardware (splined housing, belleville

NAS1352-04H8P screws.

spring, spacer and shims (if installed))

to the actuator to avoid confusion at

(a). Install screws with wet primer

re-assembly.

(CM318).

(2). Remove and weigh output shaft with

(b). Torque screws to 9 inch-pounds

LVDT core and associated hardware

(1.02 Nm).

attached; Record weight.

(c). Using lockwire (CM731), safety

(3). Adjust scale up 2.5 grams.

screws.

Page 805

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Revision 42

CSP-HMI-2

MD Helicopters, Inc.

MAINTENANCE MANUAL

(12). Re-install rod end, nut and lockwasher

(13). Using lockwire (CM731), safety nut to

with rod end face (surface ``A'') oriented

lockwasher, washer may be oriented

at 90° ±2° with respect to surface ``B''.

with lockwire end up or down.

Torque nut to 170 - 200 inch-pounds

(19.21 - 22.60 Nm).

SPLINED

MOTOR

HOUSING

SEAL

ÉÉÉÉÉ

HOUSING

VDT CORE

OUTPUT

1.10 ± 0.03 IN

SHAFT

(27.9"0.76 MM)

ROD

END

LOCKWASHER

LOCKWIRE

BELLEVILLE

SHIMS

SPRING

SHIMS

SPACERS

SCREW

SAFETY

WIRE

G67-2021

Figure 801. YSAS Actuator (Cross−Section View)

Page 806

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CSP−HMI−2

MAINTENANCE MANUAL

TABLE OF CONTENTS

Para/Figure/Table

Title

Page

71-00-00 Power Plant (250-C20)

Description and Operation

1. Power Plant Description

2. Power Plant Operation

3. Models 250-C20B and 250-C20R/2 Power Plant Fault Isolation

Table 1. Power Plant Fault Isolation

Removal/Installation

401

1. Engine Removal

401

A. Engine Disconnecting for Removal

401

Figure 401. Allison 250-C20B and 250-C20R/2 Engine Removal and

Installation (Sheet 1 of 2)

402

B. Removal of Disconnected Engine

404

2. Engine Installation

404

A. Engine Installation in Mounts

404

B. Connecting an Installed Engine

405

Figure 402. Model 250-C20B and 250-C20R/2 Engine Stripping and

Buildup (Sheet 1 of 2)

406

3. Engine Stripping

408

Figure 403. Model 250-C20B and 250-C20R/2 Engine Mounts and

Airframe Fittings

410

4. Engine Buildup

411

5. Modification of Accessory Drive Gearbox Overboard Vent Tube

(SN 0004D - 0519D)

413

Figure 404. Extension of Engine Accessory Drive Overboard Vent Tube

413

71-00-30 Power Plant (250-C30)

Description and Operation

1. Power Plant Description

2. Power Plant Operation

3. Model 250-C30 Power Plant Fault Isolation

Table 1. Power Plant Fault Isolation

Removal/Installation

401

1. Engine Removal

401

A. Engine Disconnecting for Removal

401

Figure 401. Model 250-C30 Engine Removal and Installation (Sheet 1 of 2) . .

402

B. Removal of Disconnected Engine

404

2. Engine Installation

404

A. Engine Installation in Mounts

404

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MAINTENANCE MANUAL

TABLE OF CONTENTS (Cont.)

Para/Figure/Table

Title

Page

B. Connecting an Installed Engine

405

Figure 402. Engine Mounts and Structural Fittings

406

3. Engine Stripping

407

Figure 403. Model 250-C30 Engine Build-Up (Sheet 1 of 2)

408

4. Engine Buildup

410

71-00-47 Power Plant (250-C47)

Description and Operation

1. Power Plant Description

2. Power Plant Operation

3. Model 250-C47 Power Plant Fault Isolation

Table 1. Power Plant Fault Isolation

Figure 1. Starter/Generator System Wiring Diagram (Sheet 1 of 2)

Figure 2. Engine Wire Harness Wiring Diagram

Removal/Installation

401

1. Model 250-C47 Engine Replacement

401

A. Engine Disconnecting for Removal

401

Figure 401. Engine Build-up Assembly (Sheet 1 of 2)

402

Figure 402. Engine Installation (Sheet 1 of 2)

404

B. Removal of Disconnected Engine

406

C. Engine Installation in Mounts

406

D. Connecting an Installed Engine

407

Figure 403. Starter/Generator Electrical Connections

408

2. Model 250-C47 Engine Stripping

408

3. Model 250-C47 Engine Buildup

409

71-10-00 Engine Air Intake System (369D/E/FF - 500/600N)

Maintenance Practices

201

1. Description and Operation

201

2. Air Inlet Screen Replacement

201

A. Air Inlet Screen Removal (369D/E/FF - 500N)

201

Figure 201. Engine Air Inlet Screen Installation (Sheet 1 of 2)

202

B. Engine Inlet Screen Removal (600N)

204

C. Air Inlet Screen Installation (369D/E/FF - 500N)

204

D. Engine Inlet Screen Installation (600N)

204

3. Air Inlet Bell Replacement

204

A. Air Inlet Bell Removal

204

B. Air Inlet Bell Installation

204

Page ii

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CSP−HMI−2

MAINTENANCE MANUAL

TABLE OF CONTENTS (Cont.)

Para/Figure/Table

Title

Page

4. Firewall Seal Removal

204

5. Air Intake System Inspection

204

Figure 202. Firewall Seal Installation

205

6. Firewall Seal Ring Repair

206

7. Air Inlet Bell Repair

206

8. Plenum Chamber Drain Tube Replacement

206

Figure 203. Drain System

206

71-10-05 Engine Compressor Water Wash Kit (369D/E/FF - 500/600N)

Maintenance Practices

201

1. Engine Compressor Water Wash Kit Maintenance

201

2. Engine Compressor Water Wash Kit Inspection

201

Initial Installation

901

1. Engine Compressor Water Wash Kit Initial Installation

901

A. Gaining Access to Work Area

901

B. Airframe Modification and Installation

901

2. Installation Inspection

901

Figure 901. Engine Compressor Water Wash Kit Installation

(Sheet 1 of 3)

902

71-10-10 Engine Air Particle Separator (369D/E/FF - 500N)

Description and Operation

1. Description and Operation

Table 1. Engine Air Particle Separator Configurations

Figure 1. Particle Separator Operating Principle - Early Type

(Donaldson Unit)

Figure 2. Particle Separator Operating Principle - Current Type

(APM Unit)

Fault Isolation

101

1. Engine Air Particle Separator Fault Isolation

101

Table 101. Engine Air Particle Separator Fault Isolation

101

Figure 101.

369H90148-503, -505, -507, -509 Particle Separator

Installation Wiring Diagram (Slim-Line Panel)

102

Figure 102.

369H90148-503, -505, -507, -509 Particle Separator Installation

Wiring Diagram (T-Panel with Center Console)

103

Figure 103.

369H90148-519, -521, -527, -529 Particle Separator

Installation Wiring Diagram

104

Figure 104.

369H90148-535,-537, -539, -541, -543, -545 and 500N90148-1, -3

Particle Separator Installation Wiring Diagram

105

Maintenance Practices

201

1. Air Bypass Door System Maintenance

201

Page iii

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MD Helicopters, Inc.

MAINTENANCE MANUAL

TABLE OF CONTENTS (Cont.)

Para/Figure/Table

Title

Page

2. Solenoid Air Valve Cleaning

201

3. Air Pressure Sensing Switch Maintenance

202

4. Air Bypass Door Rigging (369D/E/FF)

202

5. Air Bypass Door Rigging (500N)

203

6. Particle Separator Cleaning

203

7. Mist Eliminator Maintenance

203

Figure 201. Air Bypass Door System (369D/E/FF) (Sheet 1 of 3)

204

Figure 202. Air Bypass Door System (500N)

207

Removal/Installation

401

1. PLM Particle Separator Replacement

401

A. PLM Particle Separator Removal

401

B. PLM Particle Separator Installation

401

2. PLM Scavenge Ejector Replacement

401

A. PLM Scavenge Ejector Removal

401

B. PLM Scavenge Ejector Installation

402

3. PLM Ejector Nozzle and Manifold Replacement

402

4. Mist Eliminator Replacement

402

A. Helicopters With Mist Eliminator Access Panel

402

B. Helicopters Without Mist Eliminator Access Panel

402

C. Mist Eliminator Installation

402

5. Donaldson Particle Separator Replacement

402

A. Donaldson Particle Separator Removal

402

B. Donaldson Particle Separator Installation

403

Inspection/Check

601

1. Engine Air Inlet Bypass Door 300-Hour Inspection

601

2. PLM Particle Separator Inspection

601

3. Donaldson Particle Separator Inspection

602

4. Scavenge Air Operational Check

602

5. Air Pressure Sensing Switch Calibration Check

603

6. Mist Eliminator Inspection

603

Figure 601. Air Pressure Sensing Switch Calibration Check

604

Repairs

801

1. PLM Particle Separator Repairs

801

A. Vortex Tube Plug Installation

801

B. Displaced Vortex Generator Tube

801

Figure 801. Vortex Generator Repairs

802

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CSP−HMI−2

MAINTENANCE MANUAL

TABLE OF CONTENTS (Cont.)

Para/Figure/Table

Title

Page

C. Damaged Or Missing Vortex Generator Tube

803

D. Damaged Or Missing Vortex Generator and Outlet Tubes

803

E. PLM Particle Separator Gasket Replacement

803

F. Fairing Modifications (369D Only)

803

Figure 802. Fairing Modifications

804

2. Mist Eliminator Repair

805

3. Particle Separator Alignment and Joint Surface Repair (369D/E/FF)

805

4. Donaldson Particle Separator Repair (369D Only)

805

Figure 803. Donaldson Particle Separator Gasket Replacement

806

Figure 804. Mist Eliminator Bolt Repair

807

5. Donaldson Particle Separator Auxiliary Fairings and Seals Installation

808

Figure 805. Auxiliary Fairings and Seals Installation (Sheet 1 of 2)

810

Figure 806. Auxiliary Fairings and Supports Fabrication (Sheet 1 of 2)

812

Figure 807. Pressure Switch

814

Initial Installation

901

Engine Air Particle Separator Initial Installation

901

A. Filter Bypass Door and Aft Cable

901

Figure 901. Air Bypass Door Installation (Sheet 1 of 2)

902

Figure 902. Aft Cable Installation (Sheet 1 of 2)

904

B. Cover Installation

906

C. Handle and Forward Cable Installation

906

D. Bleed Air System Installation (Helicopters Without Cabin Heat)

907

E. Bleed Air System Installation (Helicopters With Cabin Heat)

907

Figure 903. Handle and Forward Cable Installation (Sheet 1 of 3)

908

F. Scavenge Air System Installation

911

Figure 904. Modifications and Installation (Sheet 1 of 4)

912

G. Solenoid Valve and Pressure Switch Wire Harness Installation

916

Figure 905. Scavenge Air Equipment Installation

917

H. Ejector Duct Doubler and Rib Installation

918

I. Particle Separator Installation

918

Figure 906. Ejector Duct Doubler Installation

919

Figure 907. Wiring Harness Installation

920

J. Instrument Panel Modifications; T-Pedestal

922

K. Slimline Panel Modification

922

L. Post-Installation Inspection

923

M. Weight and Balance

923

Table 901. Weight and Balance Data

923

Page v

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CSP−HMI−2

MD Helicopters, Inc.

MAINTENANCE MANUAL

TABLE OF CONTENTS (Cont.)

Para/Figure/Table

Title

Page

71-10-60 Engine Air Particle Separator (600N)

Description and Operation

1. Description and Operation

Fault Isolation

101

1. Engine Air Particle Separator Fault Isolation

101

Table 101. Engine Air Particle Separator Fault Isolation

101

Figure 101. Air Intake and Particle Separator Circuits Wiring Diagram

101

Removal/Installation

401

Particle Separator Replacement

401

A. Particle Separator Removal

401

B. Particle Separator Installation

401

Scavenge Air Solenoid Valve Replacement

401

A. Scavenge Air Solenoid Valve Removal

401

B. Scavenge Air Solenoid Valve Installation

401

Air Filter Bypass Switch Replacement

401

A. Air Filter Bypass Switch Removal

401

B. Air Filter Bypass Switch Installation

401

Bypass Door Assembly Replacement

401

A. Bypass Door Assembly Removal

401

B. Bypass Door Assembly Installation

401

Bypass Door Cable Assembly Replacement

402

A. Bypass Door Cable Assembly Removal

402

B. Bypass Door Cable Assembly Installation

402

Bypass Door Seal Repair

402

Particle Separator Manifold Replacement

402

Figure 401. Engine Air Particle Separator Installation

403

Figure 402. Bypass Door Installation

404

Inspection/Check

601

1. Engine Air Particle Separator Inspection

601

2. Bypass Door Inspection

601

3. Bypass Door Cable Inspection

601

4. Air Pressure Sensing Switch Calibration Check

601

Figure 601. Air Pressure Sensing Switch Calibration Check

602

71-20-00 Engine Mounts (250-C20B, 250-C20R/2, 250-C30 and 250-C47)

Description and Operation

1. Description

Page vi

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CSP−HMI−2

MAINTENANCE MANUAL

TABLE OF CONTENTS (Cont.)

Para/Figure/Table

Title

Page

2. Airframe Fittings

Removal/Installation

401

1. Airframe Fittings Replacement

401

2. Lower Engine Mount Replacement (250-C20/-C20R/2)

401

A. Lower Engine Mount Removal (250-C20/-C20R/2)

401

B. Lower Engine Mount Installation (250-C20/-C20R/2)

401

3. Upper Engine Mounts Replacement (250-C20/-C20R/2)

401

A. Upper Engine Mounts Removal (250-C20/-C20R/2)

401

B. Upper Engine Mounts Installation (250-C20/-C20R/2)

401

Figure 401. 250-C20/-C20R/2 Engine Mounts and Airframe Fittings

402

4. Lower-Aft Engine Mount Replacement (250-C30/-C47)

403

A. Lower-Aft Engine Mount Removal (250-C30/-C47)

403

B. Lower-Aft Engine Mount Installation (250-C30/-C47)

403

5. Upper Engine Mounts Replacement (250-C30/-C47)

403

A. Upper Engine Mounts Removal (250-C30/-C47)

403

B. Upper Engine Mounts Installation (250-C30/-C47)

403

Figure 402. Model 250-C30/-C47 Engine Mounts and Airframe Fittings

405

Inspection/check

601

1. Engine Mounts and Fittings Inspection

601

2. Upper Engine Mounts Adjustment

601

Repairs

801

1. Engine Mount Repairs

801

2. Mount Hole Repair (250-C20/-20R/2)

801

3. Painted Surfaces Repair

801

71-30-00 Engine Ignition Control System (250-C20B, 250-C20R/2 and 250-C30)

Description and Operation

1. Engine Ignition System Description and Operation

2. Automatic Re-ignition System Description and Operation

Fault Isolation

101

1. Engine Ignition System Fault Isolation

101

Table 101. Ignition System Fault Isolation

101

2. Automatic Re-ignition System Fault Isolation

102

Table 102. Automatic Re-ignition System Fault Isolation (369D)

102

Table 103. Automatic Re-ignition System Fault Isolation (369E/FF - 500N) . .

103

Removal/Installation

401

1. Automatic Re-ignition System Component Replacement

401

Page vii

71 Contents

Revision 36

HANDBOOK OF MAINTENANCE INSTRUCTIONS FOR MDHI 369D/E/FF-500/600N HELICOPTERS (ISSUED: 1990) - page 26