Robinson R-66 Series Lithium-Ion User manual

MAY 2015 Chapter 18 Track and Balance Page 18.i
CHAPTER 18
TRACK AND BALANCE
Section Title Page
18-10 Main Rotor Track and Balance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.1
18-11 Preparing Helicopter for Main Rotor Track and Balance . . . . . . . . . . . . . . 18.3
18-12 Flight Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.5
18-13 Track Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.7
18-14 Balance Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.10
18-15 Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.11
18-16 Autorotational RPM Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.12
18-20 Tail Rotor Dynamic Balance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.17
18-21 Preparing Helicopter for Tail Rotor Dynamic Balance . . . . . . . . . . . . . . . . 18.17
18-22 Ground Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.19
18-23 Balance Adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.19
18-30 Main Rotor Flight Control Rigging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.21
18-40 Main Rotor Blade Angle Rigging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.23
18-41 Collective Travel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.24
18-42 Cyclic Travel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.26
18-50 Tail Rotor Flight Control Rigging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.28
18-51 Pedals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.28
18-52 Forward Bellcrank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.28
18-53 Intermediate Bellcrank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.28
18-60 Tail Rotor Blade Rigging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.29
18-70 Fan Shaft and Engine Shaft Balancing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.33
18-71 Preparing Helicopter for Fan Shaft and Engine Shaft Balancing . . . . . . . . . 18.33
18-72 Ground Checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.34

Intentionally Blank
Page 18.ii Chapter 18 Track and Balance MAY 2015

CHAPTER 18
TRACK AND BALANCE
18-10 Main Rotor Track and Balance
NOTE
Calibrate track and balance equipment per manufacturer's
recommendation, at least once a year, or if equipment is
dropped, misused, or calibration is suspect.
NOTE
The Chadwick-Helmuth Vibrex system, the TEC ACES system,
the Dynamic Solutions Systems’ MicroVib system, or equivalent
equipment is required to perform dynamic rotor balancing and
in-flight track checks.
25 OCT 2010 R66 Maintenance Manual Chapter 18 Track and Balance Page 18.1

FIGURE 18-1 MAIN ROTOR BALANCING EQUIPMENT INSTALLATION
Page 18.2 Chapter 18 Track and Balance R66 Maintenance Manual 25 OCT 2010

25 OCT 2010 R66 Maintenance Manual Chapter 18 Track and Balance Page 18.3
18-11 Preparing Helicopter for Main Rotor Track and Balance
NOTE
Use the following track & balance procedures in conjunction with
approved equipment manufacturer’s balancing instructions.
CAUTION
Cable security is critical; helicopter will be flown at VNE.
1. Perform swashplate and rotor hub inspection per Section 5-45. Inspect tail rotor rod
ends and elastomeric bearings per Sections 5-33 and 5-34.
2. Clean main and tail rotor blades per Section 20-10. Install main rotor blade target tape
per Figure 18-1.
3. Refer to Figure 18-1. Using appropriate hardware, attach brackets to vibration transducer
and attach assembly to F359-1 panel as shown. Remove removable controls.
4. Install magnetic pickup onto swashplate bracket. Set (swashplate-mounted) interrupter-
to-pickup gap to 0.030 inch ± 0.010 inch and tighten pickup nuts against bracket.
Safety nuts using 0.020-inch diameter lockwire. Recheck gap.
5. Pull collective stick full up, push cyclic stick full left, and apply frictions. Connect proper
cable to magnetic pickup. Route cable down seam and to base of mast fairing, across
the cabin roof left side, and through the aft left door vent door. Attach the cable to the
fuselage using MS21919WDG3 clamps and existing fasteners, or secure cable every
12 inches with duct tape. Release control frictions and verify sufficient cable slack and
freedom of controls through full range of travel.
6. Connect proper cable to vibration transducer. Connect transducer, magnetic pickup,
and tracker or strobe cables to analyzer. If strobe light is used, battery power may be
accessed thru auxiliary power socket located on circuit breaker panel. Neatly stow and
secure excess cables.
7. Verify security of installation.

BALANCE TRACK (KNOTS)
CLOCK IPS HOVER 50 60 70 80 90 100 110 120 130 140
I
II II II II II II II II II II I
Adjustment:
CLOCK IPS HOVER 50 60 70 80 90 100 110 120 130 140
I
II II II II II II II II II II I
Adjustment:
CLOCK IPS HOVER 50 60 70 80 90 100 110 120 130 140
I
II II II II II II II II II II I
Adjustment:
CLOCK IPS HOVER 50 60 70 80 90 100 110 120 130 140
I
II II II II II II II II II II I
FIGURE 18-2 MAIN ROTOR TRACK AND BALANCE CHART
TIP WEIGHTS
(1) AN960-10 Washer = (2) AN960-10L Washers
(1) C298-2 Weight = (5) AN960-10 Washers
(1) C298-3 Weight = (11) AN960-10 Washers
(1) C298-4 Weight = (4) C298-3 Weights
CHORD ARM WEIGHTS
(1) A255-1 Weight = (8) AN970-4 Washers
(1) A255-2 Weight = (3) A255-1 Weights
TEETER HINGE SHIMS
C117-8 0.012 inch
C117-9 0.015 inch
C117-10 0.020 inch
C117-11 0.025 inch
DATE SERIAL NO.
PAGE
Page 18.4 Chapter 18 Track and Balance R66 Maintenance Manual 25 OCT 2010

18-12 Flight Checks
NOTE
Run-up and shutdown helicopter throughout procedure as
required per R66 Pilot's Operating Handbook (POH) Section 4.
NOTE
Refer to Section 18-15 for track and balance troubleshooting
procedures.
WARNING
Tail rotor balancing equipment must be removed for flight.
WARNING
Do not exceed VNE of helicopter during flight checks.
1. Prepare helicopter for main rotor track and balance per Section 18-11.
2. Make a photocopy of Figure 18-2; use copy to record flight data. Check main rotor
blade track in a hover and record data. Maximum blade spread in a hover is 0.25 inch.
Adjust track per Section 18-13 as required, record change, and recheck blade track in a
hover. Repeat step as required until blade track is within limits.
3. Check main rotor balance in a hover and record data. Maximum vibration allowance
is 0.2 ips (inches per second). Adjust balance per Section 18-14 as required, record
data, and recheck balance in a hover. Repeat step as required until main rotor balance
is within limits.
4. Fly helicopter at 50, 60, 70, 80, 90, 100, 110, 120, 130, and 140 knots. Check main
rotor blade track at each airspeed and record data. Maximum blade spread between
airspeeds is 3/8 inch. Adjust trim tab(s) per Section 18-13 as required and record data.
Repeat step as required until blade track is within limits.
5. Recheck main rotor balance in a hover per step 3.
6. Perform autorotation RPM check per Section 18-16. Recheck main rotor balance in a
hover per step 3.
7. Evaluate collective trim, longitudinal cyclic trim, and lateral cyclic trim. Adjust as
required. Recheck main rotor balance in a hover per step 3.
8. Remove track and balance equipment. Torque stripe fasteners. Reinstall removable
controls, as required.
25 OCT 2010 R66 Maintenance Manual Chapter 18 Track and Balance Page 18.5

FIGURE 18-3 MAIN ROTOR PITCH LINK
Coarse Length Adjustment
Rod End and Fitting
• One full turn changes blade angle 0.88º.
Medium Length Adjustment
(Upper) Rod End Only
• One-half rod end turn changes blade track 0.25 inch.
• One full rod end turn changes blade angle 0.48º.
Fine Adjustment
Fitting Only
• One full turn changes blade track 0.25 inch.
• One full turn changes blade angle 0.40º.
Page 18.6 Chapter 18 Track and Balance R66 Maintenance Manual 25 OCT 2010

18-13 Track Adjustment
A. Main Rotor Blade Pitch Link
Refer to R66 Illustrated Parts Catalog (IPC) Figure 62-5.
NOTE
Shorten high pitch blade when adjusting track in a hover.
NOTE
During rigging, adjust both pitch links exactly the same for
collective adjustments.
1. Refer to Figure 18-3. For coarse length adjustment, adjust rod end and fitting per
the following steps:
a. Cut and discard pitch link assembly safety wire. Using backup wrench on link
assembly, loosen jam nut in middle of pitch link. Remove hardware securing
upper rod end to blade pitch horn.
b. Rotate rod end and fitting to shorten or lengthen pitch link as required. One full
turn changes blade angle by approximately 0.88°.
c. Refer to Figure 5-1. Verify rod end threaded shank blocks passage of 0.020-inch
diameter lockwire through pitch link witness hole. Install hardware securing rod
end to pitch horn and torque fastener per Section 20-32.
d. Position rod ends to allow as much pitch link rotation as possible without binding.
Using backup wrench on link assembly, torque jam nut per Section 20-32. Safety
fitting to link assembly using 0.032-inch diameter lockwire.
e. Repeat steps on opposite pitch link as required. Torque stripe per Figure 5-1.
2. For medium length adjustment, adjust rod end only per the following steps:
a. Using backup wrench on fitting, loosen upper rod end palnut and jam nut. Remove
hardware securing rod end to blade pitch horn.
b. Rotate rod end to shorten or lengthen pitch link as required. One-half rod end
turn changes blade track approximately 0.25 inch. One full rod end turn changes
blade angle by approximately 0.48°.
c. Refer to Figure 5-1. Verify rod end threaded shank blocks passage of 0.020-inch
diameter lockwire through pitch link witness hole. Install hardware securing rod
end to pitch horn and torque fastener per Section 20-32.
d. Position rod ends to allow as much pitch link rotation as possible without binding.
Using backup wrench on fitting, torque rod end jam nut and palnut per Section
20-32.
e. Repeat steps on opposite pitch link as required. Torque stripe per Figure 5-1.
25 OCT 2010 R66 Maintenance Manual Chapter 18 Track and Balance Page 18.7

FIGURE 18-4 MAIN ROTOR BLADE TRIM TAB
Page 18.8 Chapter 18 Track and Balance R66 Maintenance Manual 25 OCT 2010

18-13 Track Adjustment (continued)
A. Main Rotor Blade Pitch Link (continued)
3. For fine adjustment, adjust fitting only per the following steps:
a. Remove and discard pitch link assembly safety wire. Using backup wrench on
link assembly, loosen jam nut in middle of pitch link. Using backup wrench on
fitting, loosen upper rod end palnut and jam nut.
b. Rotate fitting to shorten or lengthen pitch link as required. One full turn changes
blade track approximately 0.25 inch. One full turn of fitting changes blade
angle approximately 0.40°. For finer adjustment, count hex flats while rotating
fitting.
c. Refer to Figure 5-1. Verify rod end threaded shank blocks passage of 0.020-inch
diameter lockwire through pitch link witness hole.
d. Using backup wrench on link assembly, torque jam nut per Section 20-32. Using
backup wrench on fitting, torque rod end jam nut and palnut per Section 20-32.
Safety fitting to link assembly using 0.032-inch diameter lockwire.
e. Repeat steps on opposite pitch link as required. Torque stripe per Figure 5-1.
B. Main Rotor Blade Trim Tab
NOTE
To correct for a "climbing" blade condition (blade spread that
exceeds 3/8 inch with forward airspeed), bend high blade trim
tab down.
CAUTION
Do not use other helicopter manufacturers' trim tab bending
tools. Use of these tools will damage Robinson blades.
CAUTION
MT352-1 gage must contact trim tab trailing edge. If gage
does not contact tab trailing edge, tab is bent beyond limit.
CAUTION
Tighten MT526-8 bending tool bolt to bend tab; do not use tool
as a lever.
CAUTION
Bend tab upward only when absolutely necessary; bending tab
upward can increase rotor vibration.
1. Using felt tip marker, ink mark main rotor blade trim tab per Figure 18-4. Mark line
with a measuring point in the center of the tab (approximate).
25 OCT 2010 R66 Maintenance Manual Chapter 18 Track and Balance Page 18.9

18-13 Track Adjustment (continued)
B. Main Rotor Blade Trim Tab (continued)
2. Position MT352-1 gage chordwise across blade upper surface and tab trailing edge.
Zero dial indicator on measuring point.
3. Position MT526-8 bending tool on tab per Figure 18-4. Slide tool completely over
tab until tool stops contact blade trailing edge. Double-rib side of tool should contact
tab upper surface to bend tab down. Double-rib side of tool should contact tab
bottom surface to bend tab up.
4. Tighten MT526-8 bending tool bolt to bend tab. Make slight bends and remeasure tab
with MT352-1 gage. Bend trim tab 0.015 inch (down) to effect dynamic movement
of main rotor blade tip approximately 0.2 inch (downward).
18-14 Balance Adjustment
WARNING
A rotor which is smooth after balancing but goes out of balance
within a few flights is suspect and must be examined by RHC
before further flight.
A. Tip Weights (Spanwise Balance Adjustment)
1. Remove screws securing tip cover to blade. Balance rotor assembly spanwise
by adjusting tip weights as required per Figure 18-2. Washers may be trimmed.
Special torque fasteners securing tip weights per Section 20-33. Install tip cover
and standard torque fasteners per Section 20-32.
(1) AN960-10 or NAS1149F0363P Washer = (2) AN960-10L or NAS1149F0332P Washers
(1) C298-2 Weight = (5) AN960-10 or NAS1149F0363P Washers
(1) C298-3 Weight = (11) AN960-10 or NAS1149F0363P Washers
(1) C298-4 Weight = (4) C298-3 Weights
B. Teeter Hinge Bolt Shims (Chordwise Balance Adjustment - Coarse Adjustment)
1. Remove and discard teeter hinge nut cotter pin. Remove nut, thrust washer, and any
shims.
2. Have two people cone the main rotor blades. Push out teeter hinge bolt (and any
shims) with another bolt.
3. Balance rotor assembly chordwise by moving (or exchanging) existing teeter hinge
shims to other side of bolt (under head or under nut) as required per Figure 18-2.
Install teeter hinge bolt per Section 62-10.
C. Chord Arm Weight (Chordwise Balance Adjustment - Fine Adjustment)
1. Balance rotor assembly chordwise by adjusting chord arm weights or washers per
Figure 18-2. Total weight not to exceed four A255-2 weights (or equivalent).
(1) A255-1 Weight = (8) AN970-4 Washers
(1) A255-2 Weight = (3) A255-1 Weights
Page 18.10 Chapter 18 Track and Balance R66 Maintenance Manual 25 OCT 2010

18-13 Track Adjustment (continued)
B. Main Rotor Blade Trim Tab (continued)
2. Position MT352-1 gage chordwise across blade upper surface and tab trailing edge.
Zero dial indicator on measuring point.
3. Position MT526-8 bending tool on tab per Figure 18-4. Slide tool completely over
tab until tool stops contact blade trailing edge. Double-rib side of tool should contact
tab upper surface to bend tab down. Double-rib side of tool should contact tab
bottom surface to bend tab up.
4. Tighten MT526-8 bending tool bolt to bend tab. Make slight bends and remeasure tab
with MT352-1 gage. Bend trim tab 0.015 inch (down) to effect dynamic movement
of main rotor blade tip approximately 0.2 inch (downward).
18-14 Balance Adjustment
WARNING
A rotor which is smooth after balancing but goes out of balance
within a few flights is suspect and must be examined by RHC
before further flight.
A. Tip Weights (Spanwise Balance Adjustment)
1. Remove screws securing tip cover to blade. Balance rotor assembly spanwise
by adjusting tip weights as required per Figure 18-2. Washers may be trimmed.
Special torque fasteners securing tip weights per Section 20-33. Install tip cover
and standard torque fasteners per Section 20-32.
(1) AN960-10 or NAS1149F0363P Washer = (2) AN960-10L or NAS1149F0332P Washers
(1) C298-2 Weight = (5) AN960-10 or NAS1149F0363P Washers
(1) C298-3 Weight = (11) AN960-10 or NAS1149F0363P Washers
(1) C298-4 Weight = (4) C298-3 Weights
B. Teeter Hinge Bolt Shims (Chordwise Balance Adjustment - Coarse Adjustment)
1. Remove and discard teeter hinge nut cotter pin. Remove nut, thrust washer, and any
shims.
2. Have two people cone the main rotor blades. Push out teeter hinge bolt (and any
shims) with another bolt.
3. Balance rotor assembly chordwise by moving (or exchanging) existing teeter hinge
shims to other side of bolt (under head or under nut) as required per Figure 18-2.
Install teeter hinge bolt per Section 62-10.
C. Chord Arm Weight (Chordwise Balance Adjustment - Fine Adjustment)
1. Balance rotor assembly chordwise by adjusting chord arm weights or washers per
Figure 18-2. Total weight not to exceed four A255-2 weights (or equivalent).
(1) A255-1 Weight = (8) AN970-4 Washers
(1) A255-2 Weight = (3) A255-1 Weights
18-15 Troubleshooting
The following are some of the symptoms and corrections which occur in the Track and Balance
operations of the helicopter. Decide on the various causes of a given trouble and then eliminate
causes one by one, beginning with the most probable.
Symptom Probable Cause Correction
1. Excessive Cyclic or
Stick Shake Main rotor (MR) out of track. Track and balance per Section 18-10.
Rough or binding A205-7 fork
assembly (upper swashplate). Replace or refer to Section 67-40.
Brinelled spindle bearing
(rough movement). Send blade(s) to RHC for spindle bearing replacement.
Rough blade surface (chipped paint). Repair blades per Section 62-60.
Rough or binding pitch links. Replace pitch link rod ends
MR blade boot misaligned. Realign or replace boot per Section 62-11.
MR teeter or coning hinge binding. Replace bearings per Section 62-21.
MR blade trim tabs bent upward. Bend trim tabs evenly down per Section 18-13.
Blade mismatch. Send blade(s) to RHC for replacement.
2. Excessive Ship
Vibration MR out of track and balance. Track and balance per Section 18-10.
MR teeter or coning hinge friction. Adjust hinge friction per Section 62-32.
MR teeter or coning hinge binding. Replace bearings per Section 62-21.
Brinelled spindle bearing
(rough movement). Send blade(s) to RHC for spindle bearing replacement.
MR teeter hinge bearings worn. Replace bearings per Section 62-21.
3. Excessive Cyclic
Stick Forces Brinelled spindle bearing (rough movement). Send blade(s) to RHC for spindle bearing replacement.
4. Intermittent Blade
Track Picture MR teeter or coning hinge friction Adjust hinge friction per Section 62-32.
MR coning hinge binding. Replace bearings per Section 62-21.
MR teeter hinge not "broken-in." Track and balance per Section 18-10. Adjust
track to minimize error.
Brinelled spindle bearing
(rough movement). Send blade(s) to RHC for spindle bearing replacement.
5. Radical Changes to
Cyclic Trim MR teeter hinge bearings worn. Replace bearings per Section 62-21.
Brinelled spindle bearing
(rough movement). Send blade(s) to RHC for spindle bearing replacement.
25 OCT 2010 R66 Maintenance Manual Chapter 18 Track and Balance Page 18.11

18-16 Autorotational RPM Adjustment
Use the following procedure for checking and adjusting autorotational RPM:
WARNING
Failure to properly adjust autorotational RPM (RPM too low)
may prevent the rotorcraft from achieving proper RPM at low
gross weights.
1. Perform autorotation RPM check at minimum practical gross weight (less than 1900
lb). Calculate the takeoff gross weight of the helicopter. Record the time on the
hourmeter.
Take-Off gross weight:
Take-Off hourmeter reading:
2. Set the altimeter to 29.92” Hg (1013.2 millibars) prior to performing the autorotation.
Autorotate with the collective control firmly held against the down stop with an airspeed
of 50 KIAS.
WARNING
Do not allow the rotor to overspeed when performing autorotation
checks. Progressively lengthen both main rotor pitch link rod
ends until full down collective can be obtained without over-
speeding the rotor.
Take at least 3 RPM readings at 500 to 1000 foot altitude intervals.
Record the following in-flight data:
Test # Hourmeter Reading OAT Pressure Altitude Test % RPM
1
2
3
4
5
Page 18.12 Chapter 18 Track and Balance R66 Maintenance Manual 25 OCT 2010

18-16 Autorotational RPM Adjustment (continued)
3. After test flight, determine the following:
Test # 12345
Elapsed Time (in-ight hourmeter reading
minus take-off hourmeter reading):
Pounds of Fuel Consumed
(elapsed time x 140 lb/hr):
Test Gross Weight
(take-off gross weight minus fuel consumed):
Test Longitudinal Center of Gravity:
Chart % RPM*:
Test % RPM (from in-ight data):
RPM Correction
(chart % RPM minus test % RPM):
*Perform step 4 to obtain value.
4. Refer to Figure 18-5. To find Chart % RPM, perform the following:
a. Start at outside air temperature, and draw a vertical line up to pressure altitude.
b. Draw a horizontal line from pressure altitude to rotorcraft gross weight at time of
autorotation.
c. Draw a vertical line down from autorotation gross weight to required auto RPM.
5. Adjust pitch links based on average RPM correction required. Lengthen both pitch links
to decrease RPM if test RPM is greater than chart RPM; shorten both pitch links to
increase RPM. One full rod end turn will change RPM approximately 3½%. Adjust both
pitch links exactly the same so track will not be affected.
6. Repeat previous steps as required until the RPM correction is ± 1% of chart RPM.
25 OCT 2010 R66 Maintenance Manual Chapter 18 Track and Balance Page 18.13

AUTOROTATION RPM
COLLECTIVE FULL DOWN
50 KIAS
One full turn of rod ends = approximately 3½% RPM change
One full turn of rod end = 1⅙ turns of barrel
Example: OAT=20°C, Hp=2000 ft, GW=1800 lb, RPM=103%
FIGURE 18-5 AUTOROTATION RPM ADJUSTMENT
Page 18.14 Chapter 18 Track and Balance R66 Maintenance Manual 25 OCT 2010

Intentionally Blank
25 OCT 2010 R66 Maintenance Manual Chapter 18 Track and Balance Page 18.15

FIGURE 18-6 TAIL ROTOR BALANCING EQUIPMENT INSTALLATION
Page 18.16 Chapter 18 Track and Balance R66 Maintenance Manual 25 OCT 2010

18-20 Tail Rotor Dynamic Balance
NOTE
Calibrate track and balance equipment per manufacturer's
recommendation, at least once a year, or if equipment is
dropped, misused, or calibration is suspect.
NOTE
The Chadwick-Helmuth Vibrex system, the TEC ACES system,
the Dynamic Solutions Systems’ MicroVib system, or equivalent
equipment is required to perform dynamic rotor balancing and
in-flight track checks.
18-21 Preparing Helicopter for Tail Rotor Dynamic Balance
NOTE
Use the following balance procedures in conjunction with
approved equipment manufacturer’s balancing instructions.
WARNING
Ensure cable(s) cannot entangle tail rotor.
1. Clean tail rotor blades per Section 20-10. Inspect tail rotor rod ends and elastomeric
bearings per Sections 5-33 and 5-34.
2. Track tail rotor blades per Section 64-10.
3. Refer to Figure 18-6. If using photocell to obtain clock angle, install a target tape
spanwise on inboard side of one arm of tail rotor hub; if using Strobex, install a target
tape spanwise on outboard side of hub.
4. Using appropriate hardware, attach bracket(s) to vibration transducer, and photocell, if
used. Secure bracket to tail rotor gearbox output shaft cap at forward, top attachment
bolt. Orient vibration transducer vertically.
5. Connect cable(s) to transducer, and photocell, if used. Route cable(s) forward and into
cabin; wrap around tailcone several times, and secure with duct tape. If using Strobex,
route cable to a position located approximately 20 feet to left of tail rotor. Place
sandbags (or similar) on cable to prevent cable movement.
6. Connect cable(s) to balancer. Verify security of installation.
SEP 2012 R66 Maintenance Manual Chapter 18 Track and Balance Page 18.17

FIGURE 18-7 TAIL ROTOR DYNAMIC BALANCE CHART
DATE SERIAL NO.
PAGE
BLADE-TO-HUB OUTBOARD FASTENER (SPANWISE) WEIGHTS
(1) C141-23 Washer = (3.5) NAS1149F0663P Washers
(1) C141-24 Washer = (7) NAS1149F0663P Washers
(2) NAS1149F0632P (1) NAS1149F0663P Washer
BALANCE
CLOCK IPS
ADJUSTMENT:
CLOCK IPS
ADJUSTMENT:
CLOCK IPS
ADJUSTMENT:
CLOCK IPS
ADJUSTMENT:
PITCH HORN-TO-PITCH LINK FASTENER (CHORDWISE) WEIGHTS
(1) NAS1149F0463P Washer = (2) NAS1149F0432P Washers
(1) A214-3 Washer = (3.5) NAS1149F0432P Washers
(1) A141-14 Washer = (5) NAS1149F0432P Washers
Page 18.18 Chapter 18 Track and Balance R66 Maintenance Manual SEP 2012