ASB MBB BK117 C-2-67A-012

Revison 0, 2010-09-20 PAGE 1 of 10

Valid for Version(s): All.

ALERT SERVICE BULLETIN

SUBJECT: ROTOR FLIGHT CONTROL – Rigging of the main rotor controls

Verify the correct adjustment of the main rotor controls.

Revision No. Date of issue

Revision 0 20100920

Summary:

During rigging of the main rotor controls of one helicopter it has been detected that the piston of the

longitudinal main rotor actuator moved after shut-down of the external pump drive. If unnoticed, such

movements could cause incorrect rigging results. This might impair the helicopter’s controllability and

the freedom of movement of the upper controls. This Alert Service Bulletin requests a one-time

verification of the rigging and provides the corresponding test procedure. An improved rigging

procedure is provided as temporary revision 12b of the AMM as annex to this Alert Service Bulletin.

Compliance:

Compliance with this Alert Service Bulletin is mandatory. See Section 1.E.1 and 1.E.2.

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1. PLANNING INFORMATION

1.A. EFFECTIVITY

1.A.1. Helicopters/installed equipment

MBB BK117 C-2, all models, S/N 9004 up to and including S/N 9400.

1.A.2. Non-installed equipment

Not applicable.

1.B. ASSOCIATED REQUIREMENTS

Not applicable.

1.C. REASON

During rigging of the main rotor controls of one helicopter, it has been detected that the piston

of the longitudinal main rotor actuator moved after shut-down of the external pump drive.

If unnoticed, such movements could cause incorrect rigging results: the control range of the main

rotor could be shifted. In case of unnoticed movement of the power piston of the longitudinal

actuator, the control range could be shifted in longitudinal push direction and thus reduce the

control margin in longitudinal pull. In case of unnoticed movement of the power piston of the

lateral actuator, the control range could be shifted in lateral left and thus reduce the control

margin in lateral right. This might impair the helicopter’s controllability and the freedom of

movement of the upper controls.

To prevent the consequences of possible unnoticed movements of hydraulic power pistons in

the cyclic axes, this Alert Service Bulletin specifies a one-time verification of the adjustment of

the main rotor controls.

1.D. DESCRIPTION

Check rigging of main rotor controls.

1.E. COMPLIANCE

1.E.1. Compliance at the works

Helicopters/installed equipment:

Verify rigging of the power boosted section of the main rotor controls i.a.w. Section 3.B.1 of

this Alert Service Bulletin before delivery of the helicopter.

Non-installed equipment:

Not applicable.

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ASB MBB BK117 C-2-67A-012

Revison 0, 2010-09-20 PAGE 3 of 10

1.E.2. Compliance in service

Helicopters/installed equipment:

(a) Verify rigging of the power boosted section of the main rotor controls i.a.w. Section 3.B.1

of this Alert Service Bulletin within the next 300 Fh (+30 Fh tolerance) after receipt of this

Alert Service Bulletin, but by September 30, 2011 at the latest.

(b) The rigging of the main rotor controls has to be done i.a.w. Temporary Revision 12b of

the AMM (until this TR is included in the regular AMM).

Non-installed equipment:

Not applicable.

1.F. APPROVAL

Approval of the modification(s):

Not applicable.

Approval of the document:

The technical content of this document is approved under the authority of

DOA No. EASA.21J.034

1.G. MANPOWER

Qualification Mechanic Electrician Pilot Others

Rigging of the main

rotor controls

approx. 8 h − − −

1.H. WEIGHT AND BALANCE

Not applicable.

1.I. EFFECT ON ELECTRICAL LOADS

Not applicable.

1.J. SOFTWARE MODIFICATION EMBODIMENT RECORD

Not applicable.

1.K. REFERENCES

AMM MBB BK117 C-2.

1.L. OTHER DOCUMENTS AFFECTED

The changes to AMM/MSM MBB BK117 C-2 which are required as a result of this Alert Service

Bulletin will be incorporated with Temporary Revision 12b.

1.M.INTERCHANGEABILITY OR MIXABILITY OF PARTS

Not applicable.

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PAGE 4 of 10 Revison 0, 2010-09-20

2. Material Information

2.A. MATERIAL: PRICE – AVAILABILITY – PROCUREMENT

Not applicable.

2.B. INFORMATION CONCERNING INDUSTRIAL SUPPORT

Not applicable.

2.C. MATERIAL REQUIRED FOR EACH HELICOPTER/ENGINE/COMPONENT

Not applicable.

2.D. MATERIAL TO BE RETURNED

Not applicable.

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Revison 0, 2010-09-20 PAGE 5 of 10

3. ACCOMPLISHMENT INSTRUCTIONS

3.A. GENERAL

Not applicable.

3.B. OPERATIONAL PROCEDURE

3.B.1. Procedure

(a) Job Set–up

WARNING

MAKE SURE THAT NOBODY STARTS THE 

ENGINES OR MOVES THE FLIGHT CONTROLS 

ACCIDENTALLY.

CAUTION

DO NOT OPERATE THE EXTERNAL PUMP DRIVE

FOR MORE THAN 15 MINUTES. OTHERWISE THE

PUMP DRIVE CAN BE DESTROYED.

1 Remove the crest cowling i.a.w. AMM, 71-11-00, 4-1.

2 Remove the transmission cowlings i.a.w. AMM, 71-11-00, 4-3.

3 Remove the center fairing i.a.w. AMM, 71-11-00, 4-2.

4 Install the External Pump Drive (220 V) L135M2901101 or External Pump Drive

(110V) L135M2905101 and the Adaptor Kit for External Pump Drive B290P0001101

on the LH hydraulic pump i.a.w. AMM, 29-00-00, 2-1.

5 Energize the electrical system i.a.w. AMM, 24-00-00, 2-1.

6 Remove the rotating control rods i.a.w. AMM, 62-32-00,4-1.

7 Install the Dummy Rod Kit B670P4007101 i.a.w. AMM, 62-32-00, 4-1. 

Alternatively do the following:

– Remove the rotating control rods (2, Figure 1) i.a.w. AMM, 63-32-00, 4-1 and

measure and record the length “X” of each rotating control rod i.a.w. AMM,

62-32-00, 4-2.

– Adjust the length of the rotating control rods (2) to 284.0 mm (11.18 in) i.a.w.

AMM, 62-32-00, 4-2.

– Install the rotating control rods (2) i.a.w. AMM, 62-32-00, 4-1.

8 Disconnect the aft end of the control rods/SEMA rods in non–boosted section i.a.w.

AMM, 67-10-00, 4-2 and loosen the clamps. Move the control rods/SEMA rods

upwards out of the way and secure them with clamp straps (see Figure 2).

9 Turn the rotor head until the control rods (2, Figure 1) (with the green and yellow color)

are exactly above the short control rods (1) of the mixing lever assembly.

10 Apply the rotor brake.

11 Install the Rigging Device (3) and fix it.

12 Adjust the “Collective–6.2°”, “lateral left” and “longitudinal push” of the power-boosted

control systems as follows:

– Set the switch on the External Pump Drive (220V) or External Pump Drive (110V)

to the “ON” position.

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PAGE 6 of 10 Revison 0, 2010-09-20

– Manually move the input lever of the longitudinal actuator (RH side) in flight

direction (forwards) with your hand (piston fully extended) and use a clamp strap

to hold it against the mechanical stop ( , Figure 2).

– Manually move the input lever of the lateral actuator (LH side) against flight

direction (rearwards) with your hand (piston fully retracted) and use a clamp strap

to hold it against the mechanical stop ( , Figure 2).

– Manually move the input lever of the collective actuator (center) in flight direction

(forwards) with your hand (piston fully extended) and use a clamp strap to hold

it against the mechanical stop.

– Clean the sliding sleeve and the support tube in the area where the Gauge Block

will be positioned and install the Gauge Block “Collective–6.2°“ (5, Figure 1)

between the sliding sleeve (4) and the support tube (6). Do not touch the actuator

input levers while doing that. Remove the clamp strap that holds the piston of the

collective actuator (center) and slowly move the collective control until the gauge

block is clamped between sliding sleeve and the support tube. Attach the clamp

strap to hold the collective control position against the gauge block (in piston

retract direction , Figure 2).

(b) Check the rigging of the power-boosted control system as follows:

NOTE

Make sure that the piston of the longitudinal actuator (RH side) is still held in

the fully extended position against the mechanical stop.

Make sure that the piston of the lateral actuator (LH side) is still held in the

fully retracted position against the mechanical stop. 

Make sure that the Gauge Block is still clamped between the sliding sleeve

and the support tube.

1 Insert the rigging wedges with the 25.4° (8, Figure 1) and 19.5° (7) markings in the

“A” side of the guide grooves of the Rigging Device (3).

a If the gap between rigging wedges (7, 8) and the inner sleeves (9) is closed (see

picture in Figure 1), the rigging is correct.

b If there is a non-parallel gap between the rigging wedges (7, 8) and the inner

sleeves (9) the rigging is not correct:

– Inspect the power-boosted control system i.a.w. AMM, 67-13-00, 6-1, AMM,

62-31-00, 6-1, AMM, 62-32-00, 6-1 and AMM, 62-33-00, 6-1.

– Perform the rigging procedure according to AMM, 67-00-00, 5-1 (TR12b or newer

version).

(c) Close–up:

1 Remove all clamp straps.

2 Remove the rigging wedges from the rigging device.

3 Remove the clamp strap from the collective actuator (center). Move the collective

actuator by hand in extend direction to release the Gauge Block “Collective–6.2°”.

Remove the Gauge Block.

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Revison 0, 2010-09-20 PAGE 7 of 10

4 Set the switch on the External Pump Drive (220 V) L135M2901101 or External Pump

Drive (110 V) L135M2905101 to the “OFF” position.

5 Remove the rigging device.

6 Remove the Dummy Rod Kit in accordance with AMM, 62-32-00, 4-1 or if you have

alternatively adjusted the original rotating control rods, do the following:

a Remove the rotating control rods i.a.w. AMM, 62-32-00, 4-1.

b Adjust each rotating control rod to its original length “X” i.a.w. AMM, 62-32-00, 4-2.

c Safety the locknuts with new lockwire and apply Silicon rubber (CM 6062) over

them.

7 Install the rotating control rod i.a.w. AMM, 62-32-00, 4-1.

8 Install the control rod/SEMA rods in non–boosted section i.a.w. AMM, 67-10-00, 4-2.

Reinstall clamps (see , Figure 2).

9 Set the switch on the External Pump Drive (220 V) L135M2901101 or External Pump

Drive (110 V) L135M2905101 to the “ON” position.

10 Check all control functions by moving the stick and collective lever through the entire

control range. Check for clearance in all control and rotor head positions.

11 Set the switch on the External Pump Drive (220 V) L135M2901101 or External Pump

Drive (110 V) L135M2905101 to the “OFF” position.

12 Remove the External Pump Drive (220 V) L135M2901101 or External Pump Drive

(110 V) L135M2905101 and Adaptor Kit for External Pump Drive B290P0001101 from

the LH hydraulic pump, i.a.w. AMM, 29-00-00, 2-1.

13 De–energize the electrical system i.a.w. AMM, 24-00-00, 2-1.

14 Remove all tools and other materials and clean the work area.

15 Install the center fairing i.a.w. AMM, 71-11-00, 4-2.

16 Install the transmission cowlings i.a.w. AMM, 71-11-00, 4-3.

17 Install the crest cowling i.a.w. AMM, 71-11-00, 4-1.

18 Copy reply form sheet on page 10, fill it out and send it to ECD customer support.

3.C. Identification

Identification of this document:

Confirm accomplishment of this Alert Service Bulletin by an entry in the historical record of the

helicopter.

3.D. OPERATING AND MAINTENANCE INSTRUCTIONS

Operating Instructions:

Not applicable.

Maintenance instructions:

The revised procedure of the AMM (TR12b) is enclosed to this Alert Service Bulletin.

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ASB MBB BK117 C-2-67A-012

PAGE 8 of 10 Revison 0, 2010-09-20

Installation of gauge block and rigging device

Figure 1

1 Short Control Rod

2 Rotating Control Rod

3 Rigging Device B670P4001101

4 Sliding sleeve

5 Gauge block

6 Support tube

7 Rigging wedge 19.5°

8 Rigging wedge 25.4°

9 Inner sleeve

1

A

2

View A

3

4

5

6

(25.4°)

(19.5°)

3

7

8

9

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Revison 0, 2010-09-20 PAGE 9 of 10

Check of the rigging

Figure 2

1

Move control rods / SEMA upwards.

Clamp loosened.

Longitudinal actuator (hold with clamp strap (1) forwards).

Lateral actuator (hold with clamp strap (1) rearwards).

Collective actuator (with clamp strap (1) pulling rearward

(rigging configuration)).

1 1

4. APPENDIX

Temporary Revison 12b

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ASB MBB BK117 C-2-67A-012

PAGE 10 of 10 Revison 0, 2010-09-20

Telefax

To

Eurocopter Deutschland GmbH

Customer Support

FAX 0049 906 714111

e-mail: Vehicle.ecd.technical-support@eurocopter .com

Address of operator:

Reply form sheet for ASB MBB BK117 C-2-67A-012 ”Rigging of the main rotor

controls”

Please completely fill out reply form sheet and send it to the given FAX No. / e-mail.

Date:__________ Signature:___________________

Please copy page! Original page remains in Alert Service Bulletin!

Helicopter S/N:

Flight hours (fh):

Main rotor controls checked:

Main rotor controls OK.

Main rotor controls adjusted:

comment

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