Leonardo S.p.A.
Via Giovanni Agusta, 520
21017 Cascina Costa di Samarate (VA) Italy
Tel.: +39 0331 229111 - Fax: +39 0331 229605/222595
SERVICE BULLETIN
N° 109-158
ALERT DATE: March 21, 2023
REV. : / - March 15, 2017
TITLE
ATA 64 – TAIL ROTOR HOUSING AND SLIDER GROUP DISASSEMBLY AND
REASSEMBLY
REVISION LOG
First Issue
An appropriate entry should be made in the aircraft log book upon accomplishment.
If ownership of aircraft has changed, please, forward to new owner.
Page 1 of 24
1. PLANNING INFORMATION
A. EFFECTIVITY
Part I:
All A109C helicopters that have performed maintenance activities requiring the
disassembly of the tail rotor duplex bearing housing after the helicopter delivery.
Part II:
All A109C helicopters.
B. COMPLIANCE
Part I:
Within and not later than 100 (one hundred) flight hours or 6 (six) months, whichever
occurs first, after the issue of this Service Bulletin.
Part II:
At each assembly of the tail rotor duplex bearing housing.
C. CONCURRENT REQUIREMENTS
N.A.
D. REASON
This Service Bulletin is issued in order to prescribe the disassembly and reassembly of
the housing and slider assembly of the tail rotor rotating controls.
E. DESCRIPTION
There have been reported cases of ring-nut tighten loss, likely as a result of poor
maintenance tasks accomplishment of the assembly instructions for the tail rotor
housing and slider group.
In order to minimize the likelihood of occurrence of potential human errors during
maintenance, LH updated the maintenance instructions in order to provide additional
guidelines, including a better identification Vital Points (VP) for the assembly of the tail
rotor duplex bearing support.
As such, this Service Bulletin requires (Part I) to perform the installation of the tail rotor
duplex bearing housing following the IETP updated instructions and (Part II) requires to
follow such updated instructions whenever the TR duplex bearing housing is assembled.
During the procedure, the operator must obey the Local Regulations applicable to the
Vital Points. Interactive Electronic Technical Publications (IETP)
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F. APPROVAL
The technical content of this Service Bulletin is approved under the authority of DOA nr.
EASA.21.J.005.
EASA states mandatory compliance with inspections, modifications or technical
directives and related time of compliance by means of relevant Airworthiness Directives.
G. MANPOWER
To comply with this Service Bulletin, the following MMH are deemed necessary:
Part I: 8 (eight).
Part II: N.A.
MMH are based on hands-on time and can change with personnel and facilities available.
H. WEIGHT AND BALANCE
N.A.
I. REFERENCES
1) PUBLICATIONS
SECTION/PARAGRAPH DESCRIPTION PART
PAR01 00-20-1 Helicopter Safety I
PAR02 64-00-12 Tail rotor hub and blades I
assembly – Removal/Installation
PAR03 64-30-3 Pitch change mechanism – I, II
Removal/Installation
2) ACRONYMS & ABBREVIATIONS
AMDI Aircraft Material Data Information
MM Maintenance Manual
DOA Design Organization Approval
IETP Interactive Electronic Technical Publications
EASA European Aviation Safety Agency
LH Leonardo Helicopters
PTUM Pictorial Tools Usage Manual
MMH Maintenance Man Hours
P/N Part Number
S/N Serial Number
3) ANNEX
Annex A MM Section 64-30 Rev. 5
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J. PUBLICATIONS AFFECTED
N.A.
K. SOFTWARE ACCOMPLISHMENT SUMMARY
N.A.
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2. MATERIAL INFORMATION
A. REQUIRED MATERIALS
1) PARTS
N.A.
2) CONSUMABLES
Refer also to AMDI for the consumable materials required to comply with the MM
Paragraphs referenced in the accomplishment instructions.
3) LOGISTIC MATRIX
N.A.
B. SPECIAL TOOLS
Refer to PTUM for the special tools required to comply with the MM Paragraphs
referenced in the accomplishment instructions.
C. INDUSTRY SUPPORT INFORMATION
N.A.
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3. ACCOMPLISHMENT INSTRUCTIONS
GENERAL NOTES
a) Place an identification tag on all components that
are re-usable, including the attaching hardware that
have been removed to gain access to the
modification area and adequately protect them until
their later re-use.
b) Shape the cables in order to prevent interference
with the structure and the other existing installations,
using where necessary suitable lacing cords and
plastic cable tiedown.
PART I
1. In accordance with MM Paragraph 00-20-1, prepare the helicopter on ground for a safe
maintenance. Disconnect the battery, all electrical power sources and/or the external
power supply.
2. In accordance with MM Paragraph 64-00-12, remove from the helicopter the tail rotor hub
and blades assembly.
3. In accordance with MM Paragraph 64-30-3, remove the tail rotor pitch change mechanism.
4. In accordance with MM Paragraph 64-30-3, disassemble the tail rotor housing and slider
assembly.
NOTE
Vital Point (VP): the point of a component, assembly or
installation, where incorrect assembly or an undetected
error could cause the loss of rotorcraft and/or fatalities.
5. In accordance with MM Paragraph 64-30-3 Rev. 5 (Ref. Leonardo WebPortal or Annex A
of this Service Bulletin), assemble the tail rotor housing and slider assembly.
6. In accordance with MM Paragraph 64-30-3, install the tail rotor housing and slider
assembly.
7. In accordance with MM Paragraph 64-00-12, install on the helicopter the tail rotor hub and
blades assembly.
8. Return the helicopter to a ready to flight condition and record for compliance with Part I of
this Service Bulletin on the helicopter logbook.
9. Send the attached compliance form to the following mail box:
engineering.support.lhd@leonardo.com
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As an alternative, gain access to My Communications section on Leonardo WebPortal and
compile the “Service Bulletin Application Communication”.
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DATE: March 21, 2023
REVISION: / Page 7 of 24
PART II
NOTE
Vital Point (VP): the point of a component, assembly or
installation, where incorrect assembly or an undetected
error could cause the loss of rotorcraft and/or fatalities.
1. During the application of any maintenance operation requiring the assembly of the TR
duplex bearing housing, it is required to perform the relevant assembly procedure in
accordance with MM Paragraph 64-30-3 Rev. 5 (Ref. Leonardo WebPortal or Annex A of
this Service Bulletin) or later published issues.
2. Record for compliance with Part II of this Service Bulletin on the helicopter logbook.
3. Send the attached compliance form to the following mail box:
engineering.support.lhd@leonardo.com
As an alternative, gain access to My Communications section on Leonardo WebPortal and
compile the “Service Bulletin Application Communication”.
Non cancellare mai questo segnalibro Non cancellare mai interruzione sezione
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ANNEX A
ANNEX A
MM SECTION 64-30 REV. 5
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ANNEX A
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ANNEX A
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ANNEX A
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ANNEX A
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ANNEX A
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ANNEX A
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ANNEX A
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ANNEX A
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ANNEX A
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ANNEX A
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ANNEX A
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ANNEX A
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ANNEX A
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Please send to the following address:
SERVICE BULLETIN COMPLIANCE FORM Date:
LEONARDO S.p.A.
CUSTOMER SUPPORT & SERVICES - ITALY Number:
PRODUCT SUPPORT ENGINEERING & LICENSES DEPT.
Via Giovanni Agusta, 520
21017 Cascina Costa di Samarate (VA) - ITALY Revision:
Tel.: +39 0331 225036 Fax: +39 0331 225988
Customer Name and Address: Telephone:
Fax:
B.T. Compliance Date:
Helicopter Model S/N Total Number Total Hours T.S.O.
Remarks:
Information:
We request your cooperation in filling this form, in order to keep out statistical data relevant to aircraft configuration up-to-date. The form should be filled in all
its parts and sent to the above address or you can communicate the application also via Technical Bulletin Application Communication Section placed in
Leonardo AW Customer Portal - MyCommunications Area. We thank you beforehand for the information given.
