AD 2011-17-14

final rule

Airworthiness Directives; Agusta S.p.A. Model A109A and A109AII Helicopters

AD Number
2011-17-14
Status
final_rule
Effective Date
Product Category
aircraft
Docket
Docket No. FAA-2011-0861
FR Citation
76 FR 53312
Technical illustration of a helicopter rotor hub assembly
Problem area Rotor system

Applicability

TypeManufacturerModelDetails
aircraft Agusta S.p.A. A109A Airworthiness Directives; Agusta S.p.A. Model A109A and A109AII Helicopters
aircraft Agusta S.p.A. A109A II Airworthiness Directives; Agusta S.p.A. Model A109A and A109AII Helicopters

Unsafe Condition

An improperly torqued hub plug, part number 109-0133-18-103, could lead to tail rotor failure and subsequent loss of control of the helicopter.

AI-generated summary from the source AD text. Verify against the official source before acting.

Required Actions

Inspect the tightening torque value of the hub plug. If between 600 kgcm and 700 kgcm, replace the lock washer and o-ring. If greater than 700 kgcm, replace the hub plug and torque it to the specified range. If less than 600 kgcm, disassemble the tail rotor hub and blades assembly and inspect for damage, replacing any unairworthy parts.

AI-generated summary from the source AD text. Verify against the official source before acting.

Compliance Time

Within 5 hours time-in-service (TIS) or 8 days, whichever occurs first.

AI-generated summary from the source AD text. Verify against the official source before acting.

Affected Aircraft

Agusta S.p.A. Model A109A and A109AII helicopters with a certain tail rotor special hub plug installed.

AI-generated summary from the source AD text. Verify against the official source before acting.

Federal Register Abstract

This amendment adopts a new airworthiness directive (AD) for the specified Agusta S.p.A. (Agusta) helicopters with a certain tail rotor special hub plug (hub plug) installed. This action requires a one-time inspection to determine the tightening torque value of the hub plug, and depending on the inspection results, replacing certain parts or disassembling the tail rotor hub and blades assembly and inspecting for damage. If the tightening torque value is between 600 kgcm and 700 kgcm, the lock washer and o-ring must be replaced with airworthy parts, and no further action is required. If the tightening torque value is greater than 700 kgcm, the hub plug must be replaced with an airworthy part. Torque the new hub plug to the specified tightening torque between 600 and 700 kgcm. If the tightening torque value of the hub plug is less than 600 kgcm, the tail rotor hub and blades assembly must be disassembled and inspected for damage. If a part is found that is outside allowable damage tolerances, that part must be replaced with an airworthy part. This amendment is prompted by the discovery that a wrong tightening torque value for the hub plug was contained in a revision to the helicopter maintenance manual. The actions specified in this AD are intended to detect an improperly torqued hub plug that could lead to tail rotor failure and subsequent loss of control of the helicopter.

Document Text

Show stored source text (verify against official source)
[Federal Register Volume 76, Number 166 (Friday, August 26, 2011)]
[Rules and Regulations]
[Pages 53312-53314]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2011-21475]


-----------------------------------------------------------------------

DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2011-0861; Directorate Identifier 2010-SW-092-AD; 
Amendment 39-16778; AD 2011-17-14]
RIN 2120-AA64


Airworthiness Directives; Agusta S.p.A. Model A109A and A109AII 
Helicopters

AGENCY: Federal Aviation Administration, DOT.

ACTION: Final rule; request for comments.

-----------------------------------------------------------------------

SUMMARY: This amendment adopts a new airworthiness directive (AD) for 
the specified Agusta S.p.A. (Agusta) helicopters with a certain tail 
rotor special hub plug (hub plug) installed. This action requires a 
one-time inspection to determine the tightening torque value of the hub 
plug, and depending on the inspection results, replacing certain parts 
or disassembling the tail rotor hub and blades assembly and inspecting 
for damage. If the tightening torque value is between 600 kgcm and 700 
kgcm, the lock washer and o-ring must be replaced with airworthy parts, 
and no further action is required. If the tightening torque value is 
greater than 700 kgcm, the hub plug must be replaced with an airworthy 
part. Torque the new hub plug to the specified tightening torque 
between 600 and 700 kgcm. If the tightening torque value of the hub 
plug is less than 600 kgcm, the tail rotor hub and blades assembly must 
be disassembled and inspected for damage. If a part is found that is 
outside allowable damage tolerances, that part must be replaced with an 
airworthy part. This amendment is prompted by the discovery that a 
wrong tightening torque value for the hub plug was contained in a 
revision to the helicopter maintenance manual. The actions specified in 
this AD are intended to detect an improperly torqued hub plug that 
could lead to tail rotor failure and subsequent loss of control of the 
helicopter.

DATES: Effective September 12, 2011.
    The incorporation by reference of certain publications listed in 
the regulations is approved by the Director of the Federal Register as 
of September 12, 2011.
    Comments for inclusion in the Rules Docket must be received on or 
before October 25, 2011.

ADDRESSES: Use one of the following addresses to submit comments on 
this AD:
    <bullet> Federal eRulemaking Portal: Go to <a href="http://www.regulations.gov">http://www.regulations.gov</a>. Follow the instructions for submitting comments.
    <bullet> Fax: (202) 493-2251.
    <bullet> Mail: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590.
    <bullet> Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New 
Jersey Avenue, SE., Washington, DC 20590, between 9 a.m. and 5 p.m., 
Monday through Friday, except Federal holidays.
    You may get the service information identified in this AD from 
Agusta Westland, Customer Support & Services, Via Per Tornavento 15, 
21019 Somma Lombardo (VA) Italy, ATTN: Giovanni Cecchelli; telephone 
39-0331-711133; fax 39 0331 711180; or at <a href="http://www.agustawestland.com/technical-bullettins">http://www.agustawestland.com/technical-bullettins</a>.
    Examining the Docket: You may examine the docket that contains the 
AD, any comments, and other information on the Internet at <a href="http://www.regulations.gov">http://www.regulations.gov</a>, or in person at the Docket Operations office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The Docket Operations office (telephone (800) 647-5527) is 
located in Room W12-140 on the ground floor of the West Building at the 
street address stated in the ADDRESSES section. Comments will be 
available in the AD docket shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Sharon Miles, Aerospace Engineer, FAA, 
Rotorcraft Directorate, Regulations and Policy Group, 2601 Meacham 
Blvd., Fort Worth, Texas 76137; telephone: (817) 222-5122; fax: (817) 
222-5961.

SUPPLEMENTARY INFORMATION: 

Discussion

    The European Aviation Safety Agency (EASA), which is the Technical 
Agent for the Member States of the European Union, has issued EASA 
Emergency AD No. 2010-0222-E, dated October 22, 2010 (EAD 2010-0222-E), 
to correct an unsafe condition for the specified Agusta model 
helicopters with a hub plug, part number (P/N) 109-0133-18-103, 
installed. EASA advises that a mistaken value of the tightening torque 
of the hub plug has been discovered in the maintenance manual of A109A 
and A109AII helicopters. The investigation carried out by Agusta has 
revealed that the wrong value of the tightening torque of the hub plug 
was introduced with Revision 9 of the A109A and A109AII Helicopter 
Maintenance Manual, dated June 15, 2009. EASA states that this 
condition could ultimately lead to a tail rotor malfunction. The 
actions specified in this AD are intended to detect an improperly 
torqued hub plug that could lead to tail rotor failure and subsequent 
loss of control of the helicopter.

Related Service Information

    Agusta has issued Mandatory Alert Bollettino Tecnico No. 109-132, 
dated October 22, 2010 (BT), which specifies performing a one-time 
inspection of the hub plug to verify the right tightening torque value, 
and provides instruction to restore the correct installation. If the

[[Page 53313]]

tightening torque value is at least 600 kgcm, the BT specifies removing 
the lock washer, P/N 109-0133-17-103, and the o-ring, P/N MS29561-119, 
and replacing each part with a new part. If the tightening torque value 
is lower than the minimum required 600 kgcm, the BT specifies 
instructions to inspect the tail rotor hub and blade assembly, P/N 109-
0131-02 (all dash numbers), for damage. If a damaged part is found that 
is outside the allowable damage tolerances, the BT specifies replacing 
the part with a new part. The BT also specifies restoring the 
tightening torque value of the hub plug to between 600 kgcm and 700 
kgcm. EASA classified this service bulletin as mandatory and issued EAD 
2010-0222-E to ensure the continued airworthiness of these helicopters.

FAA's Evaluation and Unsafe Condition Determination

    These helicopters have been approved by the aviation authority of 
Italy, and are approved for operation in the United States. Pursuant to 
our bilateral agreement with Italy, EASA, their technical 
representative, has notified us of the unsafe condition described in 
the EASA AD. We are issuing this AD because we evaluated all 
information provided by EASA and determined the unsafe condition exists 
and is likely to exist or develop on other helicopters of the same type 
design.

Differences Between This AD and the EASA AD

    This AD uses the term ``hours time-in-service'' to describe 
compliance times, and the EASA AD uses the term ``flight hours''. This 
AD specifies compliance with the requirements of this AD within 5 hours 
time-in-service (TIS) or 8 days, whichever occurs first. The EASA 
Emergency AD specifies compliance within 5 hours TIS, but no later than 
November 30, 2010, whichever occurs first. This AD addresses corrective 
action if the tightening torque of the hub plug is greater than the 
required value of 700 kgcm.

FAA's Determination and Requirements of This AD

    This unsafe condition is likely to exist or develop on other 
helicopters of the same type design. Therefore, this AD is being issued 
to detect an improperly torqued hub plug that could lead to tail rotor 
failure and subsequent loss of control of the helicopter. This AD 
requires within 5 hours TIS or 8 days, whichever comes first, the 
following:
    <bullet> Determine if the tightening torque value of the hub plug, 
P/N 109-0133-18-103, is between 600 kgcm and 700 kgcm.
    <bullet> If the tightening torque value of the hub plug is between 
600 and 700 kgcm, replace the lock washer, P/N 109-0133-17-103, and the 
o-ring, P/N MS29561-119, with an airworthy part.
    <bullet> If the tightening torque value of the hub plug is greater 
than 700 kgcm, replace the hub plug, P/N 109-0133-18-103 with an 
airworthy part. Torque the hub plug to the specified tightening torque 
between 600 and 700 kgcm.
    <bullet> If the tightening torque value of the hub plug is less 
than the required minimum 600 kgcm, remove the tail rotor hub and 
blades assembly, P/N 109-0131-02 (all dash numbers), and inspect the 
broaching and bearing faces of the trunnion, P/N 109-0131-05 or 109-
8131-33, for spalling, fretting, or wear. Inspect the hub plug, the 
spacers, P/N 109-0133-16-103 and 109-0130-89-1, and the static stop, P/
N 109-0130-27-5, for damage or corrosion. Inspect the broaching of the 
output drive shaft, P/N 109-0445-08-3 or 109-0445-08-7, for fretting or 
wear. If a part is found that is outside allowable damage tolerances, 
remove the unairworthy part and replace it with an airworthy part.
    Accomplish the actions by following specified portions of the 
service bulletin described previously. The short compliance time 
involved is required because the previously described critical unsafe 
condition can adversely affect the structural integrity and 
controllability of the helicopter. Therefore, the actions specified in 
this AD are required within 5 hours TIS or 8 days, whichever occurs 
first, a very short compliance time, and this AD must be issued 
immediately.
    Since a situation exists that requires the immediate adoption of 
this regulation, it is found that notice and opportunity for prior 
public comment hereon are impracticable, and that good cause exists for 
making this amendment effective in less than 30 days.

Costs of Compliance

    We estimate that this AD will affect about 63 helicopters of U.S. 
registry. We estimate the costs to accomplish the requirements of this 
AD as follows:

----------------------------------------------------------------------------------------------------------------
                                 Number of work
            Action                hours x labor     Labor      Parts      Cost per    Affected fleet     Fleet
                                      rate           cost       cost      aircraft         size           cost
----------------------------------------------------------------------------------------------------------------
Determine the tightening        0.25 hrs x labor        $21          0          $21  63..............     $1,323
 torque value of the hub plug    rate of $85.
 (one-time inspection).
Replace lock washer and O-ring  2.0 hrs x labor         170        287          457  56 (assume 89%       25,592
                                 rate of $85.                                         of fleet).
Replace hub plug..............  2.0 hrs x labor         170        850         1020  1 (assume 1% of        1020
                                 rate of $85.                                         the fleet.
Replace Trunnion, Hub Plug,     5.0 hrs. x labor        425      8,884        9,309  7 (assume 10% of     65,163
 Spacers, Static Stop.           rate of $85.                                         fleet).
                               ---------------------------------------------------------------------------------
    Total cost impact for this  ................  .........  .........  ...........  ................     93,098
     AD.
----------------------------------------------------------------------------------------------------------------

Comments Invited

    This AD is a final rule that involves requirements that affect 
flight safety and was not preceded by notice and an opportunity for 
public comment; however, we invite you to submit any written data, 
views, or arguments regarding this AD. Send your comments to an address 
listed under ADDRESSES. Include ``Docket No. FAA-2011-0861; Directorate 
Identifier 2010-SW-092-AD'' at the beginning of your comments. We 
specifically invite comments on the overall regulatory, economic, 
environmental, and energy aspects of the AD. We will consider all 
comments received by the closing date and may amend the AD in light of 
those comments.
    We will post all comments we receive, without change, to <a href="http://www.regulations.gov">http://www.regulations.gov</a>, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact 
with FAA personnel concerning this AD. Using the search function of the 
docket Web site, you can find and read the comments to any of our 
dockets, including the name

[[Page 53314]]

of the individual who sent the comment. You may review the DOT's 
complete Privacy Act Statement in the Federal Register published on 
April 11, 2000 (65 FR 19477-78).

Regulatory Findings

    We have determined that this AD will not have federalism 
implications under Executive Order 13132. This AD will not have a 
substantial direct effect on the States, on the relationship between 
the national Government and the States, or on the distribution of power 
and responsibilities among the various levels of government.
    For the reasons discussed above, I certify that the regulation:
    1. Is not a ``significant regulatory action'' under Executive Order 
12866;
    2. Is not a ``significant rule'' under the DOT Regulatory Policies 
and Procedures (44 FR 11034, February 26, 1979);
    3. Will not affect intrastate aviation in Alaska to the extent that 
it justifies making a regulatory distinction; and
    4. Will not have a significant economic impact, positive or 
negative, on a substantial number of small entities under the criteria 
of the Regulatory Flexibility Act.
    We prepared an economic evaluation of the estimated costs to comply 
with this AD. See the AD docket to examine the economic evaluation.

Authority for This Rulemaking

    Title 49 of the United States Code specifies the FAA's authority to 
issue rules on aviation safety. Subtitle I, Section 106, describes the 
authority of the FAA Administrator. Subtitle VII, Aviation Programs, 
describes in more detail the scope of the Agency's authority.
    We are issuing this rulemaking under the authority described in 
Subtitle VII, Part A, Subpart III, Section 44701, ``General 
requirements.'' Under that section, Congress charges the FAA with 
promoting safe flight of civil aircraft in air commerce by prescribing 
regulations for practices, methods, and procedures the Administrator 
finds necessary for safety in air commerce. This regulation is within 
the scope of that authority because it addresses an unsafe condition 
that is likely to exist or develop on products identified in this 
rulemaking action.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Incorporation by 
reference, Safety.

Adoption of the Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration amends Part 39 of 
the Federal Aviation Regulations (14 CFR Part 39) as follows:

PART 39--AIRWORTHINESS DIRECTIVES

0
1. The authority citation for Part 39 continues to read as follows:

    Authority:  49 U.S.C. 106(g), 40113, 44701.


Sec.  39.13  [Amended]

0
2. Section 39.13 is amended by adding a new airworthiness directive to 
read as follows:

2011-17-14 AGUSTA S.p.A.: Amendment 39-16678; Docket No. FAA-2011-
0861; Directorate Identifier 2010-SW-092-AD.

    Applicability: Models A109A and A109A II helicopters, with tail 
rotor special hub plug (hub plug), part number (P/N) 109-0133-18-
103; certificated in any category.
    Compliance: Required within 5 hours time-in-service (TIS) or 8 
days, whichever occurs first, unless accomplished previously.
    To detect an improperly torqued hub plug that could lead to tail 
rotor failure and subsequent loss of control of the helicopter, 
accomplish the following:
    (a) Determine if the tightening torque value of the hub plug is 
between 600 kgcm and 700 kgcm.
    (b) If the tightening torque value of the hub plug is between 
600 kgcm and 700 kgcm, remove and replace the lock washer, P/N 109-
0133-17-103, and the o-ring, P/N MS29561-119, with airworthy parts.
    (c) If the tightening torque value of the hub plug is greater 
than 700 kgcm, remove and replace the hub plug, P/N 109-0133-18-103 
with an airworthy part. Torque the hub plug to the specified 
tightening torque between 600 and 700 kgcm.
    (d) If the tightening torque value of the hub plug is less than 
the 600 kgcm, do the following:
    (1) Remove the tail rotor hub and blades assembly, P/N 109-0131-
02 (all dash numbers).
    (2) Inspect the broaching faces (splined area ``F'') and bearing 
faces (area ``D'') of the trunnion, P/N 109-0131-05 or 109-8131-33, 
for spalling, fretting, or wear by reference to Figure 2 of Agusta 
Mandatory Alert Bollettino Tecnico No. 109-132, dated October 22, 
2010 (BT). If there is spalling, fretting, or wear that is outside 
allowable damage tolerances specified in Figure 2 of the BT, replace 
the trunnion with an airworthy trunnion.
    (3) Inspect the hub plug, the spacers, P/N 109-0133-16-103 and 
109-0130-89-1, and the static stop, P/N 109-0130-27-5, for spalling, 
fretting, wear, or corrosion. If there is any spalling, fretting, 
wear, or corrosion, replace the part with an airworthy part.
    (4) Inspect the broaching area ``H'' of the output drive shaft, 
P/N 109-0445-08-3 or 109-0445-08-7, of the tail rotor gearbox 
assembly, P/N 109-0440-01, for fretting, wear, or other damage by 
referring to Figure 3 of the BT. If there is any fretting, wear, or 
other damage of 0.07 mm or more in depth between loaded and unloaded 
areas, replace the output drive shaft with an airworthy output drive 
shaft.
    (5) Reinstall the tail rotor hub and blade assembly, and tighten 
the torque on the hub plug to between 600 kgcm and 700 kgcm.
    (6) Accomplish a flap axis play inspection, a flap hinge 
friction inspection, and a tail rotor dynamic balance.
    (e) To request a different method of compliance or a different 
compliance time for this AD, follow the procedures in 14 CFR 39.19. 
Contact the Manager, Safety Management Group, ATTN: DOT/FAA 
Southwest Region, Sharon Miles, Rotorcraft Directorate, Regulations 
and Policy Group, ASW-111, 2601 Meacham Blvd., Fort Worth, Texas 
76137; telephone: (817) 222-5122; fax: (817) 222-5961, for 
information about previously approved alternative methods of 
compliance.
    (f) The Joint Aircraft System/Component (JASC) Code is 6500: 
Tail rotor drive system.
    (g) The inspection shall be done in accordance with the 
specified portions of Agusta Mandatory Alert Bollettino Tecnico No. 
109-132, dated October 22, 2010. The Director of the Federal 
Register approved this incorporation by reference in accordance with 
5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from 
Agusta Westland, Customer Support & Services, Via Per Tornavento 15, 
21019 Somma Lombardo (VA) Italy, ATTN: Giovanni Cecchelli; telephone 
39-0331-711133; fax 39 0331 711180; or at <a href="http://www.agustawestland.com/technical-bullettins">http://www.agustawestland.com/technical-bullettins</a>. Copies may be inspected 
at the FAA, Office of the Regional Counsel, Southwest Region, 2601 
Meacham Blvd., Room 663, Fort Worth, Texas, or at the National 
Archives and Records Administration (NARA). For information on the 
availability of this material at NARA, call 202-741-6030, or go to: 
<a href="http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html">http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html</a>.
    (h) This amendment becomes effective on September 12, 2011.

    Note: The subject of this AD is addressed in the European 
Aviation Safety Agency (Italy), Emergency AD 2010-0222-E, dated 
October 22, 2010.


    Issued in Fort Worth, Texas, on August 8, 2011.
Kim Smith,
Manager, Rotorcraft Directorate, Aircraft Certification Service.
[FR Doc. 2011-21475 Filed 8-25-11; 8:45 am]
BILLING CODE 4910-13-P

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