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[Federal Register: August 23, 2010 (Volume 75, Number 162)]
[Proposed Rules]               
[Page 51698-51701]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr23au10-21]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2010-0803; Directorate Identifier 2010-NM-124-AD]
RIN 2120-AA64

 
Airworthiness Directives; Airbus Model A310 Series Airplanes; and 
Model A300 B4-600, A300 B4-600R, A300 F4-600R Series Airplanes, and 
Model A300 C4-605R Variant F Airplanes (Collectively Called A300-600 
Series Airplanes)

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: We propose to adopt a new airworthiness directive (AD) for the 
products listed above. This proposed AD results from mandatory 
continuing airworthiness information (MCAI) originated by an aviation 
authority of another country to identify and correct an unsafe 
condition on an aviation product. The MCAI describes the unsafe 
condition as: The ball screw nut assemblies of the first 70 Trimmable 
Horizontal Stabilizer Actuators (THSA) manufactured by Goodrich were 
fitted with an upper attachment gimbal having a thickness of 58 mm 
(2.28 in), which is different from the design of the final production 
standard. The gimbal installed on the subsequent THSAs (final 
production standard) is more robust, having a thickness of 70mm (2.76 
in). During the fatigue life demonstration of the THSA upper attachment 
primary load path elements, only a gimbal having a thickness of 70mm 
(2.76 in) was used. Thereafter, no additional justification work to 
demonstrate the robustness of the upper attachment fitted with a gimbal 
of 58 mm was accomplished. In case of failure of this gimbal, the THSA 
upper attachment primary load path would be lost and the THSA upper 
attachment secondary load path would engage. Because the upper 
attachment secondary load path will only withstand the loads for a 
limited period of time, the condition where it would be engaged and not 
detected could lead to failure of the secondary load path, which would 
likely result in loss of control of the aeroplane. The proposed AD 
would require actions that are intended to address the unsafe condition 
described in the MCAI.

DATES: We must receive comments on this proposed AD by October 7, 2010.

[[Page 51699]]

ADDRESSES: You may send comments by any of the following methods:
     Federal eRulemaking Portal: Go to http://www.regulations.gov. Follow the instructions for submitting comments.
     Fax: (202) 493-2251.
     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.
     Hand Delivery: U.S. Department of Transportation, Docket 
Operations, M-30, West Building Ground Floor, Room W12-40, 1200 New 
Jersey Avenue, SE., Washington, DC, between 9 a.m. and 5 p.m., Monday 
through Friday, except Federal holidays.
    For service information identified in this proposed AD, contact 
Airbus SAS--EAW (Airworthiness Office), 1 Rond Point Maurice Bellonte, 
31707 Blagnac Cedex, France; telephone +33 5 61 93 36 96; fax +33 5 61 
93 44 51; e-mail: account.airworth-eas@airbus.com; Internet http://www.airbus.com. You may review copies of the referenced service 
information at the FAA, Transport Airplane Directorate, 1601 Lind 
Avenue, SW., Renton, Washington. For information on the availability of 
this material at the FAA, call 425-227-1221.

Examining the AD Docket

    You may examine the AD docket on the Internet at http://www.regulations.gov; or in person at the Docket Operations office 
between 9 a.m. and 5 p.m., Monday through Friday, except Federal 
holidays. The AD docket contains this proposed AD, the regulatory 
evaluation, any comments received, and other information. The street 
address for the Docket Operations office (telephone (800) 647-5527) is 
in the ADDRESSES section. Comments will be available in the AD docket 
shortly after receipt.

FOR FURTHER INFORMATION CONTACT: Dan Rodina, Aerospace Engineer, 
International Branch, ANM-116, Transport Airplane Directorate, FAA, 
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 
227-2125; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION:

Comments Invited

    We invite you to send any written relevant data, views, or 
arguments about this proposed AD. Send your comments to an address 
listed under the ADDRESSES section. Include ``Docket No. FAA-2010-0803; 
Directorate Identifier 2010-NM-124-AD'' at the beginning of your 
comments. We specifically invite comments on the overall regulatory, 
economic, environmental, and energy aspects of this proposed AD. We 
will consider all comments received by the closing date and may amend 
this proposed AD based on those comments.
    We will post all comments we receive, without change, to http://www.regulations.gov, including any personal information you provide. We 
will also post a report summarizing each substantive verbal contact we 
receive about this proposed AD.

Discussion

    The European Aviation Safety Agency (EASA), which is the Technical 
Agent for the Member States of the European Community, has issued EASA 
Airworthiness Directive 2010-0092, dated May 21, 2010 (referred to 
after this as ``the MCAI''), to correct an unsafe condition for the 
specified products. The MCAI states:

    The ball screw nut assemblies of the first 70 Trimmable 
Horizontal Stabilizer Actuators (THSA) manufactured by Goodrich were 
fitted with an upper attachment gimbal having a thickness of 58 mm 
(2.28 in), which is different from the design of the final 
production standard. The gimbal installed on the subsequent THSAs 
(final production standard) is more robust, having a thickness of 70 
mm (2.76 in).
    During the fatigue life demonstration of the THSA upper 
attachment primary load path elements, only a gimbal having a 
thickness of 70mm (2.76 in) was used. Thereafter, no additional 
justification work to demonstrate the robustness of the upper 
attachment fitted with a gimbal of 58 mm was accomplished.
    In case of failure of this gimbal, the THSA upper attachment 
primary load path would be lost and the THSA upper attachment 
secondary load path would engage.
    Because the upper attachment secondary load path will only 
withstand the loads for a limited period of time, the condition 
where it would be engaged and not detected could lead to failure of 
the secondary load path, which would likely result in loss of 
control of the aeroplane.
    As the affected ball screw nut assemblies (including the gimbal) 
could have been moved from one THSA to another during maintenance 
operation and because the change from the old design to the final 
production standard design is not identified through a dedicated 
THSA Part Number, a gimbal with thickness of 58 mm (2.28 in) can be 
fitted on any A310 or A300-600 aeroplane.
    For the reasons described above, this AD requires the 
identification of the THSA which have a 58 mm (2.28 in) gimbal 
installed, repetitive [general visual] inspections to check whether 
there is engagement of the secondary load path and, depending on 
findings, associated corrective action(s).

Corrective actions include contacting Airbus for repair instructions 
and doing the repair. You may obtain further information by examining 
the MCAI in the AD docket.

Relevant Service Information

    Airbus has issued Mandatory Service Bulletins A300-27A6067, 
Revision 01, including Appendix 01, dated May 12, 2010; and A310-
27A2104, Revision 01, including Appendix 01, dated May 12, 2010. The 
actions described in this service information are intended to correct 
the unsafe condition identified in the MCAI.

FAA's Determination and Requirements of This Proposed AD

    This product has been approved by the aviation authority of another 
country, and is approved for operation in the United States. Pursuant 
to our bilateral agreement with the State of Design Authority, we have 
been notified of the unsafe condition described in the MCAI and service 
information referenced above. We are proposing this AD because we 
evaluated all pertinent information and determined an unsafe condition 
exists and is likely to exist or develop on other products of the same 
type design.

Differences Between This AD and the MCAI or Service Information

    We have reviewed the MCAI and related service information and, in 
general, agree with their substance. But we might have found it 
necessary to use different words from those in the MCAI to ensure the 
AD is clear for U.S. operators and is enforceable. In making these 
changes, we do not intend to differ substantively from the information 
provided in the MCAI and related service information.
    We might also have proposed different actions in this AD from those 
in the MCAI in order to follow FAA policies. Any such differences are 
highlighted in a Note within the proposed AD.

Costs of Compliance

    Based on the service information, we estimate that this proposed AD 
would affect about 170 products of U.S. registry. We also estimate that 
it would take about 2 work-hours per product to comply with the basic 
requirements of this proposed AD. The average labor rate is $85 per 
work-hour. Based on these figures, we estimate the cost of the proposed 
AD on U.S. operators to be $28,900, or $170 per product.

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

[[Page 51700]]

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.

Regulatory Findings

    We determined that this proposed AD would not have federalism 
implications under Executive Order 13132. This proposed AD would 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 this proposed 
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); and
    3. 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 a regulatory evaluation of the estimated costs to 
comply with this proposed AD and placed it in the AD docket.

List of Subjects in 14 CFR Part 39

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

The Proposed Amendment

    Accordingly, under the authority delegated to me by the 
Administrator, the FAA proposes to amend 14 CFR part 39 as follows:

PART 39--AIRWORTHINESS DIRECTIVES

    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]

    2. The FAA amends Sec.  39.13 by adding the following new AD:

Airbus: Docket No. FAA-2010-0803; Directorate Identifier 2010-NM-
124-AD.

Comments Due Date

    (a) We must receive comments by October 7, 2010.

Affected ADs

    (b) None.

Applicability

    (c) This AD applies to Airbus Model A300 B4-601, B4-603, B4-620, 
B4-622, B4-605R, B4-622R, F4-605R, and F4-622R airplanes; Model A300 
C4-605R Variant F airplanes; and Model A310-203, -204, -221, -222, -
304, -322, -324, and -325 airplanes; certificated in any category, 
all certified models, all manufacturer serial numbers.

Subject

    (d) Air Transport Association (ATA) of America Code 27: Flight 
controls.

Reason

    (e) The mandatory continuing airworthiness information (MCAI) 
states:

    The ball screw nut assemblies of the first 70 Trimmable 
Horizontal Stabilizer Actuators (THSA) manufactured by Goodrich were 
fitted with an upper attachment gimbal having a thickness of 58 mm 
(2.28 in), which is different from the design of the final 
production standard. The gimbal installed on the subsequent THSAs 
(final production standard) is more robust, having a thickness of 
70mm (2.76 in).
    During the fatigue life demonstration of the THSA upper 
attachment primary load path elements, only a gimbal having a 
thickness of 70mm (2.76 in) was used. Thereafter, no additional 
justification work to demonstrate the robustness of the upper 
attachment fitted with a gimbal of 58 mm was accomplished.
    In case of failure of this gimbal, the THSA upper attachment 
primary load path would be lost and the THSA upper attachment 
secondary load path would engage.
    Because the upper attachment secondary load path will only 
withstand the loads for a limited period of time, the condition 
where it would be engaged and not detected could lead to failure of 
the secondary load path, which would likely result in loss of 
control of the aeroplane.

Compliance

    (f) You are responsible for having the actions required by this 
AD performed within the compliance times specified, unless the 
actions have already been done.

Actions

    (g) Within 130 flight cycles or 650 flight hours after the 
effective date of this AD, whichever occurs first, measure the 
thickness of the trimmable horizontal stabilizer actuators (THSA) 
upper attachment gimbal, in accordance with the Accomplishment 
Instructions of Airbus Mandatory Service Bulletin A300-27A6067, 
Revision 01, dated May 12, 2010 (for Model A300-600 series 
airplanes); or A310-27A2104, Revision 01, dated May 12, 2010 (for 
Model A310 series airplanes).
    (1) If, during the measurement required by paragraph (g) of this 
AD, the gimbal thickness is 58 mm (2.28 in.)  5 mm (0.20 
in.), before further flight, do a general visual inspection of the 
THSA upper attachment to determine if the THSA upper attachment 
secondary load path is engaged, in accordance with the 
Accomplishment Instructions of Airbus Mandatory Service Bulletin 
A300-27A6067, Revision 01, dated May 12, 2010 (for Model A300-600 
series airplanes); or A310-27A2104, Revision 01, dated May 12, 2010 
(for Model A310 series airplanes). Repeat the inspection thereafter 
at intervals not to exceed 130 flight cycles or 650 flight hours, 
whichever occurs first, in accordance with the Accomplishment 
Instructions of Airbus Mandatory Service Bulletin A300-27A6067, 
Revision 01, dated May 12, 2010 (for Model A300-600 series 
airplanes); or A310-27A2104, Revision 01, dated May 12, 2010 (for 
Model A310 series airplanes).
    (2) If, during the measurement required by paragraph (g) of this 
AD, the gimbal thickness is not 58 mm (2.28 in.)  5 mm 
(0.20 in.), except for the requirements of paragraph (k) of this AD, 
no further action is required of this AD.
    (h) If, during any inspection required by paragraph (g)(1) of 
this AD, the THSA upper attachment secondary load path is found to 
be engaged, before further flight, contact Airbus for repair 
instructions and do the repair.

Actions Accomplished According to Previous Issue of Service Bulletin

    (i) Actions accomplished before the effective date of this AD in 
accordance with Airbus Mandatory Service Bulletin A300-27A6067 (for 
Model A300-600 series airplanes) or A310-27A2104 (for Model A310 
series airplanes), both dated May 6, 2010, are considered acceptable 
for compliance with the corresponding action specified in this AD.

Reporting Requirement

    (j) Submit a report of the findings (both positive and negative) 
of the measurement required by paragraph (g) of this AD to Airbus, 
as identified in Appendix 01 of Airbus Mandatory Service Bulletin 
A300-27A6067, Revision 01, dated May 12, 2010 (for Model A300-600 
series airplanes); or A310-27A2104, Revision 01, dated May 12, 2010 
(for Model A310 series airplanes); at the applicable time specified 
in paragraph (l)(1) or (l)(2) of this AD. The report must include 
the information specified in Appendix 01 of Airbus Mandatory Service 
Bulletin A300-27A6067, Revision 01, dated May 12, 2010 (for Model 
A300-600 series airplanes); or A310-27A2104, Revision 01, dated May 
12, 2010 (for Model A310 series airplanes).
    (1) If the measurement was done on or after the effective date 
of this AD: Submit the report within 30 days after the inspection.
    (2) If the measurement was done before the effective date of 
this AD: Submit the report within 30 days after the effective date 
of this AD.

Parts Installation

    (k) As of the effective date of this AD, no person may install, 
on any airplane, a THSA, unless it is in compliance with the 
requirements of this AD.

[[Page 51701]]

FAA AD Differences

    Note 1:  This AD differs from the MCAI and/or service 
information as follows: The MCAI does not include a reporting 
requirement; however, the service bulletin recommends reporting. 
Paragraph (j) of this AD specifies a reporting requirement.

Other FAA AD Provisions

    (l) The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, 
International Branch, ANM-116, FAA, has the authority to approve 
AMOCs for this AD, if requested using the procedures found in 14 CFR 
39.19. Send information to ATTN: Dan Rodina, Aerospace Engineer, 
International Branch, ANM-116, Transport Airplane Directorate, FAA, 
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone 
(425) 227-2125; fax (425) 227-1149. Before using any approved AMOC 
on any airplane to which the AMOC applies, notify your principal 
maintenance inspector (PMI) or principal avionics inspector (PAI), 
as appropriate, or lacking a principal inspector, your local Flight 
Standards District Office. The AMOC approval letter must 
specifically reference this AD.
    (2) Airworthy Product: For any requirement in this AD to obtain 
corrective actions from a manufacturer or other source, use these 
actions if they are FAA-approved. Corrective actions are considered 
FAA-approved if they are approved by the State of Design Authority 
(or their delegated agent). You are required to assure the product 
is airworthy before it is returned to service.
    (3) Reporting Requirements: For any reporting requirement in 
this AD, under the provisions of the Paperwork Reduction Act (44 
U.S.C. 3501 et seq.), the Office of Management and Budget (OMB) has 
approved the information collection requirements and has assigned 
OMB Control Number 2120-0056.

Related Information

    (m) Refer to MCAI EASA Airworthiness Directive 2010-0092, dated 
May 21, 2010; Airbus Mandatory Service Bulletin A300-27A6067, 
Revision 01, dated May 12, 2010; and Airbus Mandatory Service 
Bulletin A310-27A2104, Revision 01, dated May 12, 2010; for related 
information.

    Issued in Renton, Washington, on August 16, 2010.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 2010-20854 Filed 8-20-10; 8:45 am]
BILLING CODE 4910-13-P
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