
[Federal Register: August 13, 2008 (Volume 73, Number 157)]
[Rules and Regulations]               
[Page 47032-47035]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr13au08-3]                         

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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. FAA-2008-0406; Directorate Identifier 2007-NM-196-AD; 
Amendment 39-15640; AD 2008-17-02]
RIN 2120-AA64

 
Airworthiness Directives; Airbus Model A310 Airplanes

AGENCY: Federal Aviation Administration (FAA), Department of 
Transportation (DOT).

ACTION: Final rule.

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SUMMARY: We are superseding an existing airworthiness directive (AD) 
for the products listed above. This 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:

    During routine visual inspection, a crack has been found in the 
wing MLG (main landing gear) rib 5 forward attachment lug on two 
A310 in-service aircraft. Laboratory examination of one of the 
cracked ribs confirmed that the crack is due to the presence of 
pitting corrosion in the forward lug holes. Also on both aircraft 
medium to heavy corrosion was found in the forward lugs on the 
opposite wing after removal of the bushes. This situation if not 
detected, could affect the structural integrity of the MLG 
attachment. * * *
* * * * *
    We are issuing this AD to require actions to correct the unsafe 
condition on these products.

DATES: This AD becomes effective September 17, 2008.
    The Director of the Federal Register approved the incorporation by 
reference of certain publications listed in this AD as of September 17, 
2008.
    The Director of the Federal Register previously approved the 
incorporation by reference of Airbus Service Bulletin A310-57A2088, 
excluding Appendix 01, dated November 6, 2006, listed in this AD, as of 
February 6, 2007 (72 FR 2612, January 22, 2007).

ADDRESSES: You may examine the AD docket on the Internet at http://
www.regulations.gov or in person at the U.S. Department of 
Transportation, Docket Operations, M-30, West Building Ground Floor, 
Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC.

FOR FURTHER INFORMATION CONTACT: Tom Stafford, Aerospace Engineer, 
International Branch, ANM-116, Transport Airplane Directorate, FAA, 
1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 
227-1622; fax (425) 227-1149.

SUPPLEMENTARY INFORMATION:

Discussion

    We issued a notice of proposed rulemaking (NPRM) to amend 14 CFR 
part 39 to include an AD that would apply to the specified products. 
That NPRM was published in the Federal Register on April 7, 2008 (73 FR 
18722). That NPRM proposed to correct an unsafe condition for the 
specified products. The MCAI states:

    During routine visual inspection, a crack has been found in the 
wing MLG (main landing gear) rib 5 forward attachment lug on two 
A310 in-service aircraft. Laboratory examination of one of the 
cracked ribs confirmed that the crack is due to the presence of 
pitting corrosion in the forward lug holes. Also on both aircraft 
medium to heavy corrosion was found in the forward lugs on the 
opposite wing after removal of the bushes. This situation if not 
detected, could affect the structural integrity of the MLG 
attachment. As an interim measure, Airbus published Alert Service 
Bulletin (ASB) A310-57A2088 to introduce a repetitive detailed 
visual inspection (DVI) of the forward attachment lug of MLG Rib 5. 
EASA issued Emergency Airworthiness Directive (EAD) 2006-0335-E 
[which corresponds to FAA AD 2007-02-09] to require the 
accomplishment of this repetitive DVI.
    In order to ensure the detection of any crack at an early stage 
in the forward lug of the RH (right-hand) and LH (left-hand) MLG Rib 
5 aft bearing attachment, the Type Certificate holder has developed 
a new inspection by means of ultrasonic method. For the reasons 
described above, this new inspection program is rendered mandatory 
by this AD, which cancels and replaces the requirement of EAD 2006-
0335-E.

    The corrective action includes repairing or replacing MLG Rib 5, as

[[Page 47033]]

applicable. You may obtain further information by examining the MCAI in 
the AD docket.

Comments

    We gave the public the opportunity to participate in developing 
this AD. We considered the comments received.

Clarification of Certain Requirements

    Airbus asks that we revise paragraph (g)(2) of the NPRM to clarify 
the intent of Airbus Service Bulletin A310-57-2090, Revision 01, dated 
December 19, 2007. Airbus states that paragraph (g)(2) of the NPRM 
refers to that service bulletin for replacement of the MLG Rib 5. 
However, Airbus clarifies that the intent of Service Bulletin A310-57-
2090 is not to provide instructions for the MLG Rib 5 replacement, but 
to introduce new bushes with increased interference fit into the aft 
bearing forward lug of MLG Rib 5. Airbus asks that paragraph (g)(2) of 
the NPRM be changed as follows, for clarification: ``Replacement of the 
MLG Rib 5 bushes with high interference fit in accordance with the 
instructions defined in Airbus Service Bulletin A310-57-2090. * * *''
    We agree that paragraph (g)(2) of this AD should be further 
clarified to address the commenter's suggestion; therefore, we have 
changed that paragraph accordingly.
    Airbus also asks that the last sentence of paragraphs (g)(3) and 
(g)(4)(ii) of the NPRM be changed to remove the reference to Airbus 
Service Bulletin A310-57-2090, Revision 01, dated December 19, 2007, 
when the MLG Rib 5 replacement is in question. Airbus asks that 
paragraphs (g)(3) and (g)(4)(ii) of the NPRM be changed as follows, for 
clarification: ``After MLG Rib 5 replacement, whether Airbus Service 
Bulletin A310-57-2090, Revision 01, dated December 19, 2007 is not 
accomplished: * * *''
    We agree that paragraphs (g)(3) and (g)(4)(ii) of this AD should be 
further clarified to capture the commenter's intent; therefore, we have 
changed those paragraphs accordingly.

Conclusion

    We reviewed the relevant data, considered the comments received, 
and determined that air safety and the public interest require adopting 
the AD with the changes described previously. We also determined that 
these changes will not increase the economic burden on any operator or 
increase the scope of the AD.

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 required different actions in this AD from those 
in the MCAI in order to follow our FAA policies. Any such differences 
are highlighted in a NOTE within the AD.

Costs of Compliance

    We estimate that this AD will affect 68 products of U.S. registry. 
We also estimate that it will take about 5 work-hours per product to 
comply with the basic requirements of this AD. The average labor rate 
is $80 per work-hour. Based on these figures, we estimate the cost of 
this AD to the U.S. operators to be $27,200, or $400 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 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 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 this AD:
    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 AD and placed it in the AD docket.

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 the NPRM, 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.

List of Subjects in 14 CFR Part 39

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

Adoption of the Amendment

0
Accordingly, under the authority delegated to me by the Administrator, 
the FAA amends 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. The FAA amends Sec.  39.13 by removing Amendment 39-14896 (72 FR 
2612, January 22, 2007) and adding the following new AD:

2008-17-02 Airbus: Amendment 39-15640. Docket No. FAA-2008-0406; 
Directorate Identifier 2007-NM-196-AD.

Effective Date

    (a) This airworthiness directive (AD) becomes effective 
September 17, 2008.

Affected ADs

    (b) The AD supersedes AD 2007-02-09, Amendment 39-14896.

Applicability

    (c) This AD applies to Airbus Model A310 airplanes, certificated 
in any category, all certified models, all serial numbers; except 
for those where LH (left-hand) and RH (right-hand) wing MLG (main 
landing gear) rib 5 forward lugs have been repaired by installation 
of oversized interference fit bushes as per Airbus A310 Repair 
Instruction

[[Page 47034]]

R572-49121, or which have had Airbus Service Bulletin A310-57-2090 
(Airbus modification 13329) embodied in service.

Subject

    (d) Air Transport Association (ATA) of America Code 57: Wings.

Reason

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

    During routine visual inspection, a crack has been found in the 
wing MLG (main landing gear) rib 5 forward attachment lug on two 
A310 in-service aircraft. Laboratory examination of one of the 
cracked ribs confirmed that the crack is due to the presence of 
pitting corrosion in the forward lug holes. Also on both aircraft 
medium to heavy corrosion was found in the forward lugs on the 
opposite wing after removal of the bushes. This situation if not 
detected, could affect the structural integrity of the MLG 
attachment. As an interim measure, Airbus published Alert Service 
Bulletin (ASB) A310-57A2088 to introduce a repetitive detailed 
visual inspection (DVI) of the forward attachment lug of MLG Rib 5. 
EASA issued Emergency Airworthiness Directive (EAD) 2006-0335-E 
[which corresponds to FAA AD 2007-02-09] to require the 
accomplishment of this repetitive DVI.
    In order to ensure the detection of any crack at an early stage 
in the forward lug of the RH (right-hand) and LH (left-hand) MLG Rib 
5 aft bearing attachment, the Type Certificate holder has developed 
a new inspection by means of ultrasonic method. For the reasons 
described above, this new inspection program is rendered mandatory 
by this AD, which cancels and replaces the requirement of EAD 2006-
0335-E.

The corrective action includes repairing or replacing MLG Rib 5, as 
applicable.

Restatement of Requirements of AD 2007-02-09

    (f) Unless already done, do the following actions specified in 
paragraphs (f)(1), (f)(2), and (f)(3) of this AD in accordance with 
the instructions defined in Airbus Service Bulletin A310-57A2088, 
dated November 6, 2006.
    (1) Before the accumulation of 12,000 total flight cycles, or 
within 14 days after February 6, 2007 (the effective date of AD 
2007-02-09), whichever occurs later: Perform a detailed visual 
inspection of the LH and RH wing MLG Rib 5 aft bearing forward lugs.
    (2) If any crack is detected at LH and/or RH aft bearing forward 
lug, contact Airbus and proceed with the replacement before next 
flight.
    (3) Repeat the inspection at intervals not exceeding 100 flight 
cycles.

New Requirements of This AD: Actions and Compliance

    (g) Unless already done, before the accumulation of 12,000 total 
flight cycles or before the accumulation of 12,000 flight cycles on 
MLG Rib 5, or within 14 days after the effective date of this AD, 
whichever occurs latest: Perform either a detailed visual inspection 
(DVI) or an ultrasonic inspection of the LH and RH MLG Rib 5 aft 
bearing forward lug for cracks, in accordance with the instructions 
defined in Airbus Service Bulletin A310-57-2091, excluding Appendix 
01, dated May 22, 2007. If a MLG Rib 5 has been replaced on one side 
only, then the RH and LH must be considered separately. Doing this 
inspection ends the requirements of paragraph (f) for that MLG Rib 5 
only.

    Note 1: The ultrasonic inspection will detect any crack at an 
early stage and will limit the risk of extensive repairs. This 
earlier crack detection is not possible with the DVI.

    (1) If no crack is detected during any inspection required by 
paragraph (g) of this AD: Repeat the applicable inspection at the 
time specified in paragraph (g)(1)(i) or (g)(1)(ii) of this AD.
    (i) Repeat the DVI thereafter at intervals not to exceed 100 
flight cycles.
    (ii) Repeat the ultrasonic inspection thereafter at intervals 
not to exceed 825 flight cycles.
    (2) Replacement of the MLG Rib 5 bushes with new bushes with 
high interference fit in the aft bearing forward lugs of MLG Rib 5, 
in accordance with the instructions defined in Airbus Service 
Bulletin A310-57-2090, Revision 01, dated December 19, 2007, ends 
the repetitive inspections required by paragraph (g)(1) of this AD 
for that MLG Rib 5 only.
    (3) If any crack is detected during the DVI required by 
paragraph (g) of this AD: Before further flight, contact Airbus for 
replacement instructions and replace the MLG Rib 5 bushes before 
further flight. Repeat the applicable inspection in paragraph (g) of 
this AD at the time specified in paragraph (g)(1)(i) or (g)(1)(ii) 
of this AD. Accomplishing the replacement of the MLG Rib 5 bushes 
with new bushes with high interference fit in the aft bearing 
forward lugs of MLG Rib 5, in accordance with the instructions 
defined in Airbus Service Bulletin A310-57-2090, Revision 01, dated 
December 19, 2007, ends the repetitive inspections required by 
paragraph (g)(1) of this AD for that MLG Rib 5 only.
    (4) If any crack is detected during the ultrasonic inspection 
required by paragraph (g) of this AD, before further flight, 
accomplish the actions specified in paragraph (g)(4)(i) or 
(g)(4)(ii) of this AD, as applicable.
    (i) If any crack is not visible on MLG Rib 5: Before further 
flight, repair MLG Rib 5 using Airbus A310 Repair Instruction R572-
49121, Issue C, dated May 2007. After embodiment of the repair 
instruction, no further actions are necessary as required by this AD 
and specified in Airbus Service Bulletin A310-57-2091, excluding 
Appendix 01, dated May 22, 2007, for that MLG Rib 5 only.
    (ii) If any crack is visible on MLG Rib 5: Before further 
flight, contact Airbus for rib replacement instructions, and replace 
before further flight. Repeat the applicable inspection in paragraph 
(g) of this AD at the time specified in paragraph (g)(1)(i) or 
(g)(1)(ii) of this AD. Accomplishing the replacement of the MLG Rib 
5 bushes with new bushes with high interference fit in the aft 
bearing forward lugs of MLG Rib 5, in accordance with the 
instructions defined in Airbus Service Bulletin A310-57-2090, 
Revision 01, dated December 19, 2007, ends the repetitive 
inspections required by paragraph (g) of this AD for that MLG Rib 5 
only.

FAA AD Differences

    Note 2: This AD differs from the MCAI and/or service information 
as follows:
    (1) Although the MCAI or service information allows flight with 
cracks on aft bearing forward lugs for a certain period of time, 
this AD requires replacing MLG Rib 5 before further flight if any 
crack is found.
    (2) Although the MCAI or service information specifies 
submitting an inspection report sheet to Airbus, this AD would not 
require that action.

Other FAA AD Provisions

    (h) The following provisions also apply to this AD:
    (1) Alternative Methods of Compliance (AMOCs): The Manager, 
International Branch, ANM-116, Transport Airplane Directorate, 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: Tom 
Stafford, Aerospace Engineer, International Branch, ANM-116, 
Transport Airplane Directorate, FAA, 1601 Lind Avenue, SW., Renton, 
Washington 98057-3356; telephone (425) 227-1622; fax (425) 227-1149. 
Before using any approved AMOC on any airplane to which the AMOC 
applies, notify your appropriate principal inspector (PI) in the FAA 
Flight Standards District Office (FSDO), or lacking a PI, your local 
FSDO.
    (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, the 
Office of Management and Budget (OMB) has approved the information 
collection requirements and has assigned OMB Control Number 2120-
0056.

Related Information

    (i) Refer to MCAI European Aviation Safety Agency Airworthiness 
Directive 2007-0195, dated July 19, 2007; and Airbus Service 
Bulletins A310-57-2090, Revision 01, dated December 19, 2007; and 
A310-57-2091, including Appendix 01, dated May 22, 2007; for related 
information.

Material Incorporated by Reference

    (j) You must use the applicable service information specified in 
Table 1 of this AD to do the actions required by this AD, unless the 
AD specifies otherwise.

[[Page 47035]]



                                 Table 1--All Material Incorporated by Reference
----------------------------------------------------------------------------------------------------------------
      Airbus service information                Revision/issue level                         Date
----------------------------------------------------------------------------------------------------------------
Service Bulletin A310-57A2088,         Original.............................  November 6, 2006.
 excluding Appendix 01.
Service Bulletin A310-57-2090........  01...................................  December 19, 2007.
Service Bulletin A310-57-2091,         Original.............................  May 22, 2007.
 excluding Appendix 01.
A310 Repair Instruction R572-49121...  C....................................  May 2007.
----------------------------------------------------------------------------------------------------------------

    (1) The Director of the Federal Register approved the 
incorporation by reference of the service information specified in 
Table 2 of this AD under 5 U.S.C. 552(a) and 1 CFR part 51.

                                 Table 2--New Material Incorporated by Reference
----------------------------------------------------------------------------------------------------------------
      Airbus service information                Revision/issue level                         Date
----------------------------------------------------------------------------------------------------------------
Service Bulletin A310-57-2090........  01...................................  December 19, 2007.
Service Bulletin A310-57-2091,         Original.............................  May 22, 2007.
 excluding Appendix 01.
A310 Repair Instruction R572-49121...  C....................................  May 2007.
----------------------------------------------------------------------------------------------------------------

    (2) The Director of the Federal Register previously approved the 
incorporation by reference of Airbus Service Bulletin A310-57A2088, 
excluding Appendix 01, dated November 6, 2006, on February 6, 2007 
(72 FR 2612, January 22, 2007).
    (3) For service information identified in this AD, contact 
Airbus, 1 Rond Point Maurice Bellonte, 31707 Blagnac Cedex, France.
    (4) You may review copies at the FAA, Transport Airplane 
Directorate, 1601 Lind Avenue, SW., Renton, Washington; 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: http://www.archives.gov/federal-register/cfr/ibr-
locations.html.

    Issued in Renton, Washington, on July 31, 2008.
Ali Bahrami,
Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. E8-18561 Filed 8-12-08; 8:45 am]

BILLING CODE 4910-13-P
