AD 2010-23-15

We are adopting a new airworthiness directive (AD) for certain Model 777-200, -200LR, -300, and -300ER series airplanes. This AD requires removing and repairing the sealant at the four lower corners of the wing center section and the four lower t-chord segment gaps on each side of the wing center section. This AD results from reports of fuel leakage from the center tank. We are issuing this AD to detect and correct improperly applied sealant, which could result in the disbonding and displacing of sealant, and consequent fuel leaks. On the ground, uncontained fuel leakage could result in pooling, and pooling combined with an ignition source could result in a fire.

Final rule.

2010-23-15 The Boeing Company: Amendment 39-16504. Docket No. FAA- 2010-0376; Directorate Identifier 2009-NM-267-AD. \n\nEffective Date \n\n\t(a) This airworthiness directive (AD) is effective December 22, 2010. \n\nAffected ADs \n\n\t(b) None. \n\nApplicability \n\n\t(c) This AD applies to The Boeing Company Model 777-200, -200LR, -300, and -300ER series airplanes, certificated in any category; as identified in Boeing Special Attention Service Bulletin 777-57-0063, Revision 1, dated May 14, 2009. \n\nSubject \n\n\t(d) Air Transport Association (ATA) of America Code 57: Wings. \n\nUnsafe Condition \n\n\t(e) This AD results from reports of fuel leakage from the center tank. We are issuing this AD to detect and correct improperly applied sealant, which could result in the disbonding and displacing of sealant, and consequent fuel leaks. On the ground, uncontained fuel leakage could result in pooling, and pooling combined with an ignition source could result in a fire. \n\nCompliance \n\n\t(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. \n\nRemoval and Repair of Sealant \n\n\t(g) Within 36 months or 6,000 flight cycles after the effective date of this AD, whichever occurs first: Remove and repair the sealant at the four lower corners of the wing center section and the four lower t-chord segment gaps on each side of the wing center section, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-57-0063, Revision 1, dated May 14, 2009. \n\nCredit for Actions Accomplished According to Previous Issue of Service Bulletin \n\n\t(h) Actions accomplished before the effective date of this AD in accordance with Boeing Special Attention Service Bulletin 777-57- 0063, dated November 20, 2008, are considered acceptable for compliance with the corresponding action specified in this AD. \n\nAlternative Methods of Compliance (AMOCs)(i)(1) The Manager, Seattle Aircraft Certification Office (ACO), 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: Kevin Nguyen, Aerospace Engineer, Propulsion Branch, ANM-140S, FAA, Seattle Aircraft Certification Office (ACO), 1601 Lind Avenue, SW., Renton, Washington 98057-3356; telephone (425) 917-6501; fax (425) 917-6590. Information may be e-mailed to: 9-ANM-Seattle-ACO- AMOC-Requests@faa.gov. \n\n\t(2) To request a different method of compliance or a different compliance time for this AD, follow the procedures in 14 CFR 39.19. 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. \n\nMaterial Incorporated by Reference \n\n\t(j) You mustuse Boeing Special Attention Service Bulletin 777- 57-0063, Revision 1, dated May 14, 2009, to do the actions required by this AD, unless the AD specifies otherwise. \n\n\t(1) The Director of the Federal Register approved the incorporation by reference of this service information under 5 U.S.C. 552(a) and 1 CFR part 51. \n\n\t(2) For service information identified in this AD, contact Boeing Commercial Airplanes, Attention: Data & Services Management, P.O. Box 3707, MC 2H-65, Seattle, Washington 98124-2207; telephone 206-544-5000, extension 1; fax 206-766-5680; e-mail me.boecom@boeing.com; Internet https://www.myboeingfleet.com. \n\n\t(3) You may review copies of the 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. \n\n\t(4) You may also review copies of the service information that is incorporated by reference 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/code_of_federal_regulations/ ibr_locations.html.

Discussion \n\n\tWe issued a notice of proposed rulemaking (NPRM) to amend 14 CFR part 39 to include an airworthiness directive (AD) that would apply to certain Model 777-200, -200LR, -300, and -300ER series airplanes. That NPRM was published in the Federal Register on April 8, 2010 (75 FR 17889). That NPRM proposed to require removing and repairing the sealant at the four lower corners of the wing center section and the four lower t-chord segment gaps on each side of the wing center section. \n\nComments \n\n\tWe gave the public the opportunity to participate in developing this AD. We considered the comments received from the two commenters. \n\nSupport for the NPRM \n\n\tContinental Airlines (CAL) stated that it concurs with intent of the NRPM to ensure a high level of safety for the Model 777 airplane fleet. \n\nRequest to Include Revised Inspection Criteria in Revised Service Information \n\n\tBoeing requested that we revise the NPRM to refer to Revision2 of Boeing Special Attention Service Bulletin 777-57-0063. Boeing stated that this revision includes an alternative inspection, and, depending on the inspection findings, it may be unnecessary to remove and replace the sealant. Furthermore, Boeing requested that we provide credit for actions accomplished in accordance with Boeing Special Attention Service Bulletin 777-57-0063, Revision 1, dated May 14, 2009. \n\n\tCAL also requested a provision to allow the inspection of the sealant condition in the affected areas before the sealant repair that is specified by Boeing Special Attention Service Bulletin 777-57-0063, Revision 1, dated May 14, 2009. CAL stated it believes that the additional inspection of the sealant is required to prevent unnecessary corrective actions on the affected airplanes that do not have the fuel leakage problems. CAL based its recommendation on its two affected airplanes that have not had any abnormal fuel leakage. CAL stated that Boeing has agreed that such a provision is acceptable to ensure an adequate level of safety. CAL asked that we revise the proposed AD to include the additional inspection criteria. \n\n\tWe infer that Boeing is asking us to revise the NPRM to add an additional inspection for sealant that Boeing plans to include in the next revision of the service information. We agree that an alternative inspection may prevent unnecessarily removing the sealant. However, we do not agree to delay this AD action until after Boeing revises the service bulletin, since sufficient methods specified in Boeing Special Attention Service Bulletin 777-57-0063, Revision 1, dated May 14, 2009, address the unsafe condition within the compliance time. However, after reviewing the next revision of this service bulletin, we might consider approving it as an alternative method of compliance (AMOC), if requested. In addition, any operator may request approval of an AMOC under the provisions of paragraph (i) of the final rule if data are submitted to substantiate that such a request would provide an acceptable level of safety. We have not changed this final rule in regard to this issue. \n\nConclusion \n\n\tWe reviewed the relevant data, considered the comments received, and determined that air safety and the public interest require adopting the AD as proposed. \n\nCosts of Compliance \n\n\tWe estimate that this AD affects 8 airplanes of U.S. registry. We also estimate that it will take about 10 work-hours per product to comply with this AD. The average labor rate is $85 per work-hour. Based on these figures, we estimate the cost of this AD to the U.S. operators to be $6,800, or $850 per product. \n\nAuthority for This Rulemaking \n\n\tTitle 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. \n\n\tWe are issuing this rulemakingunder 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. \n\nRegulatory Findings \n\n\tThis 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. \n\n\tFor the reasons discussed above, I certify that this AD: \n\n\t(1) Is not a "significant regulatory action'' under Executive Order 12866,(2) Is not a "significant rule'' under DOT Regulatory Policies and Procedures (44 FR 11034, February 26, 1979), and \n\n\t(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. \n\n\tYou can find our regulatory evaluation and the estimated costs of compliance in the AD Docket. \n\nList of Subjects in 14 CFR Part 39 \n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference, Safety. \n\nAdoption of the Amendment \n\nAccordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows: \n\nPART 39--AIRWORTHINESS DIRECTIVES \n\n1. The authority citation for part 39 continues to read as follows: \n\n\tAuthority: 49 U.S.C. 106(g), 40113, 44701. \n\nSec. 39.13 (Amended) \n\n2. The FAA amends Sec. 39.13 by adding the following new AD: