AD 2012-12-08

We are adopting a new airworthiness directive (AD) for certain The Boeing Company Model 777-200 and -300 series airplanes. This AD was prompted by reports of cracked retract actuator fuse pins that can fail earlier than the previously determined safe life limit of the pins. A fractured retract actuator fuse pin can cause the main landing gear to extend without restriction and attempt to lock into position under high dynamic loads. This AD requires an inspection for the part number of the fuse pin, and replacement of the pin if necessary. We are issuing this AD to prevent structural damage to the side and drag brace lock assemblies, which could result in landing gear collapse during touchdown, rollout, or taxi.

Final rule.

Adoption of the Amendment \n\n\n\tAccordingly, under the authority delegated to me by the Administrator, the FAA amends 14 CFR part 39 as follows: \n\nPART 39--AIRWORTHINESS DIRECTIVES \n\n0 1. The authority citation for part 39 continues to read as follows: \n\n\n\tAuthority: 49 U.S.C. 106(g), 40113, 44701. \n\n\n\nSec. 39.13 (Corrected)\n\n0 2. The FAA amends Sec. 39.13 by adding the following new airworthiness directive (AD): \n\n2012-12-08 The Boeing Company: Amendment 39-17088; Docket No. FAA- 2011-1412; Directorate Identifier 2011-NM-158-AD. \n\n(a) Effective Date \n\n\n\tThis AD is effective July 30, 2012. \n\n(b) Affected ADs \n\n\n\tNone. \n\n(c) Applicability \n\n\n\tThis AD applies to The Boeing Company Model 777-200 and -300 series airplanes; certificated in any category; as identified in Boeing Special Attention Service Bulletin 777-32-0083, Revision 1, dated February 17, 2011. \n\n(d) Subject \n\n\n\tJoint Aircraft System Component (JASC)/Air Transport Association (ATA) ofAmerica Code 32: Main landing gear. \n\n(e) Unsafe Condition \n\n\n\tThis AD was prompted by reports of cracked retract actuator fuse pins that can fail earlier than the previously determined safe life limit of the pins. A fractured retract actuator fuse pin can cause the main landing gear (MLG) to extend without restriction and attempt to lock into position under high dynamic loads. We are issuing this AD to prevent structural damage to the side and drag brace lock assemblies, which could result in landing gear collapse during touchdown, rollout, or taxi. \n\n(f) Compliance \n\n\n\tComply with this AD within the compliance times specified, unless already done. \n\n(g) Inspection of Retract Actuator Fuse Pin \n\n\n\tWithin 18 months after the effective date of this AD: Inspect the part number of the fuse pins of the left and right MLG retract actuators, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-32-0083, Revision 1, dated February 17, 2011. A review of airplane maintenance records is acceptable in lieu of this inspection if the part number of the installed actuator fuse pin can be conclusively determined from that review. \n\t(1) If any retract actuator fuse pin having part number 112W1769-3 is found installed, no further action is required by this paragraph for that fuse pin. \n\t(2) If any retract actuator fuse pin having part number 112W1769-1 is found installed and the pin has accumulated more than 10,000 total flight cycles as of the effective date of this AD: Within 18 months after the effective date of this AD, replace the fuse pin with a new part number 112W1769-3 fuse pin, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-32-0083, Revision 1, dated February 17, 2011. \n\t(3) If any retract actuator fuse pin having part number 112W1769-1 is found installed and the pin has accumulated 8,000 or more total flight cycles, but fewer than or equal to 10,000 total flight cycles, as of the effective date of this AD: Before the accumulation of 10,000 total flight cycles on the pin, or within 18 months after the effective date of this AD, whichever occurs later, replace the fuse pin with a new part number 112W1769-3 fuse pin, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-32-0083, Revision 1, dated February 17, 2011. \n\t(4) If any retract actuator fuse pin having part number 112W1769-1 is found installed and the pin has accumulated fewer than 8,000 total flight cycles as of the effective date of this AD: Before the accumulation of 8,000 total flight cycles on the pin, or within 24 months after the effective date of this AD, whichever occurs later, replace the fuse pin with a new part number 112W1769-3 fuse pin, in accordance with the Accomplishment Instructions of Boeing Special Attention Service Bulletin 777-32-0083, Revision 1, dated February 17, 2011. \n\n(h) Parts Installation \n\n\n\tAs of theeffective date of this AD, no person may install a retract actuator fuse pin having part number 112W1769-1 on any airplane. \n\n(i) Credit for Previous Actions \n\n\n\tThis paragraph provides credit for actions required by paragraph (g) of this AD, if those actions were performed before the effective date of this AD using Boeing Special Attention Service Bulletin 777- 32-0083, dated February 5, 2009. \n\n(j) Alternative Methods of Compliance (AMOCs) \n\n\n\t(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. In accordance with 14 CFR 39.19, send your request to your principal inspector or local Flight Standards District Office, as appropriate. If sending information directly to the manager of the ACO, send it to the attention of the person identified in the Related Information section of this AD. Information may be emailed to: 9-ANM-Seattle-ACO-AMOC-Requests@faa.gov.(2) Before using any approved AMOC, notify your appropriate principal inspector, or lacking a principal inspector, the manager of the local flight standards district office/certificate holding district office. \n\t(3) An AMOC that provides an acceptable level of safety may be used for any repair required by this AD if it is approved by Boeing Commercial Airplanes Organization Designation Authorization (ODA) that has been authorized by the Manager, Seattle ACO, to make those findings. For a repair method to be approved, the repair must meet the certification basis of the airplane, and the approval must specifically refer to this AD. \n\n(k) Related Information \n\n\n\tFor more information about this AD, contact James Sutherland, Aerospace Engineer, Airframe Branch, ANM-120S, FAA, Seattle Aircraft Certification Office, 1601 Lind Avenue SW., Renton, WA 98057-3356; phone: 425-917-6533; fax: 425-917-6590; email: james.sutherland@faa.gov. \n\n(l) Material Incorporated by Reference \n\n\n\t(1)The Director of the Federal Register approved the incorporation by reference (IBR) of the following service information under 5 U.S.C. 552(a) and 1 CFR part 51. \n\t(2) You must use the following service information to do the actions required by this AD, unless the AD specifies otherwise. \n\t(i) Boeing Special Attention Service Bulletin 777-32-0083, Revision 1, dated February 17, 2011. \n\t(3) 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; Internet https://www.myboeingfleet.com. \n\t(4) 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\t(5) 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 an NARA facility, call 202-741-6030, or go to http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.

Discussion \n\n\n\tWe 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 published in the Federal Register on December 30, 2011 (76 FR 82210). That NPRM proposed to require an inspection for the part number of the fuse pin, and replacement of the pin if necessary. \n\nComments \n\n\n\tWe gave the public the opportunity to participate in developing this AD. The following presents the comments received on the proposal (76 FR 82210, December 30, 2011) and the FAA's response to each comment. \n\nRequest To Revise the Compliance Time and Include Revised Service Information \n\n\n\tBoeing and United Airlines requested that we revise the NPRM (76 FR 82210, December 30, 2011) to refer to Boeing Special Attention Service Bulletin 777-32-0083, Revision 2 (not yet released). Boeing stated that it had performed a new risk-based assessment and found that 18 months is adequate to mitigate the remaining fleet risk. Boeing requested the compliance time be changed to 18 months from the date of the service bulletin. Also, Boeing requested that we provide credit for actions accomplished in accordance with Boeing Special Attention Service Bulletin 777-32-0083, Revision 1, dated February 17, 2011. \n\tWe partially agree. We agree to update the compliance time to 18 months based on the new risk-based safety assessment. We revised paragraphs (g), (g)(2), and (g)(3) of this AD to reflect an initial compliance time of 18 months. We disagree with delaying issuance of the final rule to reference Boeing Special Attention Service Bulletin 777- 32-0083, Revision 2, because that service information is not published at this time. Operators may request approval of an alternative method of compliance (AMOC) once Revision 2 of Boeing Special Attention Service Bulletin 777-32-0083 is released. \n\nConclusion \n\n\n\tWe 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 and minor editorial changes. We have determined that these minor changes: \n\tAre consistent with the intent that was proposed in the NPRM (76 FR 82210, December 30, 2011) for correcting the unsafe condition; and \n\tDo not add any additional burden upon the public than was already proposed in the NPRM (76 FR 82210, December 30, 2011). \n\tWe also determined that these changes will not increase the economic burden on any operator or increase the scope of the AD. \n\nCosts of Compliance \n\n\n\tWe estimate that this proposed AD affects 35 airplanes of U.S. registry. \n\tWe estimate the following costs to comply with this AD: \n\n\n\tEstimated Costs ---------------------------------------------------------------------------------------------------------------- \n\tCost per Cost on U.S. \n\tAction Labor cost Parts cost product operators ---------------------------------------------------------------------------------------------------------------- Inspection............................. 4 work-hours x $85 per $0 $340 $11,900 \n\thour = $340. ---------------------------------------------------------------------------------------------------------------- \n\n\n\tWe estimate the following costs to do any necessary pin replacements that would be required based on the results of the inspection. We have no way of determining the number of aircraft that might need these replacements: \n\n\n\tOn-Condition Costs ---------------------------------------------------------------------------------------------------------------- \n\tAction Labor cost Parts cost Cost per product ---------------------------------------------------------------------------------------------------------------- Pin replacement..................... 1 work-hour x $85 per $769 per pin........... $854 per pin. \n\thour = $85 per pin. ---------------------------------------------------------------------------------------------------------------- \n\nAuthority for This Rulemaking \n\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\tWe 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. \n\nRegulatory Findings \n\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\tFor the reasons discussed above, I certify that this AD: \n\t(1) Is not a ''significant regulatory action'' under Executive Order 12866, \n\t(2) Is not a ''significant rule'' under the DOT Regulatory Policies and \n\n((Page 37783)) \n\nProcedures (44 FR 11034, February 26, 1979), \n\t(3) Will not affect intrastate aviation in Alaska, and \n\t(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. \n\nList of Subjects in 14 CFR Part 39 \n\n\n\tAir transportation, Aircraft, Aviation safety, Incorporation by reference,Safety.