AD 99-13-05 Airworthiness Directives; Boeing Model 777 Series Airplanes

Models named: 777 series. Read the applicability below — it usually turns on serial or part numbers too.

Model 777 series airplanes, as listed in Boeing Alert Service Bulletin 777-57A0008, dated March 25, 1999; certificated in any category. Note 1: This AD applies to each airplane identified in the preceding applicability provision, regardless of whether it has been modified, altered, or repaired in the area subject to the requirements of this AD. For airplanes that have been modified, altered, or repaired so that the performance of the requirements of this AD is affected, the owner/operator must request approval for an alternative method of compliance in accordance with paragraph (f) of this AD. The request should include an assessment of the effect of the modification, alteration, or repair on the unsafe condition addressed by this AD; and, if the unsafe condition has not been eliminated, the request should include specific proposed actions to address it.

Required as indicated, unless accomplished previously. To detect and correct fatigue cracking of the outboard support of the flaperon, which could result in fracture of the flaperon support structure, loss of the flaperon, and consequent reduced controllability of the airplane; accomplish the following: Repetitive Inspections (a) Perform high frequency eddy current (HFEC) inspections to detect fatigue cracking of the upper cutout and lower flange of the outboard support assembly of the flaperons on the left and right wings, in accordance with Part 1 of the Accomplishment Instructions of Boeing Alert Service Bulletin 777-57A0008, dated March 25, 1999, at the time specified in paragraph (a)(1) or (a)(2) of this AD, as applicable. (1) For airplanes identified as Group 1 in the alert service bulletin: Perform HFEC inspections prior to the accumulation of 10,000 total flight cycles, or within 225 flight cycles after the effective date of this AD, whichever occurs later. Repeat the inspections thereafter at intervals not to exceed 225 flight cycles. (2) For airplanes identified as Group 2 in the alert service bulletin: Perform HFEC inspections prior to the accumulation of 4,000 total flight cycles, or within 70 flight cycles after the effective date of this AD, whichever occurs later. Repeat the inspections thereafter at intervals not to exceed 70 flight cycles. Corrective Action (b) If any fatigue cracking is detected during any inspection required by paragraph (a) of this AD: Prior to further flight, concurrently accomplish the modifications specified in Parts 2 and 3 of the Accomplishment Instructions of Boeing Alert Service Bulletin 777-57A0008, dated March 25, 1999. Accomplishment of the modifications constitutes terminating action for the repetitive inspection requirements of this AD. [[Page 33392]] (c) If any fatigue cracking is detected, and Boeing Alert Service Bulletin 777-57A0008, dated March 25, 1999, specifies that corrective actions may be accomplished in accordance with an operator's ``equivalent procedure:'' The actions must be accomplished in accordance with the chapter of the Boeing 777 Airplane Maintenance Manual (AMM) specified in the alert service bulletin. Optional Terminating Action (d) Concurrent accomplishment of the modifications specified in Parts 2 and 3 of the Accomplishment Instructions of Boeing Alert Service Bulletin 777-57A0008, dated March 25, 1999, constitutes terminating action for the repetitive inspections required by this AD. Spares (e) As of the effective date of this AD, no person shall install any part identified in the ``Existing Part Number'' column of Section 2.E. of Boeing Alert Service Bulletin 777-57A0008, dated March 25, 1999, on any airplane. Alternative Methods of Compliance (f) An alternative method of compliance or adjustment of the compliance time that provides an acceptable level of safety may be used if approved by the Manager, Seattle Aircraft Certification Office (ACO), FAA, Transport Airplane Directorate. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may add comments and then send it to the Manager, Seattle ACO. Note 2: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO. Special Flight Permits (g) Special flight permits may be issued in accordance with sections 21.197 and 21.199 of the Federal Aviation Regulations (14 CFR 21.197 and 21.199) to operate the airplane to a location where the requirements of this AD can be accomplished. Incorporation by Reference (h) The actions shall be done in accordance with Boeing Alert Service Bulletin 777-57A0008, dated March 25, 1999. This incorporation by reference was approved by the Director of the Federal Register in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. Copies may be obtained from Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124-2207. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue, SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street, NW., suite 700, Washington, DC. (i) This amendment becomes effective on July 8, 1999. Issued in Renton, Washington, on June 10, 1999. Dorenda D. Baker, Acting Manager, Transport Airplane Directorate, Aircraft Certification Service. [FR Doc. 99-15778 Filed 6-22-99; 8:45 am] BILLING CODE 4910-13-P