89-07-15: Engine Strut Diagonal Brace Lugs

89-07-15 BOEING: Amendment 39-6167.\n\n\tApplicability: Model 747 series airplanes, listed in Boeing Service Bulletin 747-54-2126, dated June 16, 1988, certificated in any category.\n\n\tCompliance: Required as indicated, unless previously accomplished.\n\n\tTo prevent failure of the engine strut diagonal brace lugs, accomplish the following:\n\n\tA. Prior to the accumulation of 10,000 landings or 8 years in service, whichever occurs first; or within the next 3 months after the effective date of this AD, whichever occurs later, ultrasonically inspect engine strut diagonal brace lugs for cracks, in accordance with Boeing Service Bulletin 747-54-2126, dated June 16, 1988.\n\n\tB. If cracking is found, prior to further flight, replace the diagonal brace with a new or overhauled diagonal brace incorporating the terminating action described by paragraph D., below, in accordance with Boeing Service Bulletin 747-54-2126, dated June 16, 1988.\n\n\tC. If no cracking is found, repeat the inspection required by paragraph A., above, at intervals not to exceed 1,000 landings.\n\n\tD. Terminating action for the inspections required by paragraphs A. and C., above, consists of removing existing bushings, oversizing bores to remove corrosion, installing high-interference fit bushings with wet sealant, and fillet sealing bushing flanges, in accordance with Boeing Service Bulletin 747-54-2126, dated June 16, 1988.\n\n\tE. An alternate means of compliance or adjustment of the compliance time, which provides an acceptable level of safety, may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, Northwest Mountain Region.\n\n\tNOTE: The request should be forwarded through an FAA Principal Maintenance Inspector (PMI), who may add any comments and then send it to the Manager, Seattle Aircraft Certification Office.\n\n\tF. Special flight permits may be issued in accordance with FAR 21.197 and 21.199 to operate airplanes to a base in order to comply with therequirements of this AD.\n\n\tAll persons affected by this directive who have not already received the appropriate service documents from the manufacturer may obtain copies upon request to Boeing Commercial Airplanes, P.O. Box 3707, Seattle, Washington 98124. These documents may be examined at the FAA, Northwest Mountain Region, 17900 Pacific Highway South, Seattle, Washington, or Seattle Aircraft Certification Office, FAA, Northwest Mountain Region, 9010 East Marginal Way South, Seattle, Washington.\n\n\tThis amendment (39-6167, AD 89-07-15) becomes effective on May 3, 1989.