88-12-06 BOEING: Amendment 39-5936. Applies to Model 767 series airplanes, listed in Boeing Service Bulletin 767-53-0025, dated June 4, 1987, certificated in any category. \n\n\tCompliance required within 12 months after the effective date of this AD, unless previously accomplished. \n\n\tTo prevent structural failure of the vertical fin in the event of a failure of the aft pressure bulkhead, accomplish the following: \n\n\tA.\tInstall seal plates over the electrical wiring and hydraulic tubing cutouts on the fin-to-body skin in accordance with Boeing Service Bulletin 767-53-0025, dated June 4, 1987. \n\n\tB.\tAn 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\tC.\tSpecial 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 the requirements 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 the Boeing Commercial Airplane Company, 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, 39-5936, becomes effective July 1, 1988.