90-20-14 BOEING: Amendment 39-6730. Docket No. 90-NM-25-AD. \n\n\tApplicability: Model 727 series airplanes, listed in Boeing Service Bulletin 727-53- 0068, Revision 4, dated September 14, 1989, certificated in any category. \n\n\tCompliance: Required as indicated, unless previously accomplished. \n\n\tTo detect cracks in the forward cargo compartment sidewall frames, accomplish the following: \n\n\tA.\tExcept as provided in paragraph B., below, within the next 2,000 flight cycles after the effective date of this AD, or prior to accumulating 15,600 total flight cycles, whichever occurs later, conduct a visual inspection of the forward cargo compartment sidewall frames for cracks, in accordance with the Accomplishment Instructions of Boeing Service Bulletin 727-53- 0068, Revision 4, dated September 14, 1989. Repeat the inspections at intervals not to exceed 9,000 flight cycles. \n\n\tB.\tRepair cracked structure prior to further flight, in accordance with the Accomplishment Instructions of the Boeing Service Bulletin, 727-53-0068, Revision 4, dated September 14, 1989, or earlier FAA-approved revisions. \n\n\tC.\tModification of the affected structure in accordance with the Accomplishment Instructions of Boeing Service Bulletin 727-53-0068, Revision 4, dated September 14, 1989, or earlier FAA-approved revisions, terminates the inspection requirements of paragraph A. of this AD. \n\n\tD.\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 (ACO), FAA, Transport Airplane Directorate. \n\n\tNOTE: The request should be submitted directly to the Manager, Seattle ACO, and a copy sent to the cognizant FAA Principal Inspector (PI). The PI will then forward comments or concurrence to the Seattle ACO. \n\n\tE.\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 Boeing Commercial Airplane Group, P.O. Box 3707, Seattle, Washington 98124. These documents may be examined at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue S.W., Renton, Washington. \n\n\tAirworthiness Directive 90-20-14 supersedes AD 83-02-08, Amendment 39-4548. \n\tAmendment 39-6730, AD 90-20-14, becomes effective on October 23, 1990.