91-07-11 BOEING: Amendment 39-6946. Docket No. 90-NM-211-AD. \n\n\tApplicability: Model 727 series airplanes, listed in Boeing Alert Service Bulletin 727-53A0199, dated July 5, 1990, certificated in any category. \n\n\tCompliance: Required as indicated, unless previously accomplished. \n\n\tTo prevent failure of the No. 2 cargo doorway frames and depressurization of the airplane, accomplish the following: \n\n\tA.\tPrior to accumulating 22,000 total flight cycles or within the next 500 flight cycles after the effective date of this AD, whichever occurs later, conduct either of the following inspections in accordance with Figure 1 of Boeing Alert Service Bulletin 727-53A0199, dated July 5, 1990, or Revision 1, dated November 29, 1990: \n\n\t\t1.\tConduct a visual inspection and an eddy current inspection of the No. 2 cargo doorway forward and aft frames for cracks. Repeat the visual inspections and eddy current inspections at intervals not to exceed 3,000 flight cycles. \n\t\n\t\t\t\t\tOr2.\tConduct a visual inspection of the No. 2 cargo doorway forward and aft frames for cracks. Repeat the visual inspection at intervals not to exceed 500 flight cycles, until an eddy current inspection for cracks in the affected area is accomplished. Perform the eddy current inspection within the next 3,000 flight cycles after the effective date of this AD. Thereafter, repeat the visual inspections and eddy current inspections at intervals not to exceed 3,000 flight cycles. \n\n\tB.\tIf cracks are found, prior to further flight, repair in accordance with Boeing Alert Service Bulletin 727-53A0199, dated July 5, 1990, or Revision 1, dated November 29, 1990. \n\n\tC.\tIncorporation of repairs in accordance with Figure 2 or modification in accordance with Figure 3 of Boeing Alert Service Bulletin 727-53A0199, dated July 5, 1990, or Revision 1, dated November 29, 1990, constitutes terminating action for the inspection requirements of paragraph A. of this AD. \n\n\tD.\tAn alternative method ofcompliance 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 forwarded through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, 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 SW., Renton, Washington. \n\n\tThis amendment (39-6946, AD 91-07-11) becomes effectiveon April 29, 1991.