91-24-11 R1 BOEING: Amendment 39-8175. Docket No. 91-NM-114-AD. Revises AD 91- 24-11, Amendment 39-8097. \n\n\tApplicability: Model 727 series airplanes, line numbers 001 through 875, certificated in any category. \n\n\tCompliance: Required as indicated, unless previously accomplished. \n\n\tTo prevent failure of the body station (BS) 870 terminal fitting and depressurization of the airplane, accomplish the following: \n\n\t(a)\tPrior to the accumulation of 25,000 total flight cycles or within the next 3,000 flight cycles after the effective date of this AD, whichever occurs later, conduct visual, eddy current, and ultrasonic inspections of the body station (BS) 870 terminal fitting for cracks and web separations, in accordance with Figure 1 of Boeing Service Bulletin 727-53-0194, dated November 8, 1990. During the initial inspection, rework uncracked fastener holes and install oversized fasteners, in accordance with Figure 1 of the service bulletin. Removal of weather caulking material from the fuselage skin butt splice cavity, as shown in Figure 1 of the service bulletin, is not required by this AD. \n\n\t(b)\tIf cracks or separations are found, prior to further flight, repair the BS 870 terminal fitting in accordance with Boeing Service Bulletin 727-53-0194, dated November 8, 1990. After repairs, repeat the inspection requirements of paragraph (a) of this AD as follows: \n\n\t\t(1)\tFor airplanes on which outboard flange cracks are removed by oversizing the fastener holes, repeat the inspections at intervals not to exceed 6,000 flight cycles or 3 years, whichever occurs first. \n\n\t\t(2)\tFor airplanes on which the external doubler is used to repair only outboard flange cracks, repeat the inspections at intervals not to exceed 6,000 flight cycles or 3 years, whichever occurs first. \n\n\t\t(3)\tFor airplanes on which the external doubler is used to repair either web separations, or web separations and outboard flange cracks, repeat the inspections at intervals not toexceed 3,000 flight cycles or 18 months, whichever occurs first. \n\n\t(c)\tIf no cracks or separations are found, repeat the inspection requirements of paragraph (a) of this AD at intervals not to exceed 6,000 flight cycles or 3 years, whichever occurs first. \n\n\t(d)\tThe partial replacement of the body station (BS) 870 terminal fitting in accordance with Boeing Service Bulletin 727-53-0194, dated November 8, 1990, constitutes terminating action for the inspection requirements of this AD, for the replaced portion of the fitting. Unreplaced portions must continue to be inspected in accordance with this AD. \n\n\t(e)\tThe complete replacement of the body station (BS) 870 terminal fitting in accordance with Boeing Service Bulletin 727-53-0194, dated November 8, 1990, constitutes terminating action for the inspection requirements of this AD. \n\n\t(f)\tAn alternative method 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 forwarded through an FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Seattle ACO. \n\n\t(g)\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\t(h)\tThe inspection and repair requirements shall be done in accordance with Boeing Service Bulletin 727-53-0194, dated November 8, 1990. This incorporation by reference was previously approved by the Director of the Federal Register as of January 7, 1992 (56 FR 61354), 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. Copies may be inspected at the FAA, Northwest Mountain Region, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington; or at the Office of the Federal Register, 1100 L Street NW., Room 8401, Washington, DC. \n\n\t(i)\tThis amendment (39-8175), AD 91-24-11 R1, is effective on January 7, 1992.