92-17-04 BOEING: Amendment 39-8333. Docket No. 91-NM-235-AD. Supersedes AD 91-18-09, Amendment 39-8012. \n\n\tApplicability: Model 757 series airplanes, equipped with brake part numbers (P/N) identified in paragraphs (a) and (c) of this AD, certificated in any category. \n\n\tCompliance required as indicated, unless accomplished previously. \n\n\tTo prevent loss of main landing gear braking effectiveness, accomplish the following: \n\n\t(a)\tWithin 180 days after November 12, 1991 (the effective date of Amendment 39-8012, AD 91-18-09), incorporate the maximum brake wear limits, shown below, into the FAA-approved maintenance inspection program. \n\n\n\nBrake Mfr.\nBrake P/N\nBoeing P/N\nMax. Wear Limit \nDunlop\t\nAHA 1301\nS160N020-1\n2.46 inches \nDunlop\t\nAHA 1637\nS160N020-5\n2.46 inches \nDunlop\t\nAHA 1676\nS160N020-7\n2.46 inches\nDunlop\t\nAHA 1693\nS160N020-8\n2.46 inches \nDunlop\t\nAHA 1884\nS160N020-14\n2.80 inches\nBFGoodrich\n2-1510\nS160N020-11\n1.70 inches \n\n\t(b)\tFor BFGoodrich brake P/N 2-1510 (Boeing P/N S160N020-11), in lieu of the limit specified in paragraph (a) of this AD, the maximum allowable brake wear may be extended to 2.2 inches when it is placed into the FAA-approved maintenance inspection program. \n\n\t(c)\tWithin 180 days after the effective date of this AD, accomplish the following: \n\n\t\t(1)\tFor airplanes equipped with BFGoodrich Brake P/N's 2-1457 and 2-1457-1, (Boeing P/N S160N010-43 AND S160N010-45): Accomplish the procedures specified in Section 2.B.(1) of BFGoodrich Service Bulletin 2-1457-32-13, dated January 30, 1991, or Revision 1, dated December 16, 1991 (issued February 28, 1991). Brakes found worn more than the 1.4-inch allowable brake wear must be removed and replaced, prior to further flight, with either a brake built in accordance with Section 2.B.(1)c. of the service bulletin, or a brake with more than 1.4 inches of allowable wear remaining. \n\n\t\t(2)\tFor airplanes equipped with BFGoodrich Brake P/N's 2-1457, 2-1457-1,and 2-1457-2, (Boeing P/N S160N010-43, S160N010-45, and S160N010-46): Incorporate either Figure 1 and/or Figure 2 of Section 2.B.(1)c. of BFGoodrich Service Bulletin 2-1457-32-13, dated January 30, 1991, or Revision 1, dated December 16, 1991 (issued February 28, 1991), into the FAA-approved maintenance inspection program. \n\n\t(d)\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. Operators shall submit their requests through an appropriate FAA Principal Maintenance Inspector, who may concur or comment and then send it to the Manager, Seattle ACO. \n\n\tNOTE: Information concerning the existence of approved alternative methods of compliance with this AD, if any, may be obtained from the Seattle ACO. \n\n\t(e)\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(f)\tThe procedures relative to BFGoodrich Brake P/N's 2-1457 and 2-1457-1, and 2-1457-2 shall be done in accordance with BFGoodrich Service Bulletin 2-1457-32-13, dated January 30, 1991; or BFGoodrich Service Bulletin 2-1457-32-13, Revision 1, dated December 16, 1991 (issued February 28, 1991). This incorporation by reference was approved by the Director of the Federal Register 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; and BFGoodrich Aerospace, Aircraft Wheels and Brakes, P.O. Box 340, Troy, Ohio 45373. Copies may be inspected at the FAA, Transport Airplane Directorate, 1601 Lind Avenue SW., Renton, Washington; or at the Office of the Federal Register, 800 North Capitol Street NW., 7th Floor, Suite 700, Washington, DC. \n\n\t(g)\tThis amendment becomes effective on September 28, 1992.