T91-17-51 BOEING: Docket No. 91-NM-178-AD. Telegraphic AD issued on August 15, 1991. \n\tApplicability: Model 767 series airplanes equipped with Pratt and Whitney PW4000, General Electric CF6-80C2, or Rolls Royce RB211-524 series engines, certificated in any category. \n\n\tCompliance: Required as indicated, unless previously accomplished. \n\n\tTo prevent potential in-flight thrust reverser deployments, within 7 days after receipt of this AD, accomplish the following: \n\n\t(a)\tDeactivate both left and right thrust reversers in accordance with Section 78-31-1 of Boeing Document D630T002, "Boeing 767 dispatch deviation guide," Revision 9, dated May 1, 1991. \n\n\t(b)\tAdd the following to the limitations section of the FAA-approved Airplane Flight Manual (AFM): \n\n\t"REDUCE BY FIVE PERCENT THE AVAILABLE ACCELERATE-STOP DISTANCE RESULTING FROM THE AIRPLANE FLIGHT MANUAL TAKEOFF PERFORMANCE ANALYSIS WHEN THE RUNWAY IS WET OR CONTAMINATED." \n\n\tThis may be accomplished by placing a copyof this AD in the AFM.\n \n\t(c)\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(d)\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\tTelegraphic AD T91-17-51, issued on August 15, 1991, supersedes Amendment 39- 7073, AD 91-15-09, and is effective immediately upon receipt.