89-10-07 PRATT & WHITNEY: Amendment 39-6181.
Applicability: Pratt & Whitney (PW) JT9D-3A, -7, -7A, -7AH, -7H, -7F, -7J, and -20 turbofan engines.
Compliance: Required as indicated, unless already accomplished.
To prevent a diffuser case Number 4 or Number 7 strut failure that can cause a Number 3 bearing compartment fire and subsequent nacelle fire, accomplish the following:
(a) Install strut insert assembly Part Number 804698-01 into both the Number 4 and Number 7 diffuser case struts, in accordance with the Accomplishment Instructions of PW Service Bulletin (SB) 5730, dated February 4, 1987, at the next engine shop visit after the effective date of this AD, but not later than August 31, 1991.
NOTE: For the purpose of this AD, engine shop visit is defined as maintenance entailing a separation of the high pressure compressor case and diffuser case "K" flange.
(b) Aircraft may be ferried in accordance with the provisions of FAR 21.197 and 21.199 toa base where the AD may be accomplished.
(c) Upon submission of substantiating data by an owner or operator through an FAA Airworthiness Inspector, an alternative method of compliance with the requirements of this AD or adjustment to the compliance times specified in this AD may be approved by the Manager, Engine Certification Office, ANE-140, Engine and Propeller Directorate, Aircraft Certification Service, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803.
The diffuser case strut insert incorporation shall be done in accordance with PW SB 5730, dated February 4, 1987. 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 Pratt & Whitney, Publication Department, P.O. Box 611, Middletown, Connecticut 06457. Copies may be inspected at the Regional Rules Docket, Office of the Assistant Chief Counsel, Federal AviationAdministration, New England Region, 12 New England Executive Park, Room 311, Burlington, Massachusetts 01803, or at the Office of the Federal Register, 1100 L Street, N.W., Room 8301, Washington, DC.
This amendment (39-6181, AD 89-10-07) becomes effective on May 30, 1989.