86-10-01 PRATT & WHITNEY: Amendment 39-5292. Applies to Pratt & Whitney (PW) JT9D-3A series turbofan engines.
Compliance is required as indicated, unless already accomplished.
To preclude second stage turbine disk failures resulting from rearward deflection of the second stage turbine nozzle guide vane inner shroud, inspect second stage nozzle guide vanes, Part Number (P/N) 770372, in accordance with the Accomplishment Instructions of PW Alert Service Bulletin (ASB) 5619, dated July 31, 1985, or FAA approved equivalent, per the following schedule:
(a) Inspect vanes for rearward deflection prior to accumulating 4,000 hours in service since new or since the vanes were refurbished, and reinspect thereafter per paragraph (b).
(b) Reinspect at the following intervals and until such time as the engine incorporates a complete set of new or refurbished vanes with zero time in service, at which time the requirements of paragraph (a) become applicable.
(1) Within the next 1,000 hours in service since last inspection, if the vane deflection is greater than 0.050 inches but not greater than 0.070 inches.
(2) Within the next 2,000 hours in service since last inspection, if the vane deflection is less than or equal to 0.050 inches.
(c) Remove from service, prior to further flight, vanes that have a rearward deflection greater than 0.070 inches.
NOTES: 1. Refurbished vanes are defined as vanes which have been operated in service and have subsequently been inspected and repaired to the specifications in Pratt & Whitney Engine Manual, P/N 646028.
2. Engine Manuals P/N 646028 and 770407 are identical for the JT9D-3A engine model and are both FAA approved.
Upon request, an equivalent means of compliance may be approved by the Manager, Engine Certification Office, Aircraft Certification Division, New England Region, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803.
Aircraft may be ferried in accordance with the provisions of FAR Sections 21.197 and 21.199 to a base where the AD can be accomplished.
Upon submission of substantiating data by an owner or operator through the FAA maintenance inspector, the Manager, Engine Certification Office, New England Region, may adjust the compliance time specified in this AD.
PW ASB 5619, dated July 31, 1985, is incorporated herein and made a part hereof pursuant to 5 U.S.C. 552(a)(1). All persons affected by this directive who have not already received this document from the manufacturer may obtain copies upon request to Pratt & Whitney, Publication Department, P.O. Box 611, Middletown, Connecticut 06457.
This document also may be examined at the Office of the Regional Counsel, New England Region, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803, Rules Docket Number 85-ANE-22, Room Number 311, between the hours of 8:00 a.m. and 4:30 p.m., Monday though Fridayexcept Federal holidays.
This amendment becomes effective on June 5, 1986.