AD 88-03-52

88-03-52 PRATT & WHITNEY: Amendment 39-5957. Final copy of Telegraphic AD. Applies to Pratt & Whitney (PW) PW2037 and PW2040 turbofan engines.

Compliance is required as indicated, unless already accomplished. To prevent compressor and turbine case cooling air valve tube and 2.5 bleed valve actuator tube cracking that can lead to fuel leaks, substantial fuel quantity loss and possible engine fire, accomplish the following:

(a) For the engines operated in any of the following configurations: (1) with the Fuel Quantity Indication System (FQIS) inoperative under the provisions specified in the Boeing 757 aircraft Master Minimum Equipment List (MMEL), Item 28-41-1; (2) with one of the Fuel Quantity Processor (FQP) Channels inoperative under the provisions specified in the MMEL, Item 28-41-2; (3) with both Flight Management Computer (FMC) Systems inoperative under the provisions specified in the MMEL, Item 34-61-1; or (4) with the FQIS functional, both FQP Channels functional, and at least one FMC System functional, but operating without the provisions of Boeing Operations Manual Bulletin (OMB) Number 87-7, Revision 1, dated October 28, 1987, accomplish the following prior to further flight:

(a)(i) Compressor and turbine case cooling air valve tube clamping configuration: Remove loop clamp bracket assembly Part Number (P/N) 1B2224-01 from compressor and turbine case cooling air valve tubes, and install a clamping configuration that clamps the tubes to a bracket spanning the pressure and return tubes in accordance with Accomplishment Instructions contained in PW Alert Service Bulletin (ASB) Number PW2000 A75-36, dated October 28, 1987.

(a)(ii) 2.5 bleed valve actuator tubes and manifold assembly clamping configuration: Install a new bracket and clamp configuration in accordance with the applicable part of the Accomplishment Instructions contained in PW ASB Number PW2000 A75-38, dated December 21, 1987.

(b) For engines operated with the FQIS functional, both FQP Channels functional, at least one FMC System functional, and in accordance with the provisions of Boeing OMB Number 87-7, Revision 1, dated October 28, 1987, accomplish items (a)(i) and (a)(ii) above within 250 hours in service from the effective date of this AD.

(c) Aircraft may be ferried in accordance with the provisions of FAR 21.197 and 21.199 to a base where the AD can be accomplished.

(d) Upon request, an equivalent means of compliance with the requirements of this AD may be approved by the Manager, Engine Certification Office, Aircraft Certification Division, Federal Aviation Administration, New England Region, 12 New England Executive Park, Burlington, Massachusetts 01803.

(e) Upon submission of substantiating data by an owner or operator through an FAA airworthiness inspector, the Manager, Engine Certification Office, New England Region, may adjust the compliance time specified in this AD.

Pratt & Whitney ASB's NO. PW2000 A75-36, dated October 28, 1987, and NO. PW2000 A75-38, dated December 21, 1987, identified and described in this document are 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 the engine manufacturer's ASB's may obtain copies upon request to Pratt & Whitney, Publication Department, P.O. Box 611, Middletown, Connecticut 06457.

These documents may also be examined at the Office of the Regional Counsel, Federal Aviation Administration, New England Region, 12 New England Executive Park, Burlington, Massachusetts 01803, Room 311, Rules Docket Number 88-ANE-02, between the hours of 8:00 a.m. and 4:30 p.m., Monday through Friday, except federal holidays.

This amendment, 39-5957, becomes effective on July 13, 1988, as to all persons except those persons to whom it was made effective 24 hours after receipt by individual Telegraphic AD T88-03-52, issued January 29, 1988, which contained this amendment.