# AD 76-20-02: Second Stage Fan Blades

- Type: Airworthiness directive
- Status: Current
- Products: Pratt & Whitney Division JT8D-1, JT8D-1A, JT8D-1B, JT8D-7, JT8D-7A and JT8D-7B
- Effective: October 10, 1976
- Superseded by: Nothing supersedes this AD
- Product type: Engine
- Amendment: 39-2734
- Registered aircraft: 90 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/6D2D7AD6637CB2D88625685B0073130F.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/76-20-02

## The airworthiness directive

76-20-02 PRATT & WHITNEY AIRCRAFT: Amendment 39-2734. Applies to all Pratt & Whitney Aircraft JT8D-1, -1A, -1B, -7, -7A, and -7B engines. Compliance required prior to June 30, 1978, unless already accomplished. To preclude liberation of second stage fan blades: A. Inspect the blade retaining strap for taper wear in accordance with Section 72-33-1 of Pratt & Whitney Aircraft JT8D Series Engine Manual P/N 481672, Revision 78, or later FAA approved revision or equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA, New England Region. Remove from service, second stage fan blades with taper wear in excess of .0025 inch before further flight. B. Install second stage fan blade bumper, P/N 642409, in accordance with Pratt & Whitney Aircraft Service Bulletin 2406 or later FAA approved revision or equivalent method approved by the Chief, Engineering and Manufacturing Branch, FAA, New England Region. Upon request of the operator, an FAA maintenance inspector, subject to prior approval of the Chief, Engineering and Manufacturing Branch, FAA, New England Region, may adjust the compliance date in this AD to permit compliance at an established inspection period of the operator if the request contains substantiating data to justify the increase for that operator. The manufacturer's service bulletins identified and described in this directive 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 these documents from the manufacturer may obtain copies upon request to Pratt & Whitney Aircraft, 400 Main Street, East Hartford, Connecticut 06108. 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, and at Federal Aviation Administration Headquarters, 800 Independence Avenue, S.W., Washington, D.C. 20591. Ahistorical file on this AD which includes the incorporated material in full is maintained by the Federal Aviation Administration at its headquarters in Washington, D.C., and at the New England Regional Office in Burlington, Massachusetts. This amendment becomes effective on October 10, 1976.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS E2EA](https://openairdocs.org/tcds/E2EA): Pratt & Whitney; names 6 of 16 models: JT8D-1, JT8D-7, JT8D-7A, JT8D-1B, JT8D-1A, JT8D-7B

## Registered aircraft it may apply to (OpenAirDocs)

Matched by airframe and engine model; the AD's applicability may narrow it by serial number, part number or equipment.

- Aircraft: 90 (0 by airframe model, 90 by engine model)
- Makers: Mcdonnell Douglas 78, Boeing 10, Douglas 2

Models with the most aircraft:

- [Pratt & Whitney JT8D series](https://openairdocs.org/engine/pratt-whitney-jt8d-series): 82 aircraft (engine model)
- [Pratt & Whitney JT8D-1](https://openairdocs.org/engine/pratt-whitney-jt8d-1): 8 aircraft (engine model)

All 2 models: https://openairdocs.org/ad/76-20-02/models.md
Every aircraft: https://openairdocs.org/ad/76-20-02/aircraft.md

Its text cites no advisory circulars or STCs.

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