# AD 77-03-06: Compressor Front Hubs

- Type: Airworthiness directive
- Status: Current
- Products: Pratt & Whitney Division JT8D-1, JT8D-1A, JT8D-1B, JT8D-7, JT8D-7A and JT8D-7B
- Effective: February 25, 1977
- Superseded by: Nothing supersedes this AD
- Product type: Engine
- Amendment: 39-2828
- Registered aircraft: 90 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/ECF91255CA63F1058625685E0071A9BA.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/77-03-06

## The airworthiness directive

77-03-06 PRATT & WHITNEY AIRCRAFT: Amendment 39-2828. Applies to Pratt & Whitney Aircraft JT8D-1, -1A, -1B, -7, -7A, and -7B engine front compressor front hub, P/N 504101, with serial numbers listed in Table 1 of Pratt & Whitney Aircraft Alert Service Bulletin 4661, dated October 15, 1976.

Compliance required as indicated on front compressor front hubs that have accumulated 6,000 cycles or more in service to preclude failure from lack of shotpeening.

Inspect by visual or eddy current method, in accordance with P&WA ASB 4661, dated October 15, 1976, or later FAA approved revision, the rear face and overhung shelf of the front compressor front hub for cracks emanating out of the base of the blade slot, within the next 150 cycles in service unless already accomplished. Reinspect at 150 cycle intervals if by visual method, or at 400 cycle intervals if by eddy current method. If a crack is found during any inspection, replace the hub before further flight.

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 inspection intervals specified 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 bulletin identified and described in this directive 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 these documents from the manufacturer may obtain copies upon request to Pratt & Whitney Aircraft, Division of United Technologies Corporation, 400 Main Street, East Hartford, Connecticut 06108. These documents may also be examined at Federal Aviation Administration, New England Region, 12 New England Executive Park, Burlington, Massachusetts 01803, and at FAA Headquarters, 800 Independence Avenue, S.W., Washington, D.C. A historical file on this AD which includes the incorporated material in full is maintained by the FAA at its headquarters in Washington, D.C., and at New England Region.

This amendment becomes effective February 25, 1977.

## 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/77-03-06/models.md
Every aircraft: https://openairdocs.org/ad/77-03-06/aircraft.md

Its text cites no advisory circulars or STCs.

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