# AD 78-02-01: Main Landing Gear

- Type: Airworthiness directive
- Status: Current
- Products: Piper PA-31T and PA-31T1
- Effective: May 9, 1979
- Published: May 7, 1979
- Issued: April 25, 1979
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Small airplane
- Amendment: 39-3460
- Registered aircraft: 151 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/C34FB2078EA6D76C86256E120055A0BC.0001
- DRS record last changed: November 21, 2025
- Page: https://openairdocs.org/ad/78-02-01

## The airworthiness directive

78-02-01 PIPER AIRCRAFT CORPORATION: Amendment 39-3124 as amended by amendment 39-3460. Applies to model PA-31T airplanes, serial numbers 31T-7400002 through 31T-7820077, and Model PA-31T1 airplanes, serial numbers 31T-7804001 through 31T-780-4006, certificated in all categories. Compliance required within the next fifty hours in service after the effective date of this AD, unless already accomplished.

  (a) To preclude possible failure of the main landing gear actuating cylinder rod end bearing assemblies, accomplish the inspection and replacement where required, described in the "Instruction" portion of Piper Aircraft Corporation Service Bulletin No. 57A, dated August 30, 1978.

  (b) Equivalent alterations or methods of compliance must be approved by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region.

  (c) Upon submission of substantiating data by an owner or operator, through an FAA maintenance inspector, the compliance time specified in this AD may be adjusted by the Chief, Engineering and Manufacturing Branch, FAA Eastern Region.

Amendment 39-3124 was effective January 18, 1978.

This amendment 39-3460 is effective May 9, 1979.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS A8EA](https://openairdocs.org/tcds/A8EA): Piper Aircraft Inc.; names 2 of 6 models: PA-31T, PA-31T1

## 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: 151 (151 by airframe model, 0 by engine model)
- Makers: Piper 151

Models with the most aircraft:

- [Piper PA-31T](https://openairdocs.org/model/piper-pa-31t): 87 aircraft (airframe model)
- [Piper PA-31T1](https://openairdocs.org/model/piper-pa-31t1): 64 aircraft (airframe model)

All 2 models: https://openairdocs.org/ad/78-02-01/models.md
Every aircraft: https://openairdocs.org/ad/78-02-01/aircraft.md

Its text cites no advisory circulars or STCs.

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