# AD 71-05-01: Main Landing Gear Axle

- Type: Airworthiness directive
- Status: Current
- Products: Sikorsky S-61A, S-61D, S-61E, S-61L, S-61N, S-61NM, S-61R and S-61V
- Effective: February 23, 1971
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- Amendment: 39-1157
- Registered aircraft: 54 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/E1688313A69A006186256A55006DD061.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/71-05-01

## The airworthiness directive

71-05-01 SIKORSKY: Amdt. 39-1157. Applies to S-61 Type Helicopters Certified in all Categories.

Compliance required as follows:

To preclude the possibility of failure of the S-61 Main Landing Gear Axle, P/N 6125-50115-0, unless already accomplished, inspect and replace the axle in accordance with paragraph 2, Accomplishment Instructions of Sikorsky Service Bulletin 61B25-3 dated 15 January 1971 or later FAA-approved revision or an alternate method approved by the Chief, Engineering and Manufacturing Branch, FAA, Eastern Region.

Report results of above inspection in compliance with this AD to Chief, Engineering and Manufacturing Branch, FAA, Eastern Region (Reporting Approved by Bureau of the Budget under BOB No. 04-R0174.)

Replacement axle P/N S6125-50115-2 has a service life of 242,550 landings.

This amendment is effective February 23, 1971.

## Affected data sheets (2) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 1H15](https://openairdocs.org/tcds/1H15): Sikorsky Aircraft; names 4 of 4 models: S-61R, S-61N, S-61L, S-61NM
- [TCDS H2EA](https://openairdocs.org/tcds/H2EA): Sikorsky Aircraft Corporation; names 4 of 4 models: S-61A, S-61D, S-61V, S-61E

## 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: 54 (54 by airframe model, 0 by engine model)
- Makers: Sikorsky 53, Carson Helicopters / Sikorsky 1

Models with the most aircraft:

- [Sikorsky S-61N](https://openairdocs.org/model/sikorsky-s-61n): 45 aircraft (airframe model)
- [Sikorsky S-61A](https://openairdocs.org/model/sikorsky-s-61a): 5 aircraft (airframe model)
- [Sikorsky S-61L](https://openairdocs.org/model/sikorsky-s-61l): 1 aircraft (airframe model)
- [Sikorsky S-61NM](https://openairdocs.org/model/sikorsky-s-61nm): 1 aircraft (airframe model)
- [Sikorsky S-61R](https://openairdocs.org/model/sikorsky-s-61r): 1 aircraft (airframe model)
- [Carson Helicopters / Sikorsky S61A](https://openairdocs.org/model/carson-helicopters-sikorsky-s61a): 1 aircraft (airframe model)

All 6 models: https://openairdocs.org/ad/71-05-01/models.md
Every aircraft: https://openairdocs.org/ad/71-05-01/aircraft.md

Its text cites no advisory circulars or STCs.

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