# AD 75-26-10: Component Replacement

- Type: Airworthiness directive
- Status: Current
- Products: Sikorsky S-61L, S-61N and S-61NM
- Effective: January 2, 1976
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- Amendment: 39-2461
- Registered aircraft: 47 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/5F365749A3076BF786256A320065EF57.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/75-26-10

## The airworthiness directive

75-26-10 SIKORSKY AIRCRAFT: Amendment 39-2461. Applies to S-61L, S-61N, and S-61NM helicopters certificated in all categories.

Compliance required as indicated.

As a result of the completion of a recent engineering evaluation program and the development of additional substantiating data, a new schedule of replacement times has been established for the components of S-61 helicopters.

  (a) After the effective date of this AD, the replacement of S-61 components must be accomplished in accordance with the schedule of Section 2C of Sikorsky Service Bulletin No. 61B General-1F dated October 20, 1975, or later FAA approved revisions.

  (b) The manufacturer's specifications and procedures 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 Sikorsky Aircraft, Stratford, Connecticut 06602. These documents may also be examined at FAA, New England Region, 12 New England Executive Park, Burlington, Massachusetts 01803, and at FAA Headquarters, 800 Independence Avenue, S.W., Washington, D.C. 20591. 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 the FAA, New England Region, Burlington, Massachusetts.

This supersedes Amendment 39-1167 (36 F.R. 4689), AD 71-06-02 as amended by Amendment 39-1271 (36 F.R. 16186), Amendment 39-1948 (39 F. R. 31626), and Amendment 39-1978 (39 F.R. 34649).

This amendment becomes effective January 2, 1976.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 1H15](https://openairdocs.org/tcds/1H15): Sikorsky Aircraft; names 3 of 4 models: S-61N, S-61L, S-61NM

## 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: 47 (47 by airframe model, 0 by engine model)
- Makers: Sikorsky 47

Models with the most aircraft:

- [Sikorsky S-61N](https://openairdocs.org/model/sikorsky-s-61n): 45 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)

All 3 models: https://openairdocs.org/ad/75-26-10/models.md
Every aircraft: https://openairdocs.org/ad/75-26-10/aircraft.md

Its text cites no advisory circulars or STCs.

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