# AD 78-05-07: Main Landing Gear

- Type: Airworthiness directive
- Status: Current
- Products: Sikorsky S-61N
- Effective: April 13, 1978
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- Amendment: 39-3147
- Registered aircraft: 45 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/EA9535EF7E1E22EE86256A56004B0F83.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/78-05-07

## The airworthiness directive

78-05-07 SIKORSKY: Amendment 39-3147. Applies to Model S-61N rotorcraft prior to and including Sikorsky Serial No. 61805.

Compliance required within the next 300 hours time in service after the effective date of this AD, unless already accomplished.

To prevent inadvertent landing gear retraction, modify the main landing gear electrical system in accordance with Sikorsky Service Bulletin 61B55-40 or later FAA approved revision.

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 Sikorsky Aircraft, Commercial Customer Service, Stratford, Connecticut 06602. These documents may also be examined at the Office of the Regional Counsel, New England Region, Federal Aviation Administration, 12 New England Executive Park, Burlington, Massachusetts 01803.

This amendment becomes effective April 13, 1978.

## 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 1 of 4 models: S-61N

## 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: 45 (45 by airframe model, 0 by engine model)
- Makers: Sikorsky 45

Models with the most aircraft:

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

All 1 models: https://openairdocs.org/ad/78-05-07/models.md
Every aircraft: https://openairdocs.org/ad/78-05-07/aircraft.md

Its text cites no advisory circulars or STCs.

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