# AD 71-24-02: Failure of Transmission Mount Strut

- Type: Airworthiness directive
- Status: Current
- Products: FH1100 Manufacturing 1100 and FH-1100
- Effective: November 24, 1971
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- Amendment: 39-1334
- Registered aircraft: 8 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/B2776FA501D5D3ED86256A38005FD266.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/71-24-02

## The airworthiness directive

71-24-02 FAIRCHILD HILLER ROTORCRAFT: Amdt. 39-1334. Applies to Model 1100 and FH-1100 Type Helicopters certificated in all categories.

Compliance required as indicated.

To preclude fatigue failure of the transmission mount strut, P/N 24-28031, due to internal corrosion, accomplish the following:

Within the next 30 days after the effective date of this AD, unless already accomplished replace P/N 24-28031 left side, lateral, adjustable transmission strut with P/N 24-28031-11 strut in accordance with Section 28 of the FH-1100 Service Manual or an alternate method approved by the Chief, Engineering & Manufacturing Branch, FAA, Eastern Region. Upon installation of MS-21252 fork fitting apply RTV-102 sealant or equivalent to the threads of fitting and under AN316-5R retaining nut.

This amendment is effective November 24, 1971.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS H2WE](https://openairdocs.org/tcds/H2WE): Air Space Design and Manufacturing LLC; names 2 of 2 models: 1100, FH-1100

## 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: 8 (8 by airframe model, 0 by engine model)
- Makers: Fairchild Hiller 8

Models with the most aircraft:

- [Fairchild Hiller FH-1100](https://openairdocs.org/model/fairchild-hiller-fh-1100): 8 aircraft (airframe model)

All 1 models: https://openairdocs.org/ad/71-24-02/models.md
Every aircraft: https://openairdocs.org/ad/71-24-02/aircraft.md

Its text cites no advisory circulars or STCs.

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