# AD 76-20-06: Cable Freezing Control

- Type: Airworthiness directive
- Status: Current
- Products: Hiller UH-12D and UH-12E with STC SH177WE or SH178WE
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- Amendment: 39-2740
- Registered aircraft: 128 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/203138DBBF0D247B86256A3800601881.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/76-20-06

## The airworthiness directive

76-20-06 HILLER AVIATION: Amendment 39-2740. Applies to Model UH-12D and UH-12E Helicopters which have been converted to turbine power in accordance with Soloy Conversions, Limited, STC Nos. SH177WE and SH178WE respectively certificated in all categories. Compliance required as indicated.

To prevent loss of helicopter control due to freezing of the governor cable, throttle cable, and/or anti-ice cable accomplish the following:

      (A) Within 15 days time in service after the receipt of this telegraphic AD, install a placard in view of the pilot which states:

"Flight in outside air temperature of 32 degrees F. or lower is prohibited."

      (B) Within 60 days time in service after the receipt of this telegraphic AD, perform the modifications contained in Soloy Conversions, Ltd., Service Bulletin 01-560 dated September 3, 1976, or later FAA approved revisions.

      (C) The operation restriction prescribed in (A) above may be discontinued and the placard may be removed when the control cable modifications required by (B) above have been completed.

      (D) Equivalent procedures may be approved by the Chief, Engineering and Manufacturing Branch, FAA Northwest Region, upon the submission of adequate substantiating data.

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 Soloy Conversions, Limited, P. O. Box 60, Chehalis, Washington 98532. These documents may also be examined at FAA Northwest Region, 9010 East Marginal Way South, Seattle, Washington.

This amendment becomes effective upon publication in the Federal Register for all persons except those to whom it was made effective immediately by telegram dated September 8, 1976.

## Affected data sheets (2) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS 4H10](https://openairdocs.org/tcds/4H10): Siam Hiller Holdings Inc.; names 1 of 1 models: UH-12D
- [TCDS 4H11](https://openairdocs.org/tcds/4H11): Siam Hiller Holdings Inc.; names 1 of 2 models: UH-12E

## 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: 128 (128 by airframe model, 0 by engine model)
- Makers: Hiller 125, Hiller-Osborn 2, Hiller-Rogerson Helicopter 1

Models with the most aircraft:

- [Hiller UH-12E](https://openairdocs.org/model/hiller-uh-12e): 103 aircraft (airframe model)
- [Hiller UH-12D](https://openairdocs.org/model/hiller-uh-12d): 22 aircraft (airframe model)
- [Hiller-Osborn UH-12D](https://openairdocs.org/model/hiller-osborn-uh-12d): 2 aircraft (airframe model)
- [Hiller-Rogerson Helicopter UH12E](https://openairdocs.org/model/hiller-rogerson-helicopter-uh12e): 1 aircraft (airframe model)

All 5 models: https://openairdocs.org/ad/76-20-06/models.md
Every aircraft: https://openairdocs.org/ad/76-20-06/aircraft.md

## Related documents

- [STC SH177WE](https://openairdocs.org/stc/SH177WE): Installation of Allison 250-C20/250-C20B engine and related changes.. Siam Hiller Holdings Inc, Named in the applicability
- [STC SH178WE](https://openairdocs.org/stc/SH178WE): Installation of Allison 250-C20/250-C20B engine and related changes. (UH-12E-L (4 place)). Siam Hiller Holdings Inc, Named in the applicability

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