# AD 84-19-08: Engine Mount

- Type: Airworthiness directive
- Status: Current
- Products: Hiller UH-12D, UH-12E and UH-12E-L with STC SH177WE or SH178WE
- Effective: September 20, 1984
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- Amendment: 39-4914
- Registered aircraft: 129 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/EC825FA5087C388786256A4E0043D3DE.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/84-19-08

## The airworthiness directive

84-19-08 HILLER HELICOPTERS, a subsidiary of Rogerson Aircraft Corp (formerly Hiller Aviation): Amendment 39-4914. Applies to Model UH-12D and UH-12E series helicopters equipped with engine mount Part No. 63181-5 certificated in any category which have been converted to turbine power by STC SH177WE or SH178WE.

Compliance is required as indicated (unless already accomplished).

  (a) Within the next 20 hours time in service after the effective date of this AD, and thereafter at intervals not to exceed 600 hours time in service from the last inspection, remove the paint from the outer gimbal forward attach fitting of the Hiller engine mount Part No. 63181-5 and dye penetrant or magnetic particle inspect the gusset weld beads for cracks on both the front and back sides of the gusset.

  (b) If cracks are found, replace the engine mount Part No. 63181-5 before further flight.

  (c) Prior to or immediately following installation or reinstallation of engine mount Part No.63181-5 in any of the Model UH-12 series helicopters listed above, perform the inspection required by paragraph (a) of this AD.

  (d) Alternative inspections, modifications, or other actions which provide an equivalent level of safety may be used when approved by the Manager, Seattle Aircraft Certification Office, FAA, 17900 Pacific Highway South, C-68966, Seattle, Washington 98168.

This supersedes Amendment 39-3538 (44 FR 50035; August 27, 1979), AD 79-18-01. This amendment becomes effective September 20, 1984.

## Affected data sheets (2) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

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

## 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: 129 (129 by airframe model, 0 by engine model)
- Makers: Hiller 126, 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 UH-12E-L](https://openairdocs.org/model/hiller-uh-12e-l): 1 aircraft (airframe model)
- [Hiller-Rogerson Helicopter UH12E](https://openairdocs.org/model/hiller-rogerson-helicopter-uh12e): 1 aircraft (airframe model)

All 6 models: https://openairdocs.org/ad/84-19-08/models.md
Every aircraft: https://openairdocs.org/ad/84-19-08/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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