# AD 77-24-03: Fuel Control Valve

- Type: Airworthiness directive
- Status: Current
- Products: Hiller UH-12C, UH-12D, UH-12L, UH-12L4, UH-12E and UH-12E-L
- Effective: January 6, 1978
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- Amendment: 39-3088
- Registered aircraft: 168 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/A772BC40770B19E086256A38006031D0.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/77-24-03

## The airworthiness directive

77-24-03 HILLER HELICOPTERS: Amendment 39-3088. Applies to Hiller Model UH-12C, D, E (4 place), L, E-L, and L4's certificated in all categories incorporating control levers P/N 72229 or 72210. All aircraft serial numbers up to No. 5024 are included. S/N 5024 and subsequent will have the guard installed at the time of manufacture.

  (a) To prevent hazardous engine power loss from inadvertent shutoff of the fuel control valve, within the next 100 hours time in service after the effective date of this AD, install a guard on the fuel shutoff valve handle in accordance with the instructions described in Paragraph 2B in Hiller Service Bulletin No. 72-1 dated June 17, 1977, or later FAA approved revision.

  (b) Equivalent methods of fabrication and installation of a guard on the fuel shutoff valve handle may be used when approved by the Chief, Aircraft Engineering Division, FAA Western Region.

  (c) Special flight permits may be issued in accordance with FAR's 21.197 and 21.199 to operate helicopters to a base for accomplishment of the modification required by Paragraph (a) of this AD.

This amendment becomes effective January 6, 1978.

## Affected data sheets (4) (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 H1WE](https://openairdocs.org/tcds/H1WE): Siam Hiller Holdings Inc.; names 2 of 2 models: UH-12L4, UH-12L
- [TCDS 4H10](https://openairdocs.org/tcds/4H10): Siam Hiller Holdings Inc.; names 1 of 1 models: UH-12D
- [TCDS 6H2](https://openairdocs.org/tcds/6H2): Siam Hiller Holdings Inc.; names 1 of 2 models: UH-12C

## 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: 168 (168 by airframe model, 0 by engine model)
- Makers: Hiller 160, Hiller - World Helicopters 2, Hiller-Osborn 2, Hiller-Felt 1, Hiller-Rogerson Helicopter 1, Hiller-Stanley 1, Hiller-Trident Helicopters 1

Models with the most aircraft:

- [Hiller UH-12E](https://openairdocs.org/model/hiller-uh-12e): 103 aircraft (airframe model)
- [Hiller UH-12C](https://openairdocs.org/model/hiller-uh-12c): 31 aircraft (airframe model)
- [Hiller UH-12D](https://openairdocs.org/model/hiller-uh-12d): 22 aircraft (airframe model)
- [Hiller UH-12L4](https://openairdocs.org/model/hiller-uh-12l4): 3 aircraft (airframe model)
- [Hiller - World Helicopters UH-12C](https://openairdocs.org/model/hiller-world-helicopters-uh-12c): 2 aircraft (airframe model)
- [Hiller-Osborn UH-12D](https://openairdocs.org/model/hiller-osborn-uh-12d): 2 aircraft (airframe model)
- [Hiller-Stanley UH-12C](https://openairdocs.org/model/hiller-stanley-uh-12c): 1 aircraft (airframe model)
- [Hiller-Felt UH-12C](https://openairdocs.org/model/hiller-felt-uh-12c): 1 aircraft (airframe model)
- [Hiller UH-12E-L](https://openairdocs.org/model/hiller-uh-12e-l): 1 aircraft (airframe model)
- [Hiller-Trident Helicopters UH-12C](https://openairdocs.org/model/hiller-trident-helicopters-uh-12c): 1 aircraft (airframe model)
- [Hiller-Rogerson Helicopter UH12E](https://openairdocs.org/model/hiller-rogerson-helicopter-uh12e): 1 aircraft (airframe model)

All 12 models: https://openairdocs.org/ad/77-24-03/models.md
Every aircraft: https://openairdocs.org/ad/77-24-03/aircraft.md

Its text cites no advisory circulars or STCs.

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