# AD 73-25-03: Finite Life Components

- Type: Airworthiness directive
- Status: Current
- Products: Hiller UH-12D
- Effective: January 10, 1974
- Superseded by: Nothing supersedes this AD
- Product type: Aircraft, Rotorcraft
- Amendment: 39-1752
- Registered aircraft: 24 may be affected, by airframe or engine model (OpenAirDocs)
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/508676EB36ABF13786256A38005FFFA8.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/73-25-03

## The airworthiness directive

73-25-03 HILLER AVIATION: Amdt. 39-1752. Applies to Hiller UH-12D helicopters certificated in all categories.

Compliance required prior to further flight for all UH-12D helicopters which have been converted from the military version (H-23D) before the effective date of this AD, and at the time of conversion for those helicopters which are converted to the UH-12D after the effective date of this AD.

To insure safe service life for the finite life components of the Hiller Model UH-12D Helicopters, accomplish the following:

Replace the finite life components listed in Hiller Aviation's UH-12D Inspection Guide, Airworthiness Limitations Section, dated November 5, 1973, at the times specified therein with new or serviceable parts.

NOTE: A copy of the finite life components list can be obtained from Hiller Aviation, 2075 West Scranton Avenue, Porterville, California, 93257, or from the FAA, Aircraft Engineering Division, P. O. Box 92007, World Way Postal Center, Los Angeles, California 90009.

This amendment becomes effective January 10, 1974.

## Affected data sheets (1) (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

## 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: 24 (24 by airframe model, 0 by engine model)
- Makers: Hiller 22, Hiller-Osborn 2

Models with the most aircraft:

- [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)

All 2 models: https://openairdocs.org/ad/73-25-03/models.md
Every aircraft: https://openairdocs.org/ad/73-25-03/aircraft.md

Its text cites no advisory circulars or STCs.

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