# AD 58-08-04: Pitch Locks

- Type: Airworthiness directive
- Status: Current
- Products: Hamilton Standard Division 232, 242, 34D, 34E, 43E and 43H
- Superseded by: Nothing supersedes this AD
- Product type: Propeller
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/5B2DD44F2011295A862569700062C7E3.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/58-08-04

## The airworthiness directive

58-08-04 HAMILTON STANDARD: Applies to all Models 23260, 24260, 34D50, 34D51, 34E60, 43E60, and 43H60 Propellers Incorporating Pitch Locks.

Compliance required at first propeller overhaul after May 15, 1958, if not already accomplished.

Two cases have been reported wherein the dome cap of propellers incorporating a pitch lock become partially disengaged in flight, resulting in complete loss of propeller control.

To preclude additional failures of this nature, reduce to 0.013 or less the clearance between the dome cap and stop lever sleeve bushing by conducting the necessary inspection rework, and/or replacement.

(Hamilton Standard Service Bulletin No. 496D covers this same subject.)

This supersedes AD 58-02-02.

## Affected data sheets (6) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS P-853](https://openairdocs.org/tcds/P-853): Hamilton Standard Division; names 1 of 1 models: 232
- [TCDS P-856](https://openairdocs.org/tcds/P-856): Hamilton Standard Division; names 1 of 1 models: 34D
- [TCDS P-870](https://openairdocs.org/tcds/P-870): Hamilton Standard Division; names 1 of 1 models: 242
- [TCDS P-871](https://openairdocs.org/tcds/P-871): Hamilton Standard Division; names 1 of 1 models: 43E
- [TCDS P-881](https://openairdocs.org/tcds/P-881): Hamilton Standard Division; names 1 of 1 models: 34E
- [TCDS P-887](https://openairdocs.org/tcds/P-887): Hamilton Standard Division; names 1 of 1 models: 43H

## Registered aircraft it may apply to (OpenAirDocs)

No registered aircraft matched the models it names.

Its text cites no advisory circulars or STCs.

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