# AD 67-20-01: Retention Bolts

- Type: Airworthiness directive
- Status: Current
- Products: Pacific Propeller A6441FN-606
- Effective: August 23, 1967
- Superseded by: Nothing supersedes this AD
- Product type: Propeller
- Amendment: 39-466
- FAA DRS: https://drs.faa.gov/browse/excelExternalWindow/2EBE1F522A443BA686256E01005461AC.0001
- DRS record last changed: May 30, 2024
- Page: https://openairdocs.org/ad/67-20-01

## The airworthiness directive

67-20-01 ALLISON - AERO PRODUCTS: Amdt. No. 39-439 as revised Amdt. 39-466, Part 39, Federal Register June 29, 1967. Applies to Models A6441FN-606 and A6441FN-606A Propellers.

Compliance required as indicated, unless already accomplished.

To prevent serious overspeeds and to make the propeller pitch lock more effective under remote combinations of critical component failures, accomplish the following:

  (a) On or before November 1, 1967, install Part No. 6859637 restrictor in the increase pitch port of each hub island, as outlined in Allison Commercial Service Letter CSL 189, Pages 14 and 15, Paragraph C2b(1)(2)(3) and (4), entitled "Hub Assembly - Preparation for Assembly."

  (b) On or before November 1, 1967, remove the eight master gear retention bolts and install eight P/N 6859881 bolts as replacements, as outlined in Allison's Commercial Propeller Bulletin, CPB No. 63-317.

This amendment effective August 23, 1967.

Revised August 23, 1967.

## Affected data sheets (1) (OpenAirDocs)

The type certificate data sheets whose models the AD names.

- [TCDS P-898](https://openairdocs.org/tcds/P-898): Pacific Propeller Inc.; names 1 of 1 models: A6441FN-606

## 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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