Commonwealth legislation

AD/PHZL/58 - Piston Nut B474

RepealedCTH

This Act has been repealed and is no longer in force. It is retained for historical reference.

Jurisdiction

Commonwealth

Collection

legislative instrument

Plain English Summary

3/10 complexity

This Airworthiness Directive mandates inspections and a permanent modification for Shorts SD3-60-300 aircraft fitted with Hartzell HC-A6A-3 propellers because the B-474 piston nut may not fully contact the piston, risking uncommanded pitch change and loss of thrust/control.

Operators must inspect and index the parts within 100 flight hours from 19 May 1989 (or by 9 June 1989) with repeating 100‑hour checks until the propeller is modified per the service bulletin at overhaul or by 30 June 1991.

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Current sections

Direct links to the current provisions in AD/PHZL/58 - Piston Nut B474.

AD/PHZL/58 - Piston Nut B474

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 107 CIVIL AVIATION SAFETY AUTHORITY

SCHEDULE OF AIRWORTHINESS DIRECTIVES

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Propellers - Variable Pitch - Hartzell

AD/PHZL/58 Piston Nut B474 7/89 DM Applicability: All Hartzell propellers model HC-A6A-3 installed on Shorts SD3-60-300 aircraft. Requirement: 1. Action in accordance with Procedure 1 of Hartzell SB No 163.

Action in accordance with Procedure 2 of Hartzell SB No 163.

Compliance: For Requirement 1. Within 100 hours time in service from 19 May 1989, or by 9 June 1989 whichever occurs first. Thereafter re-inspect at intervals not exceeding 100 hours time in service until propeller is modified in accordance with Requirement 2.

For Requirement 2. At next propeller overhaul or by 30 June 1991, whichever occurs first.

Background: The manufacturer has advised that the B-474 nut may not fully contact the piston when correctly torqued and could cause an inadvertent blade angle change. Pending introduction of a new nut indexing of relevant parts is required.

Source text

Sourced from the Federal Register of Legislation (legislation.gov.au), CC BY 4.0.

1 AD/PHZL/58 - Piston Nut B474

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 107 CIVIL AVIATION SAFETY AUTHORITY

SCHEDULE OF AIRWORTHINESS DIRECTIVES

Propellers - Variable Pitch - Hartzell

Action in accordance with Procedure 2 of Hartzell SB No 163.

For Requirement 2. At next propeller overhaul or by 30 June 1991, whichever occurs first.