AD/PMC/12 Amdt 3 Propeller Hub Replacement Cancelled (Cth)

AIRWORTHINESS DIRECTIVE

On the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive AD/PMC/12 Amdt 3.

Propellers - Variable Pitch - McCauley

AD/PMC/12 Amdt 3 Propeller Hub - Replacement 4/2009

Requirement:

CANCELLED.

This AD is cancelled on 9 April 2009.

Background:

This unique Australian AD was originally raised in1968 requiring an inspection for circumferential cracking of both propeller blade sockets of the rear positioned propeller of Cessna 336 aircraft following local experience of cracking and loss of a propeller blade.  Applicable propellers were all McCauley D2AF34C56 and D2AF34C61 models.  Subsequent amendments to this AD reduced the applicable TIS threshold from 1,000 hours to 500 hours, removal from service of the hubs of propeller models D2AF34C56 series, introduction of applicability to include Cessna 337; subsequently removed, and provided for shot peening propeller hubs of models D2AF34C61 series propellers prior to model D2AF34C61-J by incorporating AD/PMC/20 (SB 88) that allowed re-use of the propeller hub.  AD/PMC/20 was cancelled in 2004.

Compliance was before propeller hub exceeds 500 hours TTIS.

Given the extended period this AD has been promulgated and containing superseded requirements, and that affected propeller hubs would have been inspected rejected or reworked by now, this AD is considered to be no longer required.

James Coyne
Delegate of the Civil Aviation Safety Authority

17 February 2009