AD/PFP/19 Blade Leading Edge Protection (Cth)

AIRWORTHINESS DIRECTIVE

For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.001(1) of CASR 1998.  The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.

Propellers - Fixed Pitch

AD/PFP/19 Blade Leading Edge Protection 4/2007

Applicability:

All MT- fixed pitch propellers manufactured before 1995 and not overhauled since April 1994.

Requirement:

1.    Inspect the propeller blade leading edge metallic erosion sheath for proper bonding, in accordance with the publications in reference.  Failure of the bond may be indicated by cracks or looseness of the metallic sheath.

2.    Replace any propeller blade with a de-bonded or loose metallic sheath.

3.    Inspect the propeller blade leading edge polyurethane (PU) protective strip, in accordance with the publications in reference.

4.    Replace any damaged or missing PU protective strip.

Note 1:  The inspection detailed in Requirements 1 and 3 may be performed by the pilot at the pre-flight inspection interval only.

Note 2:  Reference Publications are as follows:

MT-propeller Service Bulletin No. 8B dated March 8, 2006 or later approved revisions.

Operation and Installation Manual E-112, issue November 1993 or later;

Operation and Installation Manual E-118, issue March 1994 or later;

Operation and Installation Manual E-124, issue March 1994 or later;

Operation and Installation Manual E-148, issue March 1994 or later;

Operation and Installation Manual E-309, issue March 1994 or later.

Note 3:  EASA AD 2006-0345 dated 14 November 2006 refers.

Compliance:

1.    During each pre-flight inspection and each “100-hours” inspection.

2.    Before the next flight.

3.    During each pre-flight inspection and each “100-hours” inspection.

4.    Within 10 flight hours.

Note 4:  Any damaged or missing PU strips can be recorded in the maintenance log by the pilot for replacement within the flight time required in Compliance 4.

This Airworthiness Directive becomes effective on 12 April 2007.

Background:

Before 1995, the inspection of the propeller blade leading edges was not sufficiently detailed in the Instructions for Continuing Airworthiness.  This detailed inspection is necessary to prevent the sudden loss of the blade leading edge metallic erosion sheath which could result in person injury and damage to the aircraft.

David Punshon
Delegate of the Civil Aviation Safety Authority

21 February 2007