AD/Do 328/19 Propeller Blade Overheat 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.

Dornier 328 Series Aeroplanes

AD/DO 328/19 Propeller Blade Overheat Protection 1/2006

Applicability:

Model 328-100 aeroplanes with serial numbers 3005 to 3050 inclusive.

Requirement:

1.     If not previously accomplished, remove from service de-icing system timer part number (P/N) A-5639-2 or 4E2947-2 and replace it with in timer P/N A-5639-3 or 4E2947-3 in accordance with the Accomplishment Instructions of Dornier Service Bulletins SB-328-30-164, dated 30 April 1996.

2.     De-icing system timers P/N A-5639-2 or 4E2947-2 may not be installed on any aeroplane as a replacement spare.

Note:  LBA AD 1999-027 refers.

Compliance:

For Requirement 1 - Within 30 days after the effective date of this Directive.

For Requirement 2 - As of the effective date of this Directive.

This Airworthiness Directive becomes effective on 19 January 2006.

Background:

The German Luftfahrt-Bundesamt (LBA) has received advice from the aircraft manufacturer that a short circuit in of the propeller or airframe de-ice wiring together with a subsequent failure of de-ice timer/monitor could result in a propeller blade overheat.  This overheating may result even if the aircraft de-ice switch is in the “OFF” position.

This Directive requires the replacement of de-ice timers and prohibits the use of certain timers as replacement spares.

James Coyne
Delegate of the Civil Aviation Safety Authority

29 November 2005