AD/EMB-145/11 APU Firewall (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.

Embraer EMB-135 and EMB-145 Series Aeroplanes

AD/EMB-145/11 APU Firewall 8/2008

Applicability:

Model EMB-145 aircraft, serial numbers 145004 through 145019.

Requirement:

Inspect the APU firewall for cracks in accordance with Part I of EMBRAER Service Bulletin No. 145-53-0004, or later CTA/ANA approved revision.

Note:  Installation of the vibration damper in accordance with Part II of the Requirement document constitutes terminating action to the inspection requirement of this Directive.

Compliance:

At intervals not to exceed 100 flight hours; until Part II of the Requirement document is accomplished.

This Airworthiness Directive becomes effective on 31 July 2008.

Background:

Reports were received of cracks in the shell spot welded area of EMB-145 aircraft APU firewalls.  Undetected cracking could affect the structural integrity and sealing function of the firewall.

David Villiers
Delegate of the Civil Aviation Safety Authority

17 June 2008