AD/AB139/5 - Exhaust Tailpipe Assembly (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.

Agusta AB139 and AW139 Series Helicopters AD/AB139/5 Exhaust Tailpipe Assembly 4/2008

Applicability: AB 139 and AW 139 helicopters, all serial numbers, except 31002, 31003, 31004 and 31007, if equipped with Tailpipe Assemblies having Part Number (P/N) 3G7800L00131 (LH) or 3G7800L00231 (RH). Requirement: 1. For AB 139 helicopters - inspect the tailpipe assembly in accordance with the instructions of Agusta BT 139-069 Revision A dated 8 November 2006 or later approved revision.

2. For AW 139 helicopters - inspect the tailpipe assembly in accordance with the instructions of Agusta BT 139-069 Revision A or later approved revision.

3. If heat damage or cracks are found in the exhaust area residing inside the cowling, replace the damaged tailpipe assembly with an airworthy part in accordance with the Agusta AW139 Aircraft Maintenance Publication (AMP).

4. If cracks are found in the exhaust area residing outside the cowling that turn off abruptly from the original direction or are outside the allowable limits established by Agusta BT 139-069 Rev. A, or later approved revision, replace the cracked tailpipe assembly with an airworthy part in accordance with the Agusta AW139 Aircraft Maintenance Publication. (AMP).