AD/EC 135/14 Direct Current Distribution Separation of Wiring (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.

Eurocopter EC 135 Series Helicopters

AD/EC 135/14 Direct Current Distribution - Separation
of Wiring 8/2007

Applicability:	EC135, all models, and EC635T1, serial numbers (S/N) 0005 up to and including S/N 0497, except S/N 0028, 0473, 0484, 0492 and 0496.
Requirement:	Modify and separate the direct-current (DC) power supply lines in accordance with the accomplishment instructions of Eurocopter Deutschland EC135 Alert Service Bulletin (ASB) EC135-24A-013 Revision 01 dated 25 May 2007.
Actions accomplished before the effective date of this Directive, in accordance with the original issue of Eurocopter Deutschland EC135 ASB EC135-24A-013 dated 12 December 2006, are acceptable for compliance with this Directive.
Note:  EASA AD 2007-0165 refers.
Compliance:	At the next periodical inspection, after the effective date of this Directive, but not later than 31 December 2007.
This Airworthiness Directive becomes effective on 2 August 2007.
Background:	Under current design regulations JAR-27 and JAR-29, power lines and signal lines may not be routed within one wire harness.  Additionally, redundant energy sources may not interfere with each other and must independently supply the aircraft with power.
In order to achieve compliance with the design rules, this Directive requires the power lines to be routed in a sufficient distance to each other and to the signal lines.

David Punshon
Delegate of the Civil Aviation Safety Authority

19 June 2007