AD/BELL 412/48 - Overhead Circuit Breaker Panels (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.

Bell Helicopter Textron 412 Series Helicopters AD/BELL 412/48 Overhead Circuit Breaker Panels 3/2006

Applicability: Agusta-Bell AB 412 helicopters. Requirement: If not previously accomplished, inspect and, if necessary, modify the overhead circuit breaker panels and wire harness installation in accordance with Agusta Alert Service Bulletin 412-81 dated 23 June 2000. Note: ENAC (Italy) AD 2000-331 refers. Compliance: Within 30 days after the effective date of this Directive. This Airworthiness Directive becomes effective on 16 March 2006. Background: The Ente Nazionale per l'Aviazione Civile (ENAC) of Italy has advised that an AB 412 operator has reported an electrical short circuit occurring with overheating and wires burning in the overhead circuit breaker panels.

This Directive requires the inspection and/or modification of the overhead circuit breaker panels to prevent chafing and interference between wire harnesses and structures or components.

James Coyne Delegate of the Civil Aviation Safety Authority

1 February 2006