AD/HS 125/175 Emergency Radio 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.

British Aerospace BAe 125 Series Aeroplanes

AD/HS 125/175 Emergency Radio Wiring 7/2005 DM

Applicability:	Hawker 800XP aeroplanes serial numbers 258541, 258556 and 258567 through 258608 inclusive.
Requirement:	1.    Perform a detailed inspection for damage (primarily but not limited to evidence of heat damage) of wiring in the flight compartment in accordance with Part 1 of the Accomplishment Instructions of Raytheon Service Bulletin (SB) 24-3555, Revision 1 dated June 2004.
Note 1:  For the purposes of this Directive, a detailed inspection is: “An intensive examination of a specific item, installation or assembly to detect damage, failure or irregularity.  A direct source of good lighting as well as inspection aids such as mirrors, magnifying lenses, etc., may be necessary.  Surfaces may also be required to be cleaned.”
2.    If damage is found in the wiring, repair in accordance with Part 1of the Accomplishment Instructions of SB 24-3555 Rev 1.
3.    Modify Emergency Radio Circuit as detailed in the Part 2 of the Accomplishment Instructions of SB 24-3555 Rev 1.
4.    Conduct functionality check of the emergency radio system.
5.    Revise Aircraft Fight Manual Emergency Procedure section by inserting Temporary Change P/N 140-590032-0005TC7.
Note 2:  FAA AD 2005-09-03 Amdt 39-14071 refers.
Compliance:	For Requirement 1 - Within 50 hours time in service (TIS) or 30 days, whichever occurs first, after the effective date of this Directive.
For Requirement 2 - Before further flight after Requirement 1 inspection.
For Requirement 3:
a.     If damage was found during the Requirement 1 inspection - Before further flight after the inspection.

b.    If damage was not found during the Requirement 1 inspection - Within 300 hours TIS or 180 calendar days after the effective date of this Directive.
For Requirement 4 - Before further flight after the Requirement 3 modification is accomplished.
For Requirement 5 - Before further flight after the Requirement 3 modification is accomplished.
This Airworthiness Directive becomes effective on 1 June 2005.
Background:	The United States Federal Aviation Administration (FAA) has advised of possible miswiring in the power distribution system, which could cause damage due to excessive current flow in the electrical circuit that could result in smoke or fire in the aircraft.

James Coyne
Delegate of the Civil Aviation Safety Authority

12 May 2005