Ad/AMD 50/38 - Electrical Power Feeder Inspection (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.

AMD Falcon 50 and 900 Series Aeroplanes

AD/AMD 50/38 Electrical Power Feeder Inspection 11/2006

Applicability:	Mystère-Falcon 900 aeroplanes, serial number (S/N) 188 through 202 inclusive, except those on which Dassault Aviation Service Bulletins (SB) F900-358 and F900-359 both dated 19 October 2005 have both already been implemented or Modification M3891 has already been incorporated.
Falcon 900EX aeroplanes, S/N 82 through 146 inclusive, except those on which Dassault Aviation SB F900EX-241 and F900EX-251 both dated 19 October 2005 have both already been implemented or Modification M3891 has already been incorporated.
Requirement:	1.    Mystère-Falcon 900 aeroplanes -
a.     Inspect and protect the feeder from the right side partition wall at frames 22/23 in accordance with SB F900-358 or later EASA approved revision.
b.    If the feeder is found damaged, accomplish all applicable related corrective actions specified in the Accomplishment Instructions of SB F900-359 or later EASA approved revision.
c.     Modify the right side partition wall at frames 22/23 and protect and/or repair the feeder cable as instructed in the SB F900-359 or later EASA approved revision.
Implementation of both SB F900-358 and SB F900-359 or later EASA approved revision is considered to be a terminating action for the requirements of this Directive.
2.    Falcon 900EX aeroplanes -
a.     Inspect and protect the feeder from the right side partition wall at frames 22/23 in accordance with SB F900EX-241 or later EASA approved revision.
b.    If the feeder is found damaged, accomplish all applicable related corrective actions specified in the Accomplishment Instructions of the SB F900EX-251 or later EASA approved revision.
c.     Modify the right side partition wall at frames 22/23 and repair the feeder cable as instructed in the SB F900EX-251 or later EASA approved revision.

Implementation of both SB F900EX-241 and SB F900EX-251 or later EASA approved revision is considered to be a terminating action for the requirements of this Directive.
Note:  EASA AD 2006-0270 refers.
Compliance:	For Requirement 1 -
a.     Within either 330 hours time in service (TIS) or seven months after the effective date of this Directive, whichever occurs first.
b.    Before further flight after the Requirement 1.a. inspection.
c.     At the first time the partition wall is removed, but no later than 3,750 flight cycles or 74 months after from the effective date of this Directive, whichever occurs first.
For Requirement 2 -
a.     Within either 330 hours TIS or seven months after the effective date of this Directive, whichever occurs first.
b.    Before further flight after the Requirement 1.a. inspection.
c.     At the first time the partition wall is removed, but no later than 3,750 flight cycles or 74 months after from the effective date of this Directive, whichever occurs first.
This Airworthiness Directive becomes effective on 26 October 2006.
Background:	The aircraft manufacturer has advised of the discovery of potential chafing between the electrical wire feeder bundle and the right side partition wall separating the cabin from the lavatory at frames 22/23.  This chafing may damage the feeder bundle and cause a sustained smoke-generating short-circuit between the feeder and the partition wall made of resistive composite material.  Smoke and a difficult-to-localize short-circuit may result in a hazardous situation.

James Coyne
Delegate of the Civil Aviation Safety Authority

15 September 2006