AD/AB139/2 Engine Fire Extinguisher Bottles (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/AB139/2 Engine Fire Extinguisher Bottles 13/2007 DM

Applicability:	AB139 model helicopters with serial numbers (S/N) 31005 to 31054 except 31007 and AW139 model helicopters with S/N 31055 to 31067, 31070 and 31071.
Requirement:	1.    If not previously accomplished, verify the correct installation of electrical receptacles/connectors on the fire extinguisher bottles in accordance with Agusta Bollettino Tecnico (BT) 139-085 dated 18 May 2007 or later revision approved by the Italian Ente Nazionale per l’Aviazione Civile (ENAC).
2.    If, as a result of the Requirement 1 verification, any discrepancy is detected with the fire bottle electrical connector installation, replace the defective fire bottle in accordance with BT 139-085 or later revision approved by the ENAC.
Note:  ENAC AD 2007-227 Revision 1 refers.
Compliance:	For Requirement 1 - Within 30 days after the effective date of this Directive.
For Requirement 2 - Before further flight after the Requirement 1 verification inspection.
This Airworthiness Directive becomes effective on 10 November 2007.
Background:	The ENAC has advised that during an installation of a fire extinguisher bottle part number 3G2620V00131 on a new helicopter, it was found that the connectors on the bottle were swapped between engines one and two.
This condition, if not corrected, might cause the extinguishing agent to discharge into the incorrect engine when the system is activated.  This Directive requires the fire bottles to be inspected and, if necessary, replaced.

David Punshon
Delegate of the Civil Aviation Safety Authority

29 October 2007