AD/A330/64 Engine Fire Extinguishing Bottle Pipe (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.

Airbus Industrie A330 Series Aeroplanes

AD/A330/64 Engine Fire Extinguishing Bottle Pipe 12/2006

Applicability:

AIRBUS A330 aircraft - All serial numbers up to 755 inclusive.

This AD is not applicable to aircraft on which the four engine fire extinguishing bottles (2 per engine pylon) have been removed and re-installed at the opportunity of hydrostatic test of engine fire extinguishing as per Maintenance Review Board Report (MRB R) task 26.21.00/04.

Requirement:

Perform a detailed visual inspection on LH and RH engine pylons, for all 4 engine fire extinguisher bottles (2 per engine pylon), for the presence of the retaining ring on the discharge head of the bottles and if necessary apply the corrective actions, in accordance with AIRBUS Service Bulletin (SB) A330-26A3037 dated 26 July 2006 or later EASA approved revisions.

Note:  EASA Airworthiness Directive 2006-0297 dated 29 September 2006 refers.

Compliance:

Within 900 Flight Hours from the effective date of this AD.

This Airworthiness Directive becomes effective on 23 November 2006.

Background:

One A330 operator discovered that the line connection to the discharge head could not be properly secured during engine fire bottle replacement, due to a missing retaining-ring.  Inspections revealed that all 4 discharge-heads line connectors (2 per engine) were missing the retaining-ring. It was confirmed later that it was a quality issue.

The function of the retaining-ring is to secure a tight connection between the fire-extinguishing line and the discharge head.  In absence of the retaining-ring, in case of activation of the fire extinguishing system, the pressure exerted by the agent on the pipe could compromise the tightness of the connection, leading to an incomplete discharge of the extinguishing agent in the fire-zone.

This situation, if not corrected, can lead in the worst case, in combination with an engine fire, to a temporary uncontrolled engine fire which constitutes an unsafe condition.

This AD mandates a one time detailed visual inspection for the presence of the retaining ring on the discharge head assembly of engine fire extinguishing system.

James Coyne
Delegate of the Civil Aviation Safety Authority

12 October 2006