AD/A320/229 Ram Air Turbine Ejection Jack (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 A319, A320 and A321 Series Aeroplanes

AD/A320/229 Ram Air Turbine Ejection Jack 1/2009

Applicability:

AIRBUS A318, A319, A320 and A321aircraft, equipped with HAMILTON SUNDSTRAND (formerly DOWTY) Ram Air Turbine (RAT) Ejection Jack, Model ERPS13EJ, Part Number (P/N) 114160004A or 114160005.

Aircraft having received AIRBUS modification 27189 in production or AIRBUS Service Bulletin (SB) A320-29-1100 in service, and without having received AIRBUS modification 28413 in production, are not affected by the requirements of this AD.

Requirement:

1.    Identify the Serial Number (S/N) of the installed Ejection Jack of the RAT and, if included in the affected batch, replace it with a modified or reworked Ejection Jack in accordance with AIRBUS SB A320-29-1136.

2.    Do not install RAT Ejection Jack Model ERPS13EJ, P/N 114160004A or 114160005 on an aeroplane unless it has been modified or reworked in accordance with AIRBUS SB A320-29-1136.

The use of later approved revisions of this document is acceptable for compliance with the requirements of this AD.

Note:  EASA AD 2008-0199 dated 5 November 2008 refers.

Compliance:

For Requirement 1 - Within 12 months after the effective date of this AD, unless previously accomplished.

For Requirement 2 - After the effective date of this AD.

This Airworthiness Directive becomes effective on 15 January 2009.

Background:

An A320 operator experienced difficulties in extending the RAT during a deployment testing.  During the trouble shooting, the Ejection Jack of the RAT was removed and investigated.  The investigation identified excessive wear of the uplock segments against the inner cylinder of the Ejection Jack, due to an incorrect blend radius of the inner cylinder.  This problem was determined to be caused during the previous rework of the Ejection Jack and was possible due to the incomplete requirements contained within the Component Maintenance Manual (CMM).

This Ejection Jack failure may prevent the effective deployment and use of the RAT in emergency conditions.  This AD therefore mandates the replacement of an Ejection Jack that has been previously reworked in accordance with the incomplete CMM requirements.  This will restore the reliability of the Ejection Jack of the RAT.

James Coyne
Delegate of the Civil Aviation Safety Authority

28 November 2008