AD/A320/202 Amdt 1 Main Landing Gear Door Actuator (Cth)

AIRWORTHINESS DIRECTIVE

On the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/A320/202 and issues the following 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/A320/202 Amdt 1 Main Landing Gear Door Actuator 1/2009

Applicability:

AIRBUS A318-111, A318-112, A318-121, A318-122, A319-111, A319-112,
A319-113, A319-114, A319-115, A319-131, A319-132, A319-133, A320-111,
A320-211, A320-212, A320-214, A320-215, A320-216, A320-231, A320-232,
A320-233, A321-111, A321-112, A321-131, A321-211, A321-212, A321-213,
A321-231 and A321-232 aircraft models, all serial numbers, except those on which Airbus modification 38274 has been embodied in production or AIRBUS Service Bulletin (SB) A320-32-1338 has been embodied in service.

Requirement:

1.    Check the opening sequence of the door of the main landing gear (MLG) and apply associated corrective actions, if necessary, in accordance with the instructions of Airbus Service Bulletin (SB) A320-32-1309 original issue.

2.    Repeat the inspection as described in Requirement 1.

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

Terminating Action

Modification 38274 / SB A320-32-1338 introduces a MLG door actuator incorporating an improved retaining ring, located on the piston rod's extension end, and a new piston rod with machined shoulder to accommodate the thicker section of the modified retaining ring.

Embodiment of modification 38274 in production or SB A320-32-1338 in service constitutes an acceptable terminating action for the repetitive inspections required by Requirement 2 of this AD.

Note:  EASA Airworthiness Directive No. 2006-0112R1 dated 17 October 2008 refers.

Compliance:

1.    Remains unchanged as detailed in the original issue of this AD as:

Unless already accomplished, before the MLG door actuator has accumulated 3,000 flight cycles since new or within the next 800 flight cycles after
15 March 2007, whichever occurs later.

If the number of flight cycles accumulated by MLG door actuator since new is not known, comply with Requirement 1 within the next 800 flight cycles after
15 March 2007.

2.    At intervals not exceeding 900 flight cycles.

This Amendment becomes effective on 15 January 2009.

Background:

Some operators have reported slow operation of the MLG door opening/closing sequence and the resultant ECAM warnings.

On investigations, deterioration of the damping ring and associated retaining ring of the MLG door actuator and resultant debris was found to be the causal factor.  The debris may increase the friction inside the actuator, slowing down the opening or closing sequence of the MLG door.

During freefall operation, a MLG door that opens too slowly could interfere with the MLG wheel and may result in non-extension of the MLG.

This amendment has incorporated a terminating action to the repetitive inspection detailed in Requirement 2 of this AD.

James Coyne
Delegate of the Civil Aviation Safety Authority

28 November 2008