AD/A320/202 Main Landing Gear Door Actuator (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/A320/202 Main Landing Gear Door Actuator 3/2007

Applicability:

Airbus A318, A319, A320 and A321 model aircraft.

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 at original issue.

2.    Repeat the inspection as described in Requirement 1.

Note:  EASA Airworthiness Directive No. 2006-0112 dated 15 May 2006 refers.

Compliance:

1.    Unless already accomplished, before the MLG door actuator has accumulated 3,000 flight cycles since new or within the next 800 flight cycles after the effective date of this AD, whichever occurs later.

If the number of flight cycles accumulated by MLG door actuator since new are not known, comply with Requirement 1 within the next 800 flight cycles after the effective date of this AD.

2.    At intervals not exceeding 900 flight cycles.

This Airworthiness Directive becomes effective on 15 March 2007.

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 AD mandates repetitive inspection of the opening sequence of the MLG door in order to identify the defective actuator(s).

James Coyne
Delegate of the Civil Aviation Safety Authority

2 February 2007