AD/AS 355/97 Rotor Flight Control Collective Lever Recess (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.

Eurocopter AS 355 (Twin Ecureuil) Series Helicopters

AD/AS 355/97 Rotor Flight Control - Collective Lever Recess 3/2008

Applicability:

Eurocopter AS 355 helicopters: Models AS 355 E, AS 355 F, AS 355 F1 and AS 355 F2, all pre MOD 071995.

Requirement:

1.    Modify the collective lever in accordance with instructions detailed in paragraph 2.B. of EUROCOPTER Alert Service Bulletin (ASB) No. 67.00.12 Revision 2 or later approved revison.

2.    Do not install covers P/N 355A27-2373-20 on any AS 355 series helicopter.

Note:  EASA AD 2007-0289 dated 19 November 2007 refers.

Compliance:

1.    Within the next 550 Flight Hours or 12 months, after the effective date of this AD, whichever occurs first, unless previously accomplished.

2.    From the effective date of this AD.

This Airworthiness Directive becomes effective on 13 March 2008.

Background:

EASA have advised of a collective lever jamming, which occurred on an AS 350 helicopter on taking-off.  This incident was caused by a foreign object which had penetrated inside the upper recess of the slide and made the collective lever jam.  The actions specified by this AD are intended to prevent any further travel restriction caused by foreign objects, which can cause loss of collective pitch control, and subsequent loss of control of the helicopter.

Charles Lenarcic
Delegate of the Civil Aviation Safety Authority

21 January 2008