AD/Ecureuil/119 Amdt 2 Engine Controls Twist Grip Assembly (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/ECUREUIL/119 Amdt 1 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.

Eurocopter AS 350 (Ecureuil) Series Helicopters

AD/ECUREUIL/119 Amdt 2 Engine Controls - Twist Grip Assembly 13/2008

Applicability:

EUROCOPTER EC 130 B4 helicopters, all serial numbers fitted with:

- twist grip assemblies part numbers (P/N) 350A27520900, 350A27520901, 350A27520902 or 350A27520903 on the pilot's side with serial numbers (S/N) below 64.

- twist grip assemblies P/N 350A27521201 on the co-pilot side with S/N below 11 and between 22 and 66 (inclusive).

- twist grip assemblies P/N 350A27521201 on the co-pilot side with S/N from 11 to 21 (inclusive) and no letter “V” on the lever base.

Requirement:

1.    Replace the drive tube in co-pilot twist grip assembly P/N 350A27521201 with S/N from 11 to 21 (inclusive) and no letter “V” on the lever base in accordance with paragraph 2.B. of EUROCOPTER EC 130 ASB No. 76A002.

2.    In autorotation training, the manoeuvre must be carried out until the helicopter touches down (full autorotation).

3.    Do not install a twist grip assembly P/N 350A27521201 with S/N from 11 to 21 (inclusive) and no letter “V” on the lever base on a helicopter, unless the drive tube has been replaced and the collective lever marked in accordance with paragraphs 2.B.2. and 2.B.3. of EUROCOPTER EC 130 ASB No. 76A002.

4.    Do not install twist grip assemblies P/N 350A27520900, 350A27520901, 350A27520902 and 350A27520903 with S/N below 64 on the pilot's side or twist grip assembly P/N 350A27521201 with S/N below 11 and between 22 and 66 (inclusive) on the co-pilot’s side, unless the bonding between the control pinion and the drive tube has been checked in accordance with paragraph 2.B.3. of EUROCOPTER EC 130 ASB No. 76A001 Revision 1 before installation on a helicopter.

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

Note:  EASA AD 2008-0184 dated 6 October 2008 refers.  This AD supersedes EASA AD 2006-0079.

Compliance:

For Requirement 1 - Within 110 flight hours or 9 months after the effective date of this AD, whichever occurs first, unless previously accomplished.

For Requirement 2 - Pending replacement of the twist grip drive tube as detailed in Requirement 1 of this AD.

For Requirement 3 - After the effective date of this AD.

For Requirement 4 - Before installation on a helicopter after the effective date of this AD.

This Amendment becomes effective on 18 December 2008.

Background:

This AD was issued following a case experienced during an autorotation training procedure during which the engine remained at idle rating although the twist grip had been turned back to the flight position.

Analysis has revealed failure of the twist grip drive tube and control pinion bonded attachment due to non-compliant surface preparation.

Amendment 1 corrected a typographical error in Requirement 3 of this AD.  The statement should have read “paragraph 2.B.3” instead of “paragraph 2.8.3”.  There were no changes to the compliance periods.

This amendment requires the replacement of certain twist grips and to check other twist grips before installation.

Amendment 1 of this AD became effective on 3 August 2006.

The original issue of this AD became effective on 6 July 2006.

James Coyne
Delegate of the Civil Aviation Safety Authority

6 November 2008