Federal Register of Legislation - Australian Government

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AD/ECUREUIL/120 Amdt 1 Airworthiness Directives/Pt 105 — Aircraft as made
Engine Controls - Twist Grip Assembly
Administered by: Infrastructure and Transport
Exempt from sunsetting by the Legislative Instruments Act 2003 s 54(2) item 9
Registered 21 Mar 2007
Tabling HistoryDate
Tabled HR25-Mar-2007
Tabled Senate25-Mar-2007
Date of repeal 17 Sep 2013
Repealed by CASA ADCX 018/13 - Revocation of Airworthiness Directives

 

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/120 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/120 Amdt 1

Engine Controls - Twist Grip Assembly

5/2007 DM

 

Applicability:

AS 350 B3 helicopters, equipped with twist grips, before the embodiment of MOD 073261 (new twist grip assemblies compatible with the Arriel 2B1 engine installation).

Requirement:

1.    If not previously accomplished, adjust the ‘forced idle’ microswitch and check it for correct operation, in accordance with paragraph 2.B.2. and 2.B.3. of Eurocopter Alert Service Bulletin (ASB) 05.00.49 dated 1 February 2006, or later EASA approved revision.

 

2.    Accomplish a functional test of the of the ‘forced idle’ microswitch in accordance with paragraph 2.B.3. of ASB 05.00.49, or later EASA approved revision.

 

3.    Replace the ‘forced idle’ microswitch in accordance with paragraph 2.B.4. of ASB 05.00.49, or later EASA approved revision.

 

Note 1:  EASA AD 2006-0094 refers.

Compliance:

For Requirement 1 - Remains unchanged as ‘Within 110 hours time in service (TIS) after the effective date of the original issue of this Directive’.

 

For Requirement 2 - Within 110 hours TIS after the Requirement 1 check and thereafter at intervals not to exceed 110 hours TIS.

 

For Requirement 3:

 

Helicopters with less than 440 hours total TIS - Before the accumulation of 550 hours total TIS and thereafter at intervals not to exceed 550 hours TIS.

 

Note 2:  Helicopters with less that 440 hours total TIS at the effective date of this Directive may have to comply with the Requirement 2 functional check before the microswitch is required to be replaced.

 

Helicopters with 440 or more hours total TIS - Within 110 hours TIS after the effective date of the original issue of this Directive and thereafter at intervals not to exceed 550 hours TIS.

 

 

This Amendment becomes effective on 26 March 2007.

Background:

The European Aviation Safety Agency (EASA) has advised of an incident during an autorotation training procedure where the engine remained a idle rating although the twist grip had been turned back to the ‘FLIGHT’ position.

 

Analysis revealed that the ‘forced idle’ microswitch pin had jammed in the pushed-in position.  The jamming resulted in the engine speed being held at ‘forced idle’.

 

The original issue of this Directive required the initial adjustment and check of the microswitch, followed by repetitive inspections and replacement.

 

This Amendment changes the wording of the repetitive inspection requirements to remove an ambiguity in the compliance interval.  This Amendment is introduced following advice from industry.

 

The original issue of this Directive became effective on 26 July 2006.


Charles Lenarcic
Delegate of the Civil Aviation Safety Authority

16 March 2007