AD/EC 120/13 Amdt 1 Pilot's Cyclic Stick Friction Washers (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/EC 120/13 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 EC 120 Series Helicopters

AD/EC 120/13 Amdt 1 Pilot's Cyclic Stick Friction Washers 2/2006

Applicability:

Model EC 120 B helicopters, with serial numbers up to and including 1385, and fitted with:

-      thrust washer part number C671A1006201, of the pilot’s cyclic stick friction device,

-      pilot’s cyclic sticks, part numbers C671A1007101, C671A1007102, and C671A1003102.

Requirement:

1.    For helicopters equipped with pilot cyclic stick part numbers C671A1007101 or C671A1007102:

a.     Flights without friction applied to the pilot’s cyclic stick are prohibited.

b.    Remove the pilot’s cyclic stick and replace the thrust washers in accordance with paragraph 2 of Eurocopter EC 120 Alert Service Bulletin (ASB) No. 67A011.

Note 1:  DGAC AD F-2004-059 refers.

2.    For helicopters equipped with pilot cyclic stick part number C671A1003102:

a.     Flights without friction applied to the pilot’s cyclic stick are prohibited.

b.    Action in accordance with paragraphs 2.B. and 2.C. of ASB 67A011 Revision 1.

Before installing a cyclic stick held as spares, replace the stock of thrust washers held in store, and modify the pilot cyclic sticks in accordance with paragraph 2.B.5. of ASB No. 67A011 Revision 1.

Note 2:  DGAC AD F-2005-175 refers.

Compliance:

1.a. During each flight after 5 May 2004 until Requirement 1.b. is accomplished.

1.b. Within 550 flight hours or 6 months after 5 May 2004, whichever occurs first.

2.a. During each flight after 16 February 2006 until Requirement 2.b. is accomplished.

2.b. Before 28 February 2006, unless already accomplished.

The compliance times for Requirement 1 remain unchanged by this issue.

This Amendment becomes effective on 16 February 2006.

Background:

A report was received of sudden restriction of cyclic stick travel on an EC 120 B helicopter during a flight when the cyclic stick was moved back to neutral.

Amendment 1 is issued in response to a new DGAC AD, which introduces a revision of the Requirement document, and a new cyclic stick part number.

David Villiers
Delegate of the Civil Aviation Safety Authority

21 December 2005