AD/BO 105/27 Cyclic-Stick Locking Device (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 BO 105 Series Helicopters

AD/BO 105/27 Cyclic-Stick Locking Device 6/2009

Applicability:

Eurocopter Deutschland GmbH (ECD) , BO 105 A, BO 105 C, BO 105 LS A-1,
BO 105 D, BO 105 DS, BO 105 DB, BO 105 DBS, BO 105 DB-4, BO 105 DBS-4, BO 105 DBS-5 and BO 105 S helicopters.

Requirement:

1.    Modify the cyclic stick locking/centring device by removing the spring from the cyclic stick lock in accordance with ECD Alert Service Bulletin (ASB) ASB BO105-40-106 dated 19 December 2008.

2.    Amend the Rotorcraft Flight Manual (FLM) by inserting the following note:

“NOTE: Move cyclic stick in its neutral position before the engines are started. The neutral position and the centring of the cyclic stick can be achieved by folding down the holder assy. Locking of the cyclic stick is no longer possible.”

This may be accomplished by inserting a copy of this AD into the FLM, or by FLM page(s) supplied by ECD.

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

Note:  EASA AD 2009-0079 dated 1 April 2009 refers.

Compliance:

For Requirement 1 - Within 6 months after the effective date of this AD.

For Requirement 2 - Concurrent with the modification as detailed in Requirement 1 of this AD.

This Airworthiness Directive becomes effective on 4 June 2009.

Background:

There have been several cases reported where take-off was executed with a locked cyclic stick on EC135 series helicopters.  The Stick Locking Device as installed on BO 105 rotorcraft types has a similar function.  Trying to take off with a locked cyclic stick may lead to loss of control of the helicopter.

Although no recent reports of take-off with a locked cyclic stick have been received concerning BO 105 helicopters, to prevent such occurrences, Eurocopter Deutschland (ECD) has developed a modification of the cyclic stick cantilever.  After modification, locking of the cyclic stick is no longer possible.  The cyclic stick can only be centred in its neutral position.

This AD requires the modification of the cyclic stick locking/centring device and the amendment of the applicable (FLM).

James Coyne
Delegate of the Civil Aviation Safety Authority

17 April 2009