AD/BO 105/23 Main Rotor Blade Secondary Bolt Locking (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 105/23 Main Rotor Blade Secondary Bolt Locking 10/2007

Applicability:

All Messerschmitt-Bolkow Blohm (MBB) Model BO 105 helicopters.

Requirement:

Action in accordance with the requirements of Transport Canada AD CF-88-18.

Note:  MBB ASB-BO-105-10-101 Revision 3 refers.

Compliance:

Unless already accomplished, before 27 October 2007.

This Airworthiness Directive becomes effective on 27 September 2007.

Background:

German LBA AD 87-106/2 mandated the use of lockwire as an anti-rotational lock for the secondary bolt of the main rotor blade.  MBB later devised a lockwasher as a more suitable anti-rotational device.

David Villiers
Delegate of the Civil Aviation Safety Authority

13 August 2007