AD/GBK 117/15 Main Rotor Blades with Bolted Lead Inner Weights (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 BK 117 Series Helicopters

AD/GBK 117/15 Main Rotor Blades with Bolted
Lead Inner Weights 6/2005 DM

Applicability:

Models BK117 A-1 through C-1, all serial numbers.

Requirement:

Action in accordance with Eurocopter Deutschland Alert Service Bulletin No. ASB-MBB-BK117-10-125, dated 14 February 2005, or later EASA approved revision.

Note:  LBA AD D-2005-115 refers.

Compliance:

As specified in the Requirement document.  Unless it has already been accomplished, the 4 week period for the log check begins on 20 April 2005.

This Airworthiness Directive becomes effective on 20 April 2005.

Background:

The LBA received a report of severe vibrations in-flight on a BK117 helicopter.  The pilot immediately performed a safe landing, and the initial inspection revealed a cracked-open main rotor blade trailing edge.  A subsequent inspection by the manufacturer revealed that a part of a bolted lead inner weight had come loose.  This Directive introduces a life limit for blades with bolted lead inner weights installed.

David Villiers
Delegate of the Civil Aviation Safety Authority

14 April 2005