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/JBK 117/6 Amdt 4 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.
Kawasaki BK 117 Series Helicopters

AD/JBK 117/6 Amdt 5
Main Rotor Blade
11/2007
 
Applicability:
Model BK117, BK117A-3, BK117A-4, BK117B-1, BK117B-2, and BK117C-1 helicopters; all main rotor blade part numbers, except P/N 117-151511 and P/N
117-151521.

Requirement:
1.    Revise the KHI-BK117 Maintenance Manual to Revision No. 14 (or later approved revision) for Models KHI-BK117, BK117A-3, BK117A-4, BK117B-1, BK117B-2, and Revision No. 2 (or later approved revision) for Model
KHI-BK117C-1.
2.    Perform the inspection in accordance with the inspection interval and method specified in the KHI-BK117 Maintenance Manual, revised by Requirement 1.
If the inspection results exceed the allowable limit specified in the KHI-BK117 Maintenance Manual, before further flight, contact KHI Customer Service for technical advice.
Note 1:  Kawasaki Service Bulletin No. KSB-117-115A refers.
Note 2:  JCAB AD TCD-4114A-2006 refers.

Compliance:
Initially, before further flight after 28 March 2006.  Thereafter as specified in Requirement 2.

 
This Amendment becomes effective on 25 October 2007.

Background:
In response to incidents, the manufacturer recommended an immediate inspection for bulging on the upper and lower surfaces of the main rotor blades in the area of the outboard lead balance weight.
Amendment 1 referenced the JCAB AD and the Kawasaki service bulletin rather than the LBA AD and the MBB service bulletin of the initial issue.
Amendment 2 introduced an additional blade part number to applicability.
Amendment 3 was issued in response to a new JCAB AD, which expands applicability to all main rotor blade part numbers.

 
 
Amendment 4 was issued in response to a new JCAB AD, which transferred the inspection requirements of this Directive to the KHI-BK117 Maintenance Manual.  This also introduced an additional inspection.
Amendment 5 is issued to exclude certain Main Rotor Blade part numbers from inspection in accordance with this Airworthiness Directive.  There is no change to the requirements or compliance.
The original issue of this Airworthiness Directive became effective on 13 October 1994.

David Villiers
Delegate of the Civil Aviation Safety Authority
7 September 2007