AD/GBK 117/14 - Tail Rotor Drive Bearings (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 39.1 (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 117/14 Tail Rotor Drive Bearings 13/2003

Applicability: MBB-BK117 helicopters models A-1 though C-1 inclusive and incorporating any of the following:

1. A tail rotor transmission part number (P/N) 4639003001 or 4639003007 with a serial number (S/N) 900 through 932 inclusive; or

b. An intermediate gearbox P/N 4639002001 or 4639002005 with a S/N 902 though 928 inclusive; or

c. A tail rotor transmission P/N 4639003001 or 4639003007 that had been overhauled or repaired in the period 16 July 2001 to 14 April 2003, the effective date of Eurocopter Alert Service Bulletin (ASB) MBB-BK117-30-108 Revision 1; or

d. An intermediate gearboxes that had been overhauled or repaired in the period 16 July 2001 to 14 April 2003, the effective date of Eurocopter ASB MBB-BK117- 30-108 Revision 1; or

e. The tail rotor transmission and/or the intermediate gearbox is fitted with a bearing P/N 4639310006, S/N 3246 through 3598 inclusive; and

f. The tail rotor transmission and/or the intermediate gearbox has not been inspected in accordance with Paragraph 2.B.2 of Eurocopter ASB MBB-BK117- 30-108 Revision 1.