AD/HU 369/109 - Tail Rotor Gearbox Attachment (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 CAR 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.

McDonnell Douglas (Hughes) and Kawasaki 369 Series Helicopters

AD/HU 369/109 Tail Rotor Gearbox Attachment 10/2002

Applicability: MD Helicopters Inc. Model 369D, 369E, 369F, and 369FF helicopters, modified in accordance with Aerometals Supplemental Type Certificate (STC) SH5055NM or SH4801NM.

Requirement: 1. Initial Inspection and bolt replacement:

1. Carry out an inspection of the tail rotor gearbox attachment bolts to determine the part number.

b. If the part number cannot be determined or if the bolt is not P/N NAS1304- 26, replace the bolt with bolt, P/N NAS1304-26.

c. Torque the bolt to 100-110 in- lbs and apply slippage mark.

d. Remove the tailboom control rod and determine the number of threads protruding from each nutplate on the internal surface of the aft tailboom frame casing, P/N 369D23503, as shown in Figure 1 of this Directive. At least one thread must protrude. If more than four threads protrude, add an additional washer, P/N AN960D416, under the bolt head.

e. Torque the bolt to 100-110 in- lbs and re apply slippage mark.

2. Repetitive Inspection: