AD/BELL 412/43 - Tail Rotor Counterweight Bellcrank Retention Nut (Cth)

COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES

Bell Helicopter Textron 412 Series Helicopters

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.

AD/BELL 412/43 Tail Rotor Counterweight Bellcrank Retention Nut

Applicability: Model 412, 412EP, and 412CF helicopters. Requirement: 1. For Model 412 or 412EP helicopters:

9/2001 DM 1. Remove the two existing retention nuts retaining the bellcranks, part number 212-011-705-001, and install retention nuts, part number MS14145L6 or MS17826-6, in accordance with paragraphs (1) through (5) of the Accomplishment Instructions in Bell Helicopter Textron Alert Service Bulletin (ASB) 412-00-102 Revision A, dated 13 September 2000. A used nut must not be installed.

b. Inspect the retention nuts and corrosion preventive compound (CPC) coating in accordance with paragraph (6) of the Accomplishment Instructions in ASB 412-00-102 Revision A. Reapply the CPC coating if deficiencies are found in the coverage and protection of the area. Replace any retention nut found with any corrosion, mechanical damage, a crack, or looseness, with a serviceable new retention nut before further flight.