COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Bell Helicopter Textron Canada (BHTC) 206 and Agusta Bell 206 Series Helicopters
AD/BELL 206/103 Tension/Torsion Strap Fitting 8/86
Applicability: All Bell 206B III Series Helicopters fitted with tension/torsion strap sleeve fitting P/No. 206-011-150-101.
Requirement: For aircraft which have had the tension/torsion strap assembly disassembled since new, inspect the strap fitting (P/No 206-011- 150-101) to static stop (P/N. 206-011- 121-103) alignment. The strap fitting (P/No. 206-011-150-101) has 3 flats adjacent to each other: the centre and smallest is the correct flat for mating with the static stop.
Note: With the blade grip in the zero pitch position, the wrong flat aligns with the stop, thus positioning the T/T strap so that it increases twist with pitch increase instead of vice versa.
Compliance: Inspect within 100 hours time in service after 31 August 1986 and thereafter anytime the tension/torsion strap assembly is disassembled until P/No. 206-011-150-101 fitting is replaced with P/No. 206-011-150-105 fitting.
Background: If the strap fitting P/NO. 206-011-150-101 is refitted incorrectly and should the aircraft suffer an engine failure, full collective pitch cannot be achieved.
The strap fitting P/No. 206-011-150-101 is fitted by the manufacturer and is not available as a replacement part: P/No. 206-011-150-105 is supplied. The problem does not occur when the latter Part Number is fitted.