Commonwealth legislation

AD/BELL 206/135 - Main Rotor Trunnion and Mast

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Commonwealth

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legislative instrument

Plain English Summary

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This airworthiness directive requires operators of specified Bell 206L-series helicopters to retire certain main rotor trunnions and masts at set Retirement Index Numbers (RINs) or by specified service times, and bans trunnion P/N 206-011-120-001 from further use. It replaces hour-based life limits with a power-change‑event (RIN) basis and requires a history card for each component to record RINs. Operators must track RINs per Bell ASB 206L-94-99 Revision A and remove parts by the stated deadlines; CASA enforces compliance.

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AD/BELL 206/135 - Main Rotor Trunnion and Mast

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

SCHEDULE OF AIRWORTHINESS DIRECTIVES

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Bell Helicopter Textron Canada (BHTC) 206 and Agusta Bell 206 Series Helicopters

AD/BELL 206/135 Main Rotor Trunnion and Mast 10/95

Applicability: All Bell 206L, 206L-1, 206L-3 and 206L-4 helicopters fitted with main rotor trunnion P/N 206-011-120-103 and mast P/N 206-040-535-001/-005/-101 /-105.

Note: Main rotor trunnion P/N 206-011-120-001 is no longer permitted to remain in service.

Requirement: Retire the main rotor trunnion before it has attained a Retirement Index Number (RIN) of 24 000 as adjusted in Bell ASB 206L-94-99, Revision A, Table 3.

Retire the mast before it has attained a RIN of 44 000 as adjusted in Table 4, or before the time in service as adjusted in Table 2 of Bell ASB 206L-94-99, Revision A, whichever occurs first.

Compliance: Before 100 hours time in service after 14 September 1995 but no later than 17 December 1995.

Background: Bell Helicopter’s fatigue testing and analysis have shown that the life of certain critical components can be estimated in a more accurate manner when the calculations are based on changes in power. The fatigue life is no longer to be based on component hours but on the number of power change events. A history card for each component will have to be created to document the Retirement Index Number.

Source text

Sourced from the Federal Register of Legislation (legislation.gov.au), CC BY 4.0.

1 AD/BELL 206/135 - Main Rotor Trunnion and Mast