Commonwealth legislation

AD/HU 369/51 Amdt 3 - Rotor Brake and Tail Rotor Drive Shaft Coupling

In ForceCTH

Jurisdiction

Commonwealth

Collection

legislative instrument

Plain English Summary

5/10 complexity

This airworthiness directive requires certain McDonnell Douglas (Hughes)/Kawasaki 369 helicopters to have the rotor brake de‑activated and the forward and rear flexible couplings inspected, unless the helicopter already has specified fail‑safe or modification work. It responds to reported fatigue failures of coupling components and sets deadlines: de‑activate within 25 flight hours and inspect within 100 hours and at each new Maintenance Release. Rotor brakes may be re‑activated after fitment of the approved fail‑safe coupling device.

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Current sections

Direct links to the current provisions in AD/HU 369/51 Amdt 3 - Rotor Brake and Tail Rotor Drive Shaft Coupling.

AD/HU 369/51 Amdt 3 - Rotor Brake and Tail Rotor Drive Shaft Coupling

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

SCHEDULE OF AIRWORTHINESS DIRECTIVES

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McDonnell Douglas (Hughes) and Kawasaki 369 Series Helicopters

AD/HU 369/51

Amdt 3

Rotor Brake and Tail Rotor Drive Shaft Coupling 1/87

Applicability: 1. Model 369D Series Helicopters equipped with a rotor brake system P/N 369H90123, not modified in accordance with S.I.N. DN-95 (installation of fail- safe coupling);

All model 369 Helicopters not modified in accordance with Service Information Notice DN-95, HN-173, DN-143, HN-206 or EN-31 as applicable.

Requirement: 1. De-activate the rotor brake system in accordance with Part I of Hughes S.I.N. DN-94.

Note: FAA AD 81-17-02 refers.

Inspect the forward and rear flexible couplings (P/Nos. 369H92564 and/or 369A5501) in accordance with Part II of S.I.N. DN-94.

Compliance: 1. Within 25 hours time in service after 26 October 1981.

Inspect within 100 hours time in service after 31 August 1986 and thereafter at each issue of a new Maintenance Release.

Note: Rotor brake may be re-activated after installation of coupling fail safe device in accordance with S.I.N. DN-95.

Background: In the past, there have been reports of several fatigue failures of forward flexible couplings on helicopters equipped with a rotor brake system. A recent investigation after an accident has revealed the possibility of either forward or rear couplings failing. Amdt 2 was issued to include both couplings, on all model 369 helicopters, for inspection. This amendment excludes helicopters amended to the requirement of AD/HU 369/68.

Source text

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

1 AD/HU 369/51 Amdt 3 - Rotor Brake and Tail Rotor Drive Shaft Coupling