Commonwealth legislation

AD/HU 369/71 - Tail Rotor Transmission Mounting Studs

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Jurisdiction

Commonwealth

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legislative instrument

Plain English Summary

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This airworthiness directive requires inspections and corrective action on tail-rotor transmission mounting studs for all McDonnell Douglas (Hughes) and Kawasaki 369D/E/F/FF helicopters, following McDonnell Douglas Service Instructions DN-151/EN-39/FN-28 because studs have failed and nut torque loss was reported (Background). Operators must do an initial action before the next flight (Part 1), pilots must perform and can certify preflight checks each flight (Part 2; Note), repairs are mandatory within 25 flight hours or by 20 Nov 1987 (Part 3), and maintenance releases updated (Part 4). Operators bear repair and compliance costs; pilots and maintenance staff decide, perform and record the inspections and repairs (Parts 1–4, Note).

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Current sections

Direct links to the current provisions in AD/HU 369/71 - Tail Rotor Transmission Mounting Studs.

AD/HU 369/71 - Tail Rotor Transmission Mounting Studs

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 369/71 Tail Rotor Transmission Mounting Studs 13/87

TLX

Applicability: All model 369D, 369E, 369F and 369FF series helicopters.

Requirement: Action in accordance with McDonnell Douglas SIN No DN-151, EN-39, FN-28, as applicable.

Compliance: Part 1 of Requirement document - unless already accomplished, prior to next flight.

Part 2 of Requirement document - during each pilot’s preflight inspection.

Part 3 of Requirement document - unless already accomplished, within 25 hours time in service or by 20 November 1987 whichever occurs first.

Part 4 of Requirement document - prior to each issue or a new Maintenance Release after 20 November 1987.

Note: The Part 2 inspection may be accomplished by the pilot in command in which case he shall enter and certify for this AD in Col 2 Part 3 of the Maintenance Release on each occasion.

Background: There have been several reported instances where some or all tail rotor transmission mounting studs have failed with indications of bending fatigue. Also, movement between the T/R gearbox and mounting bracket has occurred due to loss of mounting stud nut torque.

Source text

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

1 AD/HU 369/71 - Tail Rotor Transmission Mounting Studs