Commonwealth legislation

AD/BELL 212/53 - Main Rotor Yoke

RepealedCTH

This Act has been repealed and is no longer in force. It is retained for historical reference.

Jurisdiction

Commonwealth

Collection

legislative instrument

Plain English Summary

2/10 complexity

This rule requires operators of Bell 212 helicopters to perform recurring mandatory inspections of main rotor yokes (part 204-011-102) for corrosion and cracking using magnetic particle inspection, focusing on the pillow block bushing holes. Initial inspection is due by 1,200 flight hours or within 100 hours after 2 Feb 1995, then every 1,200 hours; damaged or cracked yokes must be repaired within limits or replaced before flight.

It matters because twelve cracks were found and yoke failure could cause catastrophic loss of the main rotor and loss of control.

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Current sections

Direct links to the current provisions in AD/BELL 212/53 - Main Rotor Yoke.

AD/BELL 212/53 - Main Rotor Yoke

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 212 Series Helicopters

AD/BELL 212/53 Main Rotor Yoke 2/95

Applicability: All Bell 212 model helicopters with Main Rotor Yokes P/N 204-011-102 (all dash numbers) installed.

Requirement: 1. Remove Main Rotor Yoke from the hub assembly. Visually inspect the pillow block bushing holes for corrosion and mechanical damage. Inspect the yoke for cracks in accordance with the BTHI component repair and overhaul manual, using the magnetic particle method.

Rework damaged yokes in accordance with the limits of the BTHI component repair and overhaul manual. Remove from service cracked components and components that cannot be reworked within those limits.

Note: FAA AD 93-05-01 refers.

Compliance: 1. Inspect in accordance with Requirement 1 before 1200 hours time in service or within 100 hours time in service after 2 February 1995, whichever occurs later. Re-inspect in accordance with requirement 1 at intervals not to exceed 1200 hours time in service.

Rework damaged yokes in accordance with Requirement 2 before further flight.

Background: There have been 12 cracks reported in the main rotor yoke pillow block bushing holes. This AD is intended to detect corrosion and cracking from corrosion pits in the main rotor yoke assembly which could result in failure of the main rotor system and loss of control of the helicopter.

Source text

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

1 AD/BELL 212/53 - Main Rotor Yoke

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

SCHEDULE OF AIRWORTHINESS DIRECTIVES

Bell Helicopter Textron 212 Series Helicopters

AD/BELL 212/53 Main Rotor Yoke 2/95

Applicability: All Bell 212 model helicopters with Main Rotor Yokes P/N 204-011-102 (all dash numbers) installed.

Rework damaged yokes in accordance with the limits of the BTHI component repair and overhaul manual. Remove from service cracked components and components that cannot be reworked within those limits.

Note: FAA AD 93-05-01 refers.

Rework damaged yokes in accordance with Requirement 2 before further flight.