Commonwealth legislation

AD/BELL 212/25 Amdt 4 - Main Rotor Yoke

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Jurisdiction

Commonwealth

Collection

legislative instrument

Plain English Summary

4/10 complexity

This airworthiness directive requires Bell 212 helicopters fitted with main rotor yoke P/N 204-011-102-* to be inspected in situ under Bell Alert SB 212-90-60 and, at specified intervals, removed and inspected per FAA AD 79-20-05; it also adds a yoke spindle inspection at 1,200 hours / 24 months (Requirement; Background). The stated aim is to detect fatigue cracks; mechanically it increases recurring inspection duties, maintenance time, downtime and record-keeping for operators, while allowing earlier inspections to be credited.

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Current sections

Direct links to the current provisions in AD/BELL 212/25 Amdt 4 - Main Rotor Yoke.

AD/BELL 212/25 Amdt 4 - 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 212/25

Amdt 4

Main Rotor Yoke 9/91

Applicability: All helicopters fitted with main rotor yoke P/N 204-011-102- (all dash numbers).

Requirement: 1. Inspect the main rotor yoke in-situ in accordance with the Accomplishment Instructions in Bell Alert SB No 212-90-60, Revision A, dated 31 August 1990.

Remove the yoke assembly from the main rotor hub assembly and inspect the yoke in accordance with FAA AD 79-20-05, Amendment 39-3662.

Compliance: As detailed in the Requirement Documents.

Background: Amendment 3 implemented the additional inspections of ASB 212-87-48, which was issued as a result of fatigue cracks being found in service. It required that visual inspections of the main rotor yoke be performed daily and every 1200 hours/24 months. These are additional to the more detailed 2400 hourly inspection specified in FAA AD 79-20-05.

Amendment 4 specifies Bell Alert SB 212-90-60, which supersedes ASB 212-87-48, and adds a yoke spindle inspection to Part III, required at 1200 hours/24 month intervals. Inspections done to earlier amendments may be considered for the purposes of determining when amendment 4 inspections are due.

Source text

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

1 AD/BELL 212/25 Amdt 4 - Main Rotor Yoke