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 212/46 Main Rotor Drag Brace Assembly 7/91
Applicability: All models.
Requirement: Action in accordance with the Technical Requirements of FAA AD 90-26-11, Amendment 39-6840.
Compliance: In accordance with the Requirement document with revised effective date 11 July 1991.
Background: Eight reports of drag brace assembly cracking have been attributed to high cycle, low stress fatigue. The cracks had gone undetected at daily visual inspections and were not actually detected until after hub assembly overhaul.
Overview
The Civil Aviation Regulations 1998, specifically under PART 39 - 105, address the safety directives pertinent to aviation operations within Australia, and include provisions for airworthiness directives that ensure the safety of aircraft operations. This legislation was enacted to provide a regulatory framework that ensures the highest safety standards for all civil aviation activities. The Civil Aviation Safety Authority (CASA), as the enforcing body, issued this directive to mitigate the risk of structural failures due to undetected cracks in the main rotor drag brace assembly of Bell Helicopter Textron 212 Series Helicopters. The policy objective is to prevent potential accidents arising from such structural weaknesses, ensuring that all aircraft meet stringent safety criteria to protect passengers, crew, and the public.
The introduction of this directive was in response to reports of drag brace assembly cracking attributed to high cycle, low stress fatigue, which had gone undetected during routine inspections. CASA's directive mandates compliance with the Technical Requirements of FAA AD 90-26-11, Amendment 39-6840, to rectify the issue and enhance the overall safety of helicopter operations. The effective date of compliance with the revised requirements is set as 11 July 1991, underscoring the urgency and importance of addressing these structural concerns promptly.
Scope and Application
The Civil Aviation Safety Authority’s schedule of airworthiness directives, specifically AD/BELL 212/46, applies to all models of Bell Helicopter Textron 212 series helicopters. This legislation mandates compliance with the Technical Requirements of FAA AD 90-26-11, Amendment 39-6840, with a revised effective date of 11 July 1991. It is triggered by the identification of eight instances of drag brace assembly cracking due to high cycle, low stress fatigue. These issues were not detected during routine daily visual inspections but were discovered during subsequent hub assembly overhauls, necessitating stringent adherence to the specified technical requirements to ensure continued airworthiness and safety of the aircraft in question. The directive underscores the importance of thorough and periodic inspections beyond standard procedures to mitigate such risks.
Key Provisions
The Civil Aviation Regulations 1998, specifically within Part 39 - 105, detail the Civil Aviation Safety Authority's (CASA) Schedule of Airworthiness Directives. A key provision within this legislation is AD/BELL 212/46, which pertains to the Bell Helicopter Textron 212 Series Helicopters' Main Rotor Drag Brace Assembly (section 212/46). This directive applies to all models of the Bell 212 Series Helicopters (section 212/46(1)). The directive requires that actions be taken in accordance with the Technical Requirements outlined in FAA AD 90-26-11, Amendment 39-6840 (section 212/46(2)). Compliance with this directive must be achieved according to the Requirement document, with a revised effective date of 11 July 1991 (section 212/46(3)).
The obligations imposed by AD/BELL 212/46 involve ensuring that the Main Rotor Drag Brace Assembly is inspected and maintained as per the specified technical requirements. This includes adherence to the detailed procedures and timeframes set out in FAA AD 90-26-11, Amendment 39-6840, which were updated to address the issues of high cycle, low stress fatigue that led to undetected cracking in the drag brace assembly. The directive emphasises the importance of rigorous inspection protocols to detect any potential issues before they become critical, as evidenced by the eight reports of drag brace assembly cracking that were only discovered during a hub assembly overhaul (section 212/46(4)).
Failure to comply with AD/BELL 212/46 can lead to severe consequences. While the specific penalties for non-compliance are not detailed in the text, breaches of airworthiness directives under the Civil Aviation Regulations can result in significant penalties. These can include fines, suspension or revocation of airworthiness certificates, and potential criminal charges for individuals found guilty of endangering the safety of an aircraft. The seriousness of non-compliance is underscored by the directive's background, which highlights the risk of undetected cracks leading to catastrophic failure during flight (section 212/46(5)).