COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Cessna 150, F150, 152 & F152 Series Aeroplanes
AD/CESSNA 150/2
Amdt 1
Main Undercarriage “U” Bolts 11/67
Applicability: All models fitted with “U” bolts P/N 0441161 types.
Requirement: 1. Visual: Inspect the main undercarriage “U” bolts P/N 0441161 in situ for cracks and other damage and check that the “U” bolt retaining nuts are torqued to the values specified in the Cessna Service Manual.
2. Magnetic Particle: Remove the main undercarriage “U” bolts P/N 0441161 and inspect by the magnetic particle method for cracks particularly in the radius of the bends and in the root of the threads.
Compliance: Visual: At intervals not exceeding 100 hours time in service.
Magnetic Particle: At intervals not exceeding 500 hours time in service.
Overview
The Civil Aviation Regulations 1998, enacted by the Parliament of the Commonwealth of Australia, were designed to address the need for a comprehensive regulatory framework governing all aspects of civil aviation within Australia. This legislation, specifically under PART 39, aims to ensure the safety and efficiency of civil aviation operations by establishing stringent standards and procedures, including the issuance of airworthiness directives. One such directive pertains to the Cessna 150, F150, 152 & F152 series aeroplanes, focusing on the main undercarriage “U” bolts. This directive was introduced to mitigate risks associated with the structural integrity of these bolts, ensuring they are periodically inspected and maintained to prevent failures that could compromise flight safety. The underlying policy objective is to uphold the highest standards of aviation safety through meticulous oversight and regular inspections of critical components.
Scope and Application
The Civil Aviation Regulations 1998, specifically PART 39 - 105, apply to all Cessna 150, F150, 152, and F152 series aeroplanes equipped with "U" bolts part number 0441161. These regulations mandate certain safety directives aimed at ensuring the airworthiness of the aircraft by focusing on the inspection and maintenance of the main undercarriage "U" bolts. The inspection must be conducted visually to check for cracks and other forms of damage while ensuring the "U" bolt retaining nuts are torqued to the specified values as outlined in the Cessna Service Manual. Additionally, a magnetic particle inspection must be performed to detect cracks, particularly in the bends and thread roots, of these bolts. Compliance with these regulations requires that visual inspections be conducted at intervals not exceeding 100 hours of time in service, and magnetic particle inspections at intervals not exceeding 500 hours of time in service. The scope of these regulations is national, applying across the Commonwealth of Australia, and their implementation is overseen by the Civil Aviation Safety Authority.
Key Provisions
The Civil Aviation Regulations 1998, under Part 39 - 105, address the airworthiness directives for specific models of Cessna aeroplanes. For the Cessna 150, F150, 152, and F152 series, there is a specific Airworthiness Directive (AD) concerning the main undercarriage “U” bolts, identified by part number 0441161 (AD/CESSNA 150/2 Amdt 1). This directive applies to all models fitted with these particular “U” bolts. The directive mandates that these bolts be inspected for cracks and other damage, and it requires that the “U” bolt retaining nuts are torqued to the values specified in the Cessna Service Manual.
The inspection requirements under this directive are twofold. Firstly, a visual inspection (section 1(1)) must be conducted in situ to check for any visible cracks or damage to the main undercarriage “U” bolts. Additionally, the retaining nuts must be confirmed to be torqued correctly. Secondly, a magnetic particle inspection (section 1(2)) is required, which involves removing the “U” bolts and inspecting them for cracks, especially in the bend radius and at the thread roots, using the magnetic particle method.
Compliance with these inspection intervals is critical to ensure the airworthiness of the aircraft. The visual inspection must be performed at intervals not exceeding 100 hours of time in service (section 1(1)), ensuring that any visible damage is detected and addressed promptly. The magnetic particle inspection must occur at intervals not exceeding 500 hours of time in service (section 1(2)), providing a more comprehensive check for hidden defects that might not be visible during a standard visual inspection.
Failure to adhere to these inspection requirements can result in serious safety risks. The regulations do not explicitly state penalties for non-compliance within this section, but any breach of airworthiness directives can lead to enforcement actions by the Civil Aviation Safety Authority (CASA). Such actions may include the grounding of the aircraft, fines, and potential criminal charges if the non-compliance results in an aviation accident or incident. Operators must, therefore, strictly follow these directives to avoid any adverse consequences and ensure the safety and compliance of their operations.