COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Piper PA-25 (Pawnee) Series Aeroplanes
AD/PA-25/7 Main Undercarriage Safety Cable - Installation 5/75
Applicability: All models.
Requirement: 1. Modify all aeroplanes by installing a safety cable between the main undercarriage vee assembly and the fuselage frame to prevent the collapse of the undercarriage in the event of the shock strut, or the shock strut AN-20 bolt, failure.
2. The cable shall pass around the two tubes of the vee assembly at the shock strut end and between the vee formed by the two top diagonal tubes of the fuselage frame.
3. The length of the cable shall allow full undercarriage deflection and provision shall be made to prevent tubes from becoming worn by the cable.
4. The minimum acceptable cable strength is 7,000 lb. Compliance: Within 100 hours time in service from 30 May 1975.
Overview
The Civil Aviation Regulations 1998, as amended by the legislative instrument F2006B05579, introduce specific airworthiness directives aimed at enhancing the safety of civil aviation. This legislation was enacted to address safety concerns related to the structural integrity of the main undercarriage of Piper PA-25 (Pawnee) Series Aeroplanes. The Australian Government, through the relevant legislature, introduced these regulations to ensure that aircraft meet the necessary safety standards to prevent undercarriage collapse, thereby protecting both passengers and crew. The policy objective behind these directives is to mandate modifications to aeroplanes, specifically the installation of a safety cable between the main undercarriage vee assembly and the fuselage frame, to mitigate the risk of undercarriage failure due to shock strut or bolt failure. This directive requires compliance within a specified timeframe to ensure that all affected aircraft are modified to meet the safety standards set forth in the regulations.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 105 and the Civil Aviation Safety Authority Schedule of Airworthiness Directives, applies to all models of Piper PA-25 (Pawnee) series aeroplanes. This legislation mandates the modification of these aeroplanes to install a safety cable between the main undercarriage vee assembly and the fuselage frame, thereby preventing the collapse of the undercarriage in the event of shock strut or shock strut AN-20 bolt failure. The directive specifies that the cable must pass around the two tubes of the vee assembly at the shock strut end and between the vee formed by the two top diagonal tubes of the fuselage frame. Additionally, the cable must allow full undercarriage deflection and measures must be taken to prevent tube wear. The minimum acceptable strength of the cable is set at 7,000 lb, with compliance required within 100 hours of time in service from 30 May 1975. This regulation is applicable across the Commonwealth of Australia and ensures compliance through the Civil Aviation Safety Authority, with no stated exclusions or exemptions within the scope of the directive.
Key Provisions
The main operative sections of the AD/PA-25/7 mandate the installation of a safety cable on Piper PA-25 (Pawnee) series aeroplanes to enhance safety by preventing undercarriage collapse in the event of shock strut failure (sections 1 to 4). Specifically, section 1 requires the installation of a safety cable between the main undercarriage vee assembly and the fuselage frame. Section 2 specifies the cable's routing around the tubes of the vee assembly and between the top diagonal tubes of the fuselage frame. Section 3 stipulates the cable's length must allow full undercarriage deflection and must not cause wear to the tubes. Finally, section 4 sets the minimum acceptable cable strength at 7,000 lb.
The obligations and requirements imposed by this directive on the parties governed by the Civil Aviation Regulations 1998 include ensuring compliance with the installation of the safety cable within 100 hours of the aeroplane's time in service from 30 May 1975. This timeframe is crucial to maintain the safety and airworthiness of the aircraft, thereby preventing potential hazards during flight operations. The installation must be carried out in accordance with the specified technical requirements to ensure that the safety cable effectively performs its intended function.
Breach of the requirements outlined in the AD/PA-25/7 could result in significant consequences under the Civil Aviation Regulations 1998. Specifically, operating an aeroplane without the mandated safety cable could lead to civil penalties. The Civil Aviation Safety Authority has the authority to impose fines, and in severe cases, the operator may face suspension or revocation of their air operator certificate. Additionally, failure to comply with these directives may also result in criminal charges, leading to imprisonment, particularly if the non-compliance results in an aviation incident or accident. The maximum penalties for such breaches are determined by the severity of the violation and the associated risks to aviation safety.