AD/PA-23/20 - Stabilator Tab Horn - Modification

Overview

The Civil Aviation Regulations 1998, specifically under Part 39 - 105, were enacted to ensure the safety and maintenance of aircraft within Australia. This piece of legislation was introduced by the Australian Government to address the need for standardised safety measures and directives for specific aircraft models, including the Piper PA-23 (Apache and Aztec) series aeroplanes. The Civil Aviation Safety Authority (CASA), which is the enforcing body, aims to mitigate risks and ensure the highest standards of airworthiness and safety in the Australian aviation sector. AD/PA-23/20, concerning the stabilator tab horn modification for certain Piper PA-23 series aeroplanes, was issued to rectify identified safety issues and ensure compliance with safety directives within a specified timeframe. The Piper PA-23 (Apache and Aztec) series aeroplanes covered by this directive, with specific serial numbers, must comply with the stabilator tab horn modification outlined in Piper Service Bulletin No. 189. This directive requires that the modification be completed within 60 hours of the aeroplane's time in service after 19 August 1960. The policy objective is to enhance the structural integrity and operational safety of these aircraft, thereby reducing the likelihood of accidents and ensuring adherence to safety standards mandated by CASA.

Scope and Application

The Civil Aviation Safety Authority’s Schedule of Airworthiness Directives under the Civil Aviation Regulations 1998, specifically Part 39 - 105, governs the safety and airworthiness standards of aircraft operating within Australia. This regulation applies to the Piper PA-23 (Apache and Aztec) Series Aeroplanes, particularly to those with serial numbers falling within the specified range: PA-23-250 with serial numbers 27-2 to 27-5, 27-7 to 27-60, and 27-62 to 27-215. The directive mandates compliance with modifications to the stabilator tab horn as outlined in Piper Service Bulletin No. 189, requiring these changes to be implemented within 60 hours of time in service following 19 August 1960. This regulation ensures that the specified aircraft meet the necessary safety standards to operate within Australian airspace, thereby safeguarding the integrity and safety of civil aviation activities across the nation.

Key Provisions

The Civil Aviation Regulations 1998 (Cth) in Part 39 - 105, under the Civil Aviation Safety Authority (CASA) Schedule of Airworthiness Directives, include specific requirements for the Piper PA-23 (Apache and Aztec) series aeroplanes, particularly in relation to the stabilator tab horn modification (AD/PA-23/20). The directive applies to model PA-23-250 with serial numbers (S/Nos.) ranging from 27-2 to 27-5, 27-7 to 27-60, and 27-62 to 27-215. Compliance with these requirements must be achieved within 60 hours of the aeroplane's time in service following 19 August 1960, as detailed in Piper Service Bulletin No. 189. The operative sections of this legislation mandate that the stabilator tab horn on specified Piper PA-23 models must be modified to prevent potential failures that could compromise the aircraft's control surfaces. This modification is essential to ensure the continued airworthiness of these aeroplanes. Specifically, the modification must be implemented to address any structural deficiencies that could lead to the stabilator tab detaching from the aeroplane, which could, in turn, result in loss of control. Entities and individuals governed by these regulations must adhere to the compliance timeline and ensure that the stabilator tab horn is modified as per the specifications outlined in Piper Service Bulletin No. 189. Failure to comply with these directives within the stipulated timeframe can lead to severe operational consequences, including the grounding of the aeroplane until the required modifications are completed. This not only affects the operational readiness of the aircraft but also poses significant safety risks. The Civil Aviation Regulations 1998 impose strict obligations on operators, owners, and maintenance personnel to ensure that the stabilator tab horn modifications are carried out correctly and verified by CASA-approved personnel. Non-compliance with these directives can result in severe penalties. Under section 105 of the Regulations, any violation may lead to enforcement actions by CASA, which can include fines, suspension of airworthiness certificates, and potential criminal charges for individuals responsible for the oversight. The maximum penalties for these offences are substantial, reflecting the critical nature of maintaining the airworthiness of these aeroplanes.