AD/PC-12/5 - Hydraulic Hand Pump

Overview

The Civil Aviation Regulations 1998, enacted by the Commonwealth of Australia, address the need for stringent safety measures in the operation of civil aircraft. A specific legislative instrument within this framework, F2006B06107, focuses on the airworthiness directives for Pilatus PC-12 Series Aeroplanes. This directive, AD/PC-12/5, was introduced to address a critical safety issue identified in the hydraulic hand pump of certain PC-12 aircraft. The problem stemmed from a potential failure of the non-return valve in the hydraulic hand pump, which could result in the hand pump handle coming into contact with the top of the nose wheel well. Such contact could force the pump body to move upwards and impact on the PCL quadrant assembly, leading to stiff PCL movement during flight. The directive mandates compliance with Pilatus modification 960341 as specified in Pilatus PC XII Service Bulletin No 29-001 dated July 1996. Compliance with this directive is crucial, requiring action within 300 hours time in service from an effective date of 30 January 1997 or by 30 April 1997, whichever comes first. The policy objective is to ensure the continued safety and reliability of the aircraft, mitigating the risk of in-flight mechanical failures.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, addresses the application of airworthiness directives for certain aircraft, with AD/PC-12/5 focusing on Pilatus PC-12 Series Aeroplanes. This legislation applies to all Pilatus PC-12 aircraft with serial numbers ranging from 101 to 153, requiring compliance with the specified modification to ensure continued safe operation. The requirement is to incorporate Pilatus modification 960341, detailed in Service Bulletin No 29-001 dated July 1, 1996, in response to a reported failure of the hydraulic hand pump's non-return valve. This failure led to significant mechanical issues, including stiff PCL movement during flight, necessitating timely compliance. The directive mandates action within 300 hours of time in service from the effective date of January 30, 1997, or by April 30, 1997, whichever comes first, to mitigate the identified safety risks.

Key Provisions

The key provisions of the Civil Aviation Safety Authority (CASA) Schedule of Airworthiness Directives for Pilatus PC-12 Series Aeroplanes, specifically AD/PC-12/5, focus on addressing a critical hydraulic system issue (Part 39, 105). The directive mandates that all PC-12 aircraft with serial numbers ranging from 101 to 153 must incorporate a specific modification, namely Pilatus modification 960341, as outlined in Pilatus PC XII Service Bulletin No 29-001 dated July 1, 1996 (s 1). This modification is a response to a reported failure of the hydraulic hand pump's non-return valve, which led to significant operational risks (s 2). Under the requirements of the directive, the specified modification must be implemented within a stringent timeframe. Operators must ensure compliance either within 300 hours of time in service from the effective date of January 30, 1997, or by April 30, 1997, whichever comes first (s 3). This ensures that the issue is addressed promptly to maintain the safety and airworthiness of the aircraft. The directive references a Swiss FOCA AD HB96-139 dated March 18, 1996, indicating international collaboration and alignment in addressing this safety concern (s 4). Failure to comply with the requirements set out in AD/PC-12/5 could result in severe consequences. The directive underscores the importance of adhering to the specified modification to prevent potential hazards, such as the hand pump handle coming into contact with the nose wheel well, which could lead to the pump body impacting the PCL quadrant assembly (s 5). This impact could cause the PCL movement to become stiff during flight, posing a significant risk to the aircraft's operational safety and the well-being of those on board. Operators found in breach of these safety requirements could face substantial penalties and legal repercussions, further emphasising the critical nature of compliance (s 6).