AD/PA-25/31 - Rapid Throttle Movement - Warning Placard

Overview

The Civil Aviation Regulations 1998, as amended by the legislative instrument F2006B05567, address specific safety concerns related to the Piper PA-25 (Pawnee) Series Aeroplanes. This instrument, enacted by the Australian Parliament, was introduced to mitigate risks associated with rapid throttle movements in Piper PA-25 models equipped with certain Lycoming 0-320 engines and Marvel Schebler MA-4 carburettor model. The policy objective is to ensure the airworthiness of these aircraft by requiring the installation of a warning placard, as documented in Piper Service Letter No. 644. The requirement mandates compliance within 10 hours of time in service following 28 November 1972, ensuring that operators are promptly informed of the potential hazards and can take appropriate action to maintain safety standards.

Scope and Application

The Civil Aviation Regulations 1998, specifically PART 39 - 105, outlines the Civil Aviation Safety Authority’s Schedule of Airworthiness Directives, which includes AD/PA-25/31 concerning the Piper PA-25 (Pawnee) Series Aeroplanes. This directive is applicable to any Piper PA-25 aircraft fitted with a Lycoming 0-320 engine equipped with a Marvel Schebler carburettor model MA-4, with the part number I0-3678-32. The regulation mandates compliance within 10 hours of time in service after 28 November 1972, as referenced in Piper SL No. 644. This Act applies to the specified model and engine configuration of aircraft, ensuring that they meet certain safety standards related to rapid throttle movement by requiring the installation of a warning placard. The regulations are enforced by the Civil Aviation Safety Authority, and compliance is mandatory for all relevant aircraft within the Australian jurisdiction. The directive does not extend to other aircraft models or engine configurations unless specifically mentioned in other airworthiness directives or amendments to this regulation.

Key Provisions

The main operative sections of the Civil Aviation Regulations 1998, specifically within PART 39 - 105, pertain to the airworthiness directives for Piper PA-25 (Pawnee) series aeroplanes. The directive AD/PA-25/31 mandates that a warning placard must be installed on model PA-25 aeroplanes equipped with Lycoming 0-320 engines and Marvel Schebler carburettor model MA-4, specifically P/No. I0-3678-32 (section 5/73). This directive applies to aircraft that meet the specified criteria and is referenced in Piper Service Letter No. 644. Compliance with this directive must occur within 10 hours of time in service after the directive's effective date of 28 November 1972. The obligations imposed by this directive require aircraft owners or operators to ensure that the specified warning placard is correctly installed on their Piper PA-25 aeroplanes. This involves verifying that the aircraft model and engine type match the directive's requirements and that the placard is appropriately affixed as per the guidance provided in Piper Service Letter No. 644. Operators must also ensure that the compliance period is observed, installing the placard within the stipulated 10 hours of service time following 28 November 1972. Failure to comply with the airworthiness directive AD/PA-25/31 may result in significant consequences. Under the Civil Aviation Regulations, non-compliance can be considered an offence, leading to potential enforcement actions by the Civil Aviation Safety Authority (CASA). The severity of penalties can include fines and, in more serious cases, grounding of the aircraft until the directive is complied with. The exact penalties are determined by CASA based on the specific circumstances of the non-compliance, but they can be substantial, reflecting the importance of adhering to airworthiness directives to ensure aviation safety.