AD/AC/70 - Engine Oil Breather Line - Modification

Overview

The Civil Aviation Regulations 1998, which were enacted to establish and maintain standards for civil aviation in Australia, include the legislative instrument F2006B02130. This particular regulation addresses a gap in safety requirements for specific models of the Twin Commander (Gulfstream/Rockwell/Aerocommander 500, 600 and 700) series aeroplanes. The problem it seeks to resolve is the potential blockage of the primary oil breather line vent by ice, which could lead to engine failure. This issue was identified by the manufacturer and requires the implementation of modifications as outlined in the Airworthiness Directive AD/AC/70. The policy objective is to ensure the airworthiness of these aircraft through compliance with safety directives, thereby enhancing the overall safety of civil aviation operations in Australia. The regulation was enacted by the Australian Parliament under the authority granted by the Civil Aviation Act 1988.

Scope and Application

The Civil Aviation Regulations 1998, under Part 39 - 105, specifically the Airworthiness Directives, pertain to the safety and operational standards of civil aircraft within Australian jurisdiction. This particular legislation applies to the Twin Commander series aeroplanes, namely the Gulfstream/Rockwell/Aerocommander 500, 600, and 700 models, that have undergone modifications as per STCs SA2691WE or SA2891WE, specifically for the Lycoming IO-720 conversion. The directive mandates compliance within 100 hours of time in service following 31 August 1979. The legislation’s objective is to address safety concerns by modifying the engine oil breather line to prevent blockage by ice during flight, thereby ensuring the continued airworthiness of these aircraft within the Australian aviation sector. This regulatory framework extends across all operators and owners of the specified aircraft models within Australia, with compliance overseen by the Civil Aviation Safety Authority.

Key Provisions

The key sections of the Civil Aviation Regulations 1998, particularly Part 39 - 105, mandate that specific modifications be made to the engine oil breather line of certain Twin Commander series aeroplanes. The applicable models include 680F, 680F(P), 680FL, and 680FL(P), which must have undergone modifications as per STCs SA2691WE or SA2891WE (Lycoming IO-720 conversion). According to section (8/79), these modifications must be carried out within 100 hours of the aeroplane's time in service following 31 August 1979. The directive references Mr. R.P.M. Inc. SB No. 004 as the document detailing the necessary changes. These provisions impose clear obligations on the operators of the specified Twin Commander aeroplanes. They must ensure that the required modifications to the engine oil breather line are completed within the stipulated timeframe. Failure to adhere to these modifications could lead to the aeroplane not meeting the necessary airworthiness standards. Compliance with these modifications is critical for safety and to avoid any operational restrictions or penalties that might be imposed by the Civil Aviation Safety Authority (CASA). Breach of the requirements outlined in the Civil Aviation Regulations can lead to serious consequences. If operators do not comply with the modifications specified in the Airworthiness Directive (AD/AC/70), they may face enforcement actions from CASA. This can include fines, penalties, or the grounding of the aeroplane until the required modifications are made. The specific penalties are not detailed in the extract, but generally, non-compliance with CASA directives can result in significant financial penalties and operational disruptions for the non-compliant party.