AD/BN-2/25 Amdt 3 - Wing Mounted Engine Upper Mounting Brackets

Overview

The Civil Aviation Regulations 1998 (Cth), as amended by the Legislative Instrument F2006B04736, addresses issues related to the airworthiness of Pilatus Britten-Norman BN-2 Series Aeroplanes. Specifically, this legislative instrument focuses on safety directives concerning the wing-mounted engine upper mounting brackets on BN-2 and BN-2T Islander Series aircraft. The problem it was introduced to address includes the development of cracks across the mounting bracket lugs, elongation and wear at the main bolt holes, and potential lug assembly distortion and fretting, all of which can compromise the structural integrity of the aircraft. Enacted by the Australian Parliament, the policy objective of this regulation is to ensure compliance with safety standards to prevent such defects, thereby enhancing the safety of civil aviation. The regulatory amendment through F2006B04736 clarifies the requirements for addressing these issues, ensuring that all relevant actions are undertaken as specified in the Pilatus Britten-Norman S.B. BN-2/SB.61 issue 5. This amendment aims to eliminate any ambiguity in the directive's intent, ensuring that all necessary actions are clearly defined and must be accomplished unless already completed, as detailed in the requirement document. By doing so, the Civil Aviation Safety Authority ensures that the aviation safety standards are upheld, protecting both the passengers and the aircraft.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, applies to all persons and entities involved in the operation of Pilatus Britten-Norman BN-2 Series aeroplanes, including both Model BN-2 and BN-2T Islander Series. The regulation mandates that these aircraft must comply with Airworthiness Directives concerning the upper mounting brackets of wing-mounted engines. The requirement stipulates adherence to the actions detailed in Pilatus Britten-Norman Service Bulletin BN-2/SB.61 issue 5, which addresses issues such as cracks in the mounting bracket lugs, elongation and wear at the main bolt holes, lug assembly distortion, and fretting between the main bolt hole lug and bush where fitted. Compliance with this directive is mandatory unless the required actions have already been accomplished, as detailed in the requirement document. The regulation applies nationally within the Commonwealth of Australia and extends to all aircraft of the specified series, irrespective of their location or the nature of their operations within Australian airspace. There are no stated exclusions or exemptions in this directive, and it does not specify any particular thresholds that would limit its application. The scope of the directive can be extended or refined through subordinate instruments, as deemed necessary by the Civil Aviation Safety Authority.

Key Provisions

The Civil Aviation Regulations 1998, particularly in Part 39, establish specific directives concerning the airworthiness of certain aircraft models. In this context, Section 39-105 of the Schedule of Airworthiness Directives pertains to the Pilatus Britten-Norman BN-2 Series Aeroplanes, with a particular focus on Amendment 3 related to Wing Mounted Engine Upper Mounting Brackets. This directive, identified as AD/BN-2/25Amdt 3, applies to all Model BN-2 and BN-2T Islander Series aircraft and mandates compliance in accordance with Pilatus Britten-Norman S.B. BN-2/SB.61 issue 5. The directive requires actions as detailed in the Requirement Document, unless these actions have already been completed. The obligations imposed by this directive are clear and specific. Owners and operators of BN-2 and BN-2T Islander Series aircraft must ensure that any identified issues related to the wing mounted engine upper mounting brackets are addressed. This includes rectifying any cracks across the mounting bracket lugs, main bolt holes, and reinforcing doubler securing rivet locations, as well as addressing elongation and wear at the main bolt holes. Furthermore, operators must deal with potential lug assembly distortion and fretting between the main bolt hole lug and bush where fitted. Any faulty lug doubler plate sub-assembly at manufacture leading to unacceptable lug edge distances must also be corrected. Failure to comply with the requirements set out in this directive can result in severe consequences. While the specific civil or criminal penalties are not detailed in the provided text, non-compliance with airworthiness directives under the Civil Aviation Regulations 1998 generally leads to enforcement actions by the Civil Aviation Safety Authority (CASA). Such actions can include fines, suspension or revocation of airworthiness certificates, and potentially criminal charges if the non-compliance is found to have endangered safety. The maximum penalties can vary widely depending on the severity and impact of the non-compliance, but they are designed to ensure stringent adherence to safety standards in civil aviation.