AD/CESSNA 150/45 - STOL Conversion Wing Stall Fence

Overview

The Civil Aviation Regulations 1998, specifically Part 39 - 105, includes Airworthiness Directives designed to maintain the safety standards of aircraft within Australia. One such directive, AD/CESSNA 150/45, addresses the specific issue of Cessna 150, F150, 152 & F152 series aeroplanes fitted with "Bush Conversions Inc." Short Take Off and Landing (STOL) kits. This directive was enacted to mitigate the risk of the aircraft entering a stall condition due to the improper height of the wing stall fence, which could potentially lead to loss of control. The policy objective is to ensure that any modifications to the aircraft do not compromise safety and that all modifications are compliant with the standards set forth by the Civil Aviation Safety Authority (CASA). The directive requires that the height of the wing stall fence is measured and, if necessary, adjusted to meet the specified requirements to prevent any unsafe conditions.

Scope and Application

The Civil Aviation Safety Authority (CASA) Regulations 1998, specifically within Part 39 - 105, encompasses the Airworthiness Directives concerning the Cessna 150, F150, 152 & F152 Series Aeroplanes. This particular directive, AD/CESSNA 150/45, is applicable to any model of these aircraft that has been fitted with a "Bush Conversions Inc." Short Take Off and Landing (STOL) kit, as per FAA STC SA1371SW. The directive requires the measurement of the height of the wing stall fence at the trailing edge. If this height exceeds 32.5 mm (1.28 inches), the installation of a smaller fence must be carried out in accordance with a scheme approved by the CASA through a District Office. This directive is designed to ensure that aircraft equipped with this specific STOL kit do not enter a stall condition, which could lead to loss of control, by ensuring that the stall fence height does not exceed the specified limit. Compliance with this directive must be achieved within 100 hours of time in service after 12 September 1996.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 105, addresses the airworthiness directives for certain Cessna aircraft models, including the Cessna 150, F150, 152, and F152 series aeroplanes. Under this regulation, one directive pertains to the STOL conversion wing stall fence for aircraft fitted with a "Bush Conversions Inc." STOL kit installed according to FAA STC SA1371SW. The directive requires the measurement of the height of the wing stall fence at the trailing edge, ensuring it does not exceed 32.5 mm (1.28 inches). If the height is found to be greater, a smaller fence must be installed in accordance with a scheme approved through a District Office of the Authority (section 39-105). These regulations impose obligations on the operators and owners of the specified Cessna aircraft models. They must ensure that the height of the wing stall fence is measured and adjusted if necessary, within 100 hours of time in service after 12 September 1996. The requirement mandates that the installation of a smaller fence, if required, must comply with a scheme approved by the Civil Aviation Safety Authority, reinforcing the importance of adhering to safety standards to prevent the aircraft from entering a stall condition due to excessive stall fence height. Failure to comply with the airworthiness directive can result in significant consequences. While the specific penalties are not detailed in the text, non-compliance with Civil Aviation Regulations can typically lead to enforcement actions, fines, and potential grounding of the aircraft until the required modifications are made. Additionally, there may be civil and criminal penalties for operators and owners who fail to ensure the airworthiness of their aircraft, as mandated by the Civil Aviation Act 1988 and other relevant legislation. These consequences underscore the importance of adhering to the specified requirements to ensure the safety and airworthiness of the aircraft.