AD/CESSNA 550/18 - Brake Shuttle Valve

Overview

The Civil Aviation Regulations 1998, specifically Part 39 - 105, addresses the safety of civil aviation in Australia by setting out the requirements for airworthiness directives. Enacted by the Commonwealth of Australia, these regulations are designed to ensure that all aircraft meet the necessary safety standards. The legislation aims to mitigate risks associated with aircraft operation, including issues related to the structural integrity and operational safety of specific models. AD/CESSNA 550/18 focuses on the Cessna 550 (Citation II) Series Aeroplanes, addressing a particular problem of brake shuttle valve leakage which has been reported due to the deterioration of o-ring material caused by exposure to an incompatible seal lubricant. The objective is to ensure the ongoing airworthiness of these aircraft by mandating regular inspections and replacements as specified in the associated service bulletins and alert service letters. This legislative instrument was enacted to provide clear guidance and requirements for maintaining the safety of these aircraft, thereby protecting both the passengers and the operational integrity of the aviation industry. It sets out a compliance schedule that necessitates inspections and repairs within specified time intervals to prevent potential safety hazards. By doing so, the Civil Aviation Regulations 1998 aim to uphold the highest standards of aviation safety within Australia.

Scope and Application

The Civil Aviation Regulations 1998, specifically under Part 39 - 105, pertains to the Civil Aviation Safety Authority's Schedule of Airworthiness Directives, which mandates compliance for certain types of aircraft. For Cessna 550 (Citation II) series aeroplanes, the AD/CESSNA 550/18 regulation requires inspections and replacements of brake shuttle valves for models 550 and 551 with unit numbers ranging from -0002 through -0619 and -0621 through -0623, as well as for model S550 with unit numbers from -0001 through -0160, provided they are equipped with BF Goodrich brakes and have incorporated SB S550-32-7. This regulation applies to aircraft operations within the Commonwealth of Australia, thereby ensuring the safety standards set by the Civil Aviation Safety Authority are met nationally. Compliance with the regulation necessitates inspections according to Cessna Alert Service Letters SLA 550-32-38 and SLA S550-32-15, and the replacement of brake shuttle valves as outlined in BF Goodrich Service Bulletin SB 517. The inspection must occur within 50 hours of time in service following 17 May 1990, and subsequently at intervals not exceeding 50 hours, until BF Goodrich SB 517 is fully incorporated. For model S550, the replacement must be completed within 200 hours of time in service after the same date. This directive is grounded in the reports of leaking shuttle valves due to the deterioration of shuttle valve o-ring material caused by exposure to an incompatible seal lubricant.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 105, establish the Civil Aviation Safety Authority (CASA) Schedule of Airworthiness Directives, which include detailed instructions for maintaining aircraft safety. Section AD/CESSNA 550/18 pertains to the Cessna 550 (Citation II) series aeroplanes, addressing an issue with brake shuttle valves. This section applies to specific models of the Cessna 550 and 551 series, as well as the model S550, with certain unit numbers and equipped with BF Goodrich brakes. The directive mandates an inspection of the brake shuttle valves in accordance with specified service letters (Section 1). For models 550 and 551, inspections must be carried out as per Cessna alert Service Letter SLA 550-32-38, and for model S550, inspections should be done as per Cessna Alert Service Letter SLA S550-32-15. Additionally, the directive requires that the brake shuttle valves be replaced according to BF Goodrich Service Bulletin SB 517 (Section 2). Entities governed by this directive must ensure compliance with the outlined inspection and replacement procedures. For models 550 and 551, inspections must be performed within 50 hours of time in service after 17 May 1990 and subsequently at intervals not exceeding 50 hours until BF Goodrich SB 517 is incorporated. For model S550, inspections must be conducted within 200 hours of time in service after 17 May 1990 (Section 1). Compliance with these requirements is critical for maintaining the airworthiness of the affected aircraft. Failure to adhere to the provisions of this directive may result in significant consequences. The Civil Aviation Regulations 1998 impose penalties for non-compliance with airworthiness directives, which may include fines and other legal actions. The specific penalties are not detailed in the referenced legislative instrument but generally align with the regulatory framework governing civil aviation safety. Ensuring that the inspections and replacements are carried out as mandated is essential to avoid potential safety risks and legal repercussions.