COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Cessna 400 Series Aeroplanes
AD/CESSNA 400/95 Pilot’s Instruments Air System 11/88
Applicability: Models 425 equipped with pneumatic gyro instruments in the left instrument panel and approved for IFR operations.
Requirement: Action in accordance with CESSNA Service Bulletin CQB 88-9 and Service Kit SK425-41.
Compliance: Not later than 31 March 1989.
Background: The existing instrument air pressure regulator by itself is not capable of operating at high overpressure conditions and may close and shut off airflow to the attitude and directional gyros. In the event an overpressure condition failure occurs, the additional regulator installed per this AD is designed to provide reduced air pressure at an acceptable value to the inlet of the existing regulator to assist it in operating normally.
Overview
The Civil Aviation Regulations 1998, under Part 39, address specific safety directives for aviation operations, including the Airworthiness Directive (AD) concerning Cessna 400 series aeroplanes. Enacted by the Civil Aviation Safety Authority, this legislation was introduced to address a critical safety concern identified with certain models of Cessna aeroplanes. Specifically, the AD/CESSNA 400/95 focuses on the pilot’s instruments air system for models 425 equipped with pneumatic gyro instruments in the left instrument panel and approved for IFR operations. The primary objective of this directive is to rectify a potential failure of the instrument air pressure regulator during high overpressure conditions, which could lead to the shutdown of airflow to essential gyro instruments. Compliance with this directive requires adherence to CESSNA Service Bulletin CQB 88-9 and Service Kit SK425-41, with an implementation deadline set for 31 March 1989. This directive aims to enhance the reliability and safety of the aircraft’s air system, ensuring it can operate effectively even under adverse conditions.
Scope and Application
The Civil Aviation Regulations 1998, specifically under PART 39 - 105, mandates that the Civil Aviation Safety Authority (CASA) issue Airworthiness Directives (AD) to ensure the safety and airworthiness of aircraft. This particular AD/CESSNA 400/95 applies to Cessna 425 models equipped with pneumatic gyro instruments in the left instrument panel and approved for instrument flight rules (IFR) operations. The directive requires compliance with CESSNA Service Bulletin CQB 88-9 and Service Kit SK425-41, with an action to be completed by 31 March 1989. This AD is designed to address an issue where the existing instrument air pressure regulator may fail under high overpressure conditions, potentially leading to the shutdown of airflow to the attitude and directional gyros. The installation of an additional regulator, as specified in the service bulletin and kit, ensures that the system can operate normally under such conditions. The geographic and jurisdictional reach of this regulation is national, applying across Australia in accordance with the Civil Aviation Regulations 1998. No specific exclusions, exemptions, or thresholds are mentioned in this directive, indicating that it applies universally to the specified models and conditions. The scope of the regulation may be further extended or clarified through subordinate instruments issued by CASA.
Key Provisions
The Civil Aviation Regulations 1998, specifically Part 39 - 105, mandates the maintenance and airworthiness standards for certain aircraft, including the Cessna 400 series aeroplanes. Under this part, the Cessna 400/95 Airworthiness Directive (AD) addresses the issue of the pilot's instruments air system for models 425 equipped with pneumatic gyro instruments in the left instrument panel and approved for IFR operations (Section 39 - 105 AD/CESSNA 400/95). The directive requires compliance with CESSNA Service Bulletin CQB 88-9 and Service Kit SK425-41 to ensure the air system operates correctly under various conditions, particularly high overpressure situations that could potentially shut off airflow to the attitude and directional gyros.
To meet these requirements, operators must ensure that the specified action is taken on the aircraft's air system. This involves installing an additional regulator to provide reduced air pressure at an acceptable value to the inlet of the existing regulator, thereby assisting it in operating normally even under high overpressure conditions (Section 39 - 105 AD/CESSNA 400/95). This modification must be completed not later than 31 March 1989 to ensure compliance with the directive.
The Civil Aviation Regulations impose specific obligations on the operators of Cessna 400 series aeroplanes covered by this directive. Operators are required to inspect and, if necessary, modify the pilot’s instruments air system to include the additional regulator as specified in the CESSNA Service Bulletin CQB 88-9 and Service Kit SK425-41. This is to maintain the airworthiness of the aircraft and ensure the safety of flight operations, particularly in high overpressure conditions that could otherwise compromise the functionality of the gyro instruments (Section 39 - 105 AD/CESSNA 400/95).
Failure to comply with the provisions of the Civil Aviation Regulations and the specific requirements of the Cessna 400/95 AD could result in severe consequences. Operators who do not adhere to the mandated modifications may face civil penalties, including fines and potential grounding of the affected aircraft. Additionally, operating a non-compliant aircraft could lead to criminal charges, especially if such non-compliance results in an incident or accident. The precise penalties are not detailed in the legislative instrument, but they can include substantial financial penalties and imprisonment depending on the severity of the breach and its impact on aviation safety (Section 39 - 105 AD/CESSNA 400/95).