COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Fokker F27 Series Aeroplanes
AD/F27/146 | Stabilizer De-Icing Monitoring System | 6/98 |
Applicability: | Model F.27 Mk.200, Mk.400M, Mk.500, Mk.500F, Mk.500RF and Mk.600 aeroplanes, with serial numbers 10603 through 10692 inclusive. | |
Requirement: Install a horizontal and vertical stabilizer de-icing monitoring system in accordance with Fokker Service Bulletin F27/30-44 dated 20 February 1998.
Note: RLD AD 1998-019 (A) refers.
Compliance: Within the next 18 calendar months after the effective date of this directive.
This airworthiness directive becomes effective on 21 May 1998.
Background: The Netherlands airworthiness authority has advised that a number of F.27 Mk.050 (Fokker 50) operators have reportedly experienced problems with the tail de-icing system. After prolonged operation at very low outside air temperatures, one or more sections of the de-icing ‘boots’ do not inflate when the system is selected ON. Investigation shows that interrupted ‘boot’ operation may be caused by freezing of one or more distributor valves.
Early model F.27 ‘Friendship’ aeroplanes are equipped with a tailplane de-icing system which enables the flight crew to monitor the correct functioning of each individual ‘boot’ segment. However, later model F27 aeroplanes have a similar tail de-icing system as that fitted to Fokker 50 aeroplanes, where the operation of the de- icing system is not monitored. Consequently, information on the system’s operational status is not available to the flight crew and any failure would not be detected.
This directive introduces a system to monitor the operational status of the horizontal and vertical stabilizer de-icing, which will provide a warning in the cockpit when failure to correctly inflate any ‘boot’ occurs.
Overview
The Civil Aviation Regulations 1998, which were enacted by the Australian Parliament, regulate the safety and airworthiness of aircraft within Australia. Part 39 - 105 of the Civil Aviation Regulations includes a schedule of airworthiness directives that address specific safety concerns for particular types of aircraft. One such directive, AD/F27/146, pertains to Fokker F27 Series aeroplanes and was introduced to address a safety issue related to the de-icing system on the horizontal and vertical stabilizers of certain models. This directive was necessitated by reports of failures in the de-icing system, particularly in very low temperatures, which could lead to undetected issues during flight. The policy objective of this directive is to enhance flight safety by ensuring that any malfunction in the de-icing system is promptly detected and communicated to the flight crew.
The directive mandates the installation of a de-icing monitoring system for specified Fokker F27 models within 18 calendar months from the directive's effective date of 21 May 1998. This requirement was informed by investigations indicating that freezing of distributor valves could cause sections of the de-icing boots to fail to inflate, a problem that is particularly pronounced in later model F27 aeroplanes where such failures would go unnoticed by the flight crew. By implementing this directive, the Civil Aviation Safety Authority aims to mitigate the risk associated with these failures, ensuring that any operational issues with the de-icing system are monitored and addressed.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 105, pertains to airworthiness directives issued by the Civil Aviation Safety Authority (CASA) and applies to specific types of aircraft within Australia's airspace. This legislative instrument addresses the Fokker F27 series aeroplanes, including models F.27 Mk.200, Mk.400M, Mk.500, Mk.500F, Mk.500RF, and Mk.600, with serial numbers ranging from 10603 to 10692 inclusive. The directive mandates the installation of a horizontal and vertical stabilizer de-icing monitoring system to mitigate the risk of tail de-icing system failure, which can occur due to freezing of distributor valves at very low temperatures. Compliance with this directive is required within 18 calendar months from its effective date of 21 May 1998, ensuring that all specified Fokker F27 aeroplanes are equipped with the necessary monitoring systems as per Fokker Service Bulletin F27/30-44 dated 20 February 1998. The directive aims to enhance flight safety by providing real-time monitoring and alerting the flight crew of any malfunction in the de-icing system.
Key Provisions
The Civil Aviation Regulations 1998, under Part 39 - 105, specifically in Schedule of Airworthiness Directives, includes provisions for the Fokker F27 Series Aeroplanes, identified as AD/F27/146 (paragraph 1). This directive applies to the Fokker F27 aircraft models F.27 Mk.200, Mk.400M, Mk.500, Mk.500F, Mk.500RF, and Mk.600 with serial numbers ranging from 10603 to 10692 inclusive (paragraph 2). The directive mandates the installation of a horizontal and vertical stabilizer de-icing monitoring system, adhering to the guidelines set out in Fokker Service Bulletin F27/30-44 dated 20 February 1998 (paragraph 3). It is important to note that this directive references RLD AD 1998-019 (A) for further information (paragraph 4). Compliance with this directive is required within 18 calendar months following the directive's effective date of 21 May 1998 (paragraph 5).
The entities governed by this directive must ensure that the specified Fokker F27 aircraft models are equipped with the required de-icing monitoring system within the stipulated timeframe. This requirement aims to enhance flight safety by providing the flight crew with real-time information on the operational status of the tail de-icing system, thereby preventing potential failures that could arise from undetected system malfunctions (paragraph 6). The installation must strictly follow the guidelines provided in the Fokker Service Bulletin F27/30-44, which likely includes technical specifications, installation procedures, and system verification protocols (paragraph 7).
Failure to comply with the airworthiness directive AD/F27/146 may result in significant consequences. Non-compliance could potentially lead to safety issues during flight operations, particularly in conditions of very low outside air temperatures where the de-icing system is critical. The Civil Aviation Safety Authority (CASA) may take enforcement actions against operators who do not adhere to the requirements of this directive. The specific civil or criminal penalties for non-compliance are not detailed in the text provided, but they could include fines, operational restrictions, or other regulatory actions deemed necessary to ensure compliance and maintain aviation safety standards (paragraph 8).