COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Fokker F27 Series Aeroplanes
AD/F27/38 ADF Sense Antenna - Modification 12/67
Applicability: All models fitted with Bendix type DFA-70A ADF equipment.
Requirement: Modify the sense antenna to achieve the following minimum performance characteristics:-
(a) Effective Height : Not less than 0.25 metres.
(b) Sensitivity Product Value : Between the limits of 12 and 25 micro-microfarads- meters.
(c) Total capacity of antenna and transmission line presented to receiver input terminals : 270 micro-microfarads + 10%.DE
(d) Tilt Angle : between the limits of -20º and +10º.
Overview
The Civil Aviation Regulations 1998, enacted by the Parliament of the Commonwealth of Australia, form a critical framework governing civil aviation safety. One component of these regulations is the Civil Aviation Safety Authority (CASA) Schedule of Airworthiness Directives, which includes specific directives such as AD/F27/38 concerning Fokker F27 Series Aeroplanes. This particular directive addresses a safety concern related to the Automatic Direction Finder (ADF) sense antenna, mandating its modification to ensure it meets specified performance criteria. The directive aims to mitigate potential operational risks associated with the ADF system by ensuring that the sense antenna maintains certain parameters, such as effective height, sensitivity product value, total capacity, and tilt angle. By implementing these requirements, CASA seeks to enhance the safety and reliability of Fokker F27 Series Aeroplanes in operation.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 105, outlines the Civil Aviation Safety Authority's (CASA) Airworthiness Directives for aircraft, with AD/F27/38 focusing on Fokker F27 Series aeroplanes fitted with Bendix type DFA-70A Automatic Direction Finding (ADF) equipment. This directive applies to all models of Fokker F27 aeroplanes that are equipped with the specified ADF system. The requirement is to modify the ADF sense antenna to meet certain performance characteristics, ensuring the operational safety and compliance of the aircraft with aviation standards. The modifications must achieve an effective height of no less than 0.25 metres, a sensitivity product value between 12 and 25 micro-microfarads-meters, a total capacity of the antenna and transmission line presented to receiver input terminals of 270 micro-microfarads plus 10%, and a tilt angle between -20º and +10º.
This regulation has a national reach within the Commonwealth of Australia, as it is a part of the Civil Aviation Regulations, which are enforced by CASA. The scope of the regulation is limited to Fokker F27 Series aeroplanes with the specified ADF equipment, and it does not explicitly state any exclusions, exemptions, or thresholds beyond the defined modifications. The application of these directives may be extended or further specified through subordinate instruments issued by CASA, ensuring that all relevant parties are aware of and comply with the necessary safety standards.
Key Provisions
The Civil Aviation Regulations 1998, specifically Part 39 - 105, contains provisions regarding the airworthiness directives for Fokker F27 Series aeroplanes, which are detailed in the Airworthiness Directive AD/F27/38 (section 12/67). This directive pertains to the modification of the sense antenna for all Fokker F27 models equipped with the Bendix type DFA-70A Automatic Direction Finder (ADF) equipment. The directive mandates that the sense antenna be modified to meet specific performance criteria to ensure the aircraft's continued airworthiness.
Under this directive, the sense antenna must be modified to achieve certain minimum performance characteristics to maintain compliance with safety standards. These requirements include maintaining an effective height of not less than 0.25 metres (section 12/67(a)), ensuring the sensitivity product value falls within the range of 12 to 25 micro-microfarads-meters (section 12/67(b)), and achieving a total capacity of the antenna and transmission line presented to the receiver input terminals of 270 micro-microfarads + 10% (section 12/67(c)). Additionally, the tilt angle of the antenna must be within the range of -20º to +10º (section 12/67(d)). These modifications are essential to ensure the ADF equipment operates correctly and reliably, thereby enhancing the overall safety of the aircraft.
Operators and owners of Fokker F27 Series aeroplanes must ensure that the required modifications to the ADF sense antenna are carried out by qualified personnel. The operators are responsible for verifying that the modifications meet the specified performance characteristics and that the aircraft is maintained in an airworthy condition. This involves adhering to the detailed technical requirements set forth in the directive, which include precise measurements and adjustments to the antenna system.
Failure to comply with the provisions of AD/F27/38 can result in significant legal and operational consequences. Non-compliance may render the aircraft non-airworthy, which can lead to enforcement actions by the Civil Aviation Safety Authority (CASA). The potential consequences include fines, penalties, or other regulatory actions against the operator or owner of the aircraft. The specific penalties for non-compliance are determined by CASA and can vary depending on the severity and frequency of the breach, but they may include substantial financial penalties and potential grounding of the aircraft until the required modifications are completed.