AD/F50/47 - Nose Landing Gear Retraction Mechanism

Overview

The Civil Aviation Regulations 1998, as amended by the Legislative instrument F2006B09874, introduce specific Airworthiness Directives to ensure the safety of aircraft operations. One such directive, AD/F50/47, pertains to Fokker F50 (F27 Mk 50) Series Aeroplanes and addresses issues with the nose landing gear retraction mechanism. Enacted by the Commonwealth of Australia, this legislation aims to rectify a problem identified during full-scale fatigue testing where cracks were found near a lightening hole in the nose landing gear link assembly. The policy objective is to enhance the safety and durability of these aircraft by mandating the replacement of the current retraction link assembly with a reinforced unit, to be carried out before the component exceeds 12,000 pressurisation cycles. This measure is intended to prevent potential structural failures that could compromise flight safety. The directive applies to specific serial numbers of Fokker F50 aircraft and requires compliance with the technical requirements outlined in RLD AD 90-057, dated 23 May 1990, as referenced in Fokker Service Bulletin F50-32-004, dated 17 April 1990. This legislative instrument is a critical component in the ongoing efforts to maintain high safety standards within the civil aviation sector, ensuring that aircraft are maintained in a safe and airworthy condition.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 – 105, applies to the Fokker F50 (F27 Mk 50) Series Aeroplanes, with the focus on ensuring the airworthiness of these aircraft models. The legislation mandates compliance with Airworthiness Directive AD/F50/47 concerning the nose landing gear retraction mechanism for Fokker F50 aircraft with serial numbers ranging from 20103 to 20108 inclusive, and from 20110 to 20131 inclusive. This directive applies to all persons or entities operating these specific Fokker F50 aircraft within the Commonwealth of Australia, ensuring that the modifications and inspections are conducted in accordance with the technical requirements outlined in RLD AD 90-057 dated 23 May 1990. Compliance with this directive must be achieved prior to exceeding 12,000 pressurisation cycles, highlighting the critical nature of the modifications for the safety and integrity of the nose landing gear system. The directive references Fokker Service Bulletin F50-32-004 dated 17 April 1990, which provides further technical guidance and details on the implementation of the required changes.

Key Provisions

The main operative sections of the Civil Aviation Regulations 1998, specifically Part 39 - 105, mandate adherence to Airworthiness Directives (AD) for certain Fokker F50 aircraft models. Section 39.105 outlines the applicability of AD/F50/47, which pertains to nose landing gear retraction mechanisms for Fokker F50 aeroplanes with specific serial numbers (section 39.105(1)). The requirement for compliance is detailed in section 39.105(2), which mandates action in accordance with the Technical Requirements of RLD AD 90-057, dated 23 May 1990. This directive references Fokker Service Bulletin F50-32-004, dated 17 April 1990, for further guidance (section 39.105(3)). Compliance must be achieved prior to the aircraft exceeding 12,000 pressurisation cycles (section 39.105(4)). The Civil Aviation Regulations impose specific obligations on the operators and maintainers of Fokker F50 aircraft within the serial number ranges specified. These parties are required to replace the nose landing gear link assembly with a reinforced unit as per the technical requirements outlined in RLD AD 90-057. This is necessary to mitigate the risk of cracks identified during fatigue testing. Operators must ensure that the modification is completed before the aircraft reaches 12,000 pressurisation cycles, thereby maintaining the airworthiness of the aircraft (section 39.105(4)). Compliance with this directive involves following the detailed instructions provided in Fokker Service Bulletin F50-32-004. Failure to comply with the requirements of AD/F50/47 can result in serious legal and safety consequences. The Civil Aviation Regulations do not explicitly state penalties for non-compliance in this context, but non-compliance can lead to aircraft being deemed unairworthy. This could result in grounding of the aircraft, potential criminal charges for the operators, and significant civil liabilities. The severity of penalties can vary based on the circumstances and the discretion of the Civil Aviation Safety Authority, but the potential for severe consequences underscores the importance of strict adherence to these directives (section 39.105(5)). In summary, the Civil Aviation Regulations mandate that Fokker F50 aircraft within specific serial number ranges must comply with AD/F50/47 to replace the nose landing gear retraction link assembly before exceeding 12,000 pressurisation cycles. Operators and maintainers are required to follow the technical guidelines provided in RLD AD 90-057 and Fokker Service Bulletin F50-32-004. Non-compliance can lead to serious civil and criminal repercussions, highlighting the critical nature of these safety directives.