Overview

The Civil Aviation Regulations 1998, specifically Part 39 - 105, outlines safety directives that are critical for ensuring the airworthiness of aircraft, including the Boeing 747 series aeroplanes. One such directive, AD/B747/74, addresses the issue of corrosion and cracking at the wing landing gear support beam outboard end fittings, which was identified as a potential safety hazard. This directive was introduced to mitigate the risk of structural failure in these critical components, which could lead to severe damage to control cables and hydraulic lines. The Federal Parliament enacted these regulations through the Civil Aviation Act 1988, with the overarching policy objective of enhancing aviation safety by ensuring that aircraft meet stringent airworthiness standards. Compliance with these directives is mandatory, with specific intervals for inspections and necessary actions if defects are found.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105 concerning the Civil Aviation Safety Authority Schedule of Airworthiness Directives, applies to Boeing 747 series aeroplanes, focusing on the wing landing gear support beam outboard end fittings. This regulation mandates a visual inspection for corrosion around the fitting lug bushings and an ultrasonic inspection for cracks on these landing gear beam outboard end fittings, in accordance with Boeing Service Bulletin 747-57-2244 Revision 2. Compliance with these directives is crucial for maintaining the airworthiness of the aircraft, as cracking initiated by corrosion can lead to significant damage, including separation of the beam's outboard end and potential damage to control cables and hydraulic lines. The inspections and subsequent actions must be carried out before specific service hour or time thresholds are exceeded, and rework or replacement must be completed before any further flight if cracks are detected. The regulation extends its application nationally and applies to all Boeing 747 models listed in the Requirement document, ensuring a standardised approach to maintaining safety and operational integrity across the industry.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 – 105, contain provisions that pertain to the airworthiness directives, particularly concerning Boeing 747 series aeroplanes. Section AD/B747/74 addresses the wing landing gear support beam outboard end fittings, which are critical components of the aircraft's structure. According to the directive, operators are required to visually inspect these fittings for corrosion and perform ultrasonic inspections for cracks, in accordance with Boeing Service Bulletin 747-57-2244 Revision 2 (section 11/89). This directive applies to all models of Boeing 747 as detailed in the requirement document. Compliance with these inspections is crucial to ensure the structural integrity of the aircraft. Operators of Boeing 747 aeroplanes must adhere to specific timelines for these inspections and subsequent actions. Prior to the aircraft reaching 30,000 hours of time in service, 8 years in service, or 31 November 1990, whichever comes first, an initial inspection must be completed. Following this initial inspection, inspections must be carried out at intervals not exceeding 18 calendar months until rework is completed (section 1). If any cracks are detected in the fittings, they must be reworked or replaced before the aircraft is flown again. In the event that only corrosion is found without cracks, an additional ultrasonic inspection must be performed within 6 calendar months, and any necessary rework must be completed before the aircraft exceeds one year of service (section 2). Failure to comply with these airworthiness directives can lead to serious consequences. The Civil Aviation Regulations 1998 impose obligations on operators to ensure that these inspections and necessary actions are performed in a timely manner. Non-compliance with these directives could result in the aircraft being deemed unairworthy, leading to potential grounding and legal ramifications. The safety of passengers and crew, as well as the overall integrity of the aircraft, depends on adherence to these stringent inspection and maintenance requirements. The regulations do not explicitly state penalties for non-compliance within this directive, but non-compliance could result in enforcement actions by the Civil Aviation Safety Authority, including fines and other penalties as outlined in the broader regulatory framework.