Overview

The Civil Aviation Regulations 1998, enacted by the Parliament of Australia, are integral to ensuring the safety and efficiency of civil aviation operations within the country. One particular legislative instrument, F2006B03040, pertains to Airworthiness Directives specifically targeting Boeing 747 series aeroplanes. This directive, AD/B747/138, was introduced to address a critical safety issue concerning the upper deck tension ties of Boeing 747 aircraft, specifically between Bulkheads 780 to 940. The directive mandates detailed visual inspections of these tension ties to prevent structural failure that could lead to catastrophic consequences, such as rapid depressurisation of the aircraft. Compliance with these inspections is mandatory to maintain airworthiness, with specific timelines and intervals provided for both unmodified and modified tension ties. This legislative measure underscores the Civil Aviation Safety Authority’s commitment to maintaining stringent safety standards in the aviation industry.

Scope and Application

The Civil Aviation Regulations 1998, as amended, under the Civil Aviation Act 1988, specifically in Part 39 - 105, apply to all operators of Boeing 747 Series aeroplanes within the Commonwealth of Australia. This regulation mandates detailed visual inspections of the upper deck tension ties between beam stations (BS) 780 to BS 940 to ensure the continued airworthiness of these aircraft. The specified inspections must be carried out in accordance with Boeing Service Bulletin 747-53-2371. This applies to all Boeing 747 aeroplanes, from line number 001 to 203 inclusive, and is directly linked to addressing safety concerns identified by the Federal Aviation Administration (FAA) in AD 94-13-06. The requirement is triggered by reports from six operators of 47 instances of cracked tension ties on 13 aircraft, highlighting the critical nature of these inspections. Failure to adhere to these mandates could compromise the structural integrity of the aircraft, potentially leading to rapid depressurisation. This regulation stipulates specific inspection intervals based on the modification status of the tension ties. Unmodified tension ties must be inspected within 1000 flights from 27 April 1995 if not performed in the last 2000 flights, with subsequent inspections occurring at intervals not exceeding 3000 flights. For modified tension ties, the initial inspection must occur before 10,000 flights post-modification, followed by reinspections at intervals not exceeding 6000 flights. This regulation applies nationally and is enforced by the Civil Aviation Safety Authority (CASA). It is comprehensive in its scope, covering all relevant operators and ensuring adherence to safety standards to prevent structural failures. The regulation does not specify any exclusions or exemptions, indicating its broad applicability across the industry.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 105, mandate that operators of Boeing 747 Series Aeroplanes perform detailed visual inspections of specific fuselage tension ties. Section 1 of AD/B747/138 requires operators to inspect the outboard ends of both unmodified and modified upper deck tension ties between Bulkheads 780 to 940. These inspections must be carried out in accordance with Boeing Service Bulletin 747-53-2371, which provides the necessary procedures and criteria for the inspections. The regulation references FAA AD 94-13-06 for additional guidance. Operators are required to comply with specific inspection intervals as outlined in the regulation. For unmodified tension ties, an initial inspection must be conducted if it has not been performed within the last 2000 flights, within 1000 flights from 27 April 1995, and subsequent reinspections must occur at intervals not exceeding 3000 flights. For modified tension ties, an initial inspection is required before 10000 flights post-modification, with reinspections at intervals not exceeding 6000 flights. Failure to adhere to these inspection requirements could compromise the structural integrity of the aircraft. Non-compliance with the AD/B747/138 may result in significant safety risks, as evidenced by reports from six operators of 47 cracked tension ties on 13 aircraft. Such failures can lead to rapid depressurisation of the aircraft, posing a serious threat to flight safety. The regulation does not explicitly state the penalties or consequences for non-compliance, but failure to adhere to airworthiness directives can lead to severe regulatory action, including grounding of the aircraft, fines, and other enforcement measures under the Civil Aviation Act 1988 and related regulations.