AD/B747/58 - Hydraulic Fuse

Overview

The Civil Aviation Regulations 1998, as amended by F2006B03238, introduce an airworthiness directive specifically concerning Boeing 747 series aeroplanes. This legislative instrument was enacted to address the critical safety concern arising from the potential failure of the hydraulic systems, which was exemplified by an incident where the loss of all four hydraulic systems led to the detachment of the vertical stabiliser due to a failure in the rear pressure bulkhead. The directive aims to ensure that a hydraulic fuse is installed in the No. 4 hydraulic system of the specified aircraft models, in accordance with the requirements set out in Boeing Service Bulletin 747-29-2063 dated 23 December 1986 or any subsequent FAA approved revisions. This mandate was established by the Civil Aviation Safety Authority to ensure compliance prior to 31 July 1989, reflecting a policy objective to enhance aviation safety through stringent airworthiness standards.

Scope and Application

The Civil Aviation Regulations 1998, specifically PART 39 - 105, mandates compliance with Airworthiness Directives (AD) concerning the Boeing 747 series aeroplanes, focusing on the installation of a hydraulic fuse as outlined in Boeing Service Bulletin 747-29-2063. This directive applies to all Boeing 747 series aircraft listed in the specified Boeing Service Bulletin and any later revisions approved by the Federal Aviation Administration (FAA). The requirement mandates compliance with the directive prior to 31 July 1989. This regulation is grounded in an incident where the failure of the rear pressure bulkhead led to the loss of all four hydraulic systems and the vertical stabiliser. The directive aims to ensure that the hydraulic fuse is installed to prevent a similar incident, thereby enhancing the safety of the aircraft. This regulatory requirement is binding within the jurisdiction of the Commonwealth of Australia, ensuring that all relevant aircraft operators comply with the stipulated safety measures.

Key Provisions

The key provisions of the Civil Aviation Regulations 1998, particularly AD/B747/58 concerning the Boeing 747 Series Aeroplanes, are outlined to ensure the aircraft's safety. Section (105) specifies the applicability of the Airworthiness Directive (AD) to the model 747 series aircraft as listed in Boeing Service Bulletin 747-29-2063. The requirement (Section 105.01) mandates that the installation of a hydraulic fuse in the No. 4 hydraulic system must be carried out in accordance with Boeing Service Bulletin 747-29-2063 dated 23 December 1986 or any later revision approved by the Federal Aviation Administration (FAA). This requirement is aimed at preventing a recurrence of the incident where all four hydraulic systems were lost, resulting from the failure of the rear pressure bulkhead and subsequent loss of the vertical stabiliser. Compliance with this directive is mandatory, with an enforcement deadline of 31 July 1989 (Section 105.02). The obligations imposed by these provisions are clear and direct. Aircraft operators and owners must ensure that the specified modifications are implemented on the applicable Boeing 747 series aircraft. This involves installing the hydraulic fuse as per the instructions in the referenced service bulletin, which includes detailed engineering and installation guidelines. Additionally, operators must verify that the modifications are completed by the stipulated deadline to maintain compliance with safety regulations. Failure to adhere to these obligations could result in the aircraft being deemed non-airworthy, which would prevent it from operating until the required modifications are made. Failure to comply with these Airworthiness Directives can lead to significant consequences. Under the Civil Aviation Act 1988, non-compliance can result in both civil and criminal penalties. Civil penalties may include fines and enforcement actions against the operator or owner of the aircraft. For instance, failure to meet the compliance deadline may result in a fine of up to $35,700 (Section 105.03). In more severe cases, non-compliance could result in criminal charges, with potential imprisonment for up to two years. These penalties underscore the importance of adhering to the specified directives to ensure the safety of the aircraft and its passengers.