AD/B737/47 - Left Engine Fuel Feed Tube

Overview

The Civil Aviation Regulations 1998, specifically Part 39 - 105 Civil Aviation Safety Authority Schedule of Airworthiness Directives, address the safety concerns associated with the left engine fuel feed tube in Boeing 737-300 and 737-400 series aeroplanes. This legislation was enacted to mitigate the risk of fuel leakage and potential engine strut fire hazards due to chafing of the left engine fuel feed tube in the wing/strut area, as reported to the Federal Aviation Administration (FAA). The objective of this directive is to ensure compliance with safety standards by requiring inspections, replacements, and clearance verifications as outlined in the specified Boeing Service Bulletins. Compliance with these directives is mandatory and must be achieved by specified dates to maintain airworthiness and safety standards. The Civil Aviation Regulations 1998, as amended, are overseen by the Australian Government and are designed to enhance aviation safety through the implementation of airworthiness directives. The policy objective behind this particular directive is to prevent potential fire hazards and ensure the structural integrity of the left engine fuel feed tube, thereby safeguarding the operational safety of Boeing 737-300 and 737-400 series aircraft.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, pertains to airworthiness directives issued by the Civil Aviation Safety Authority (CASA) and applies to Boeing 737-300 and 737-400 series aircraft as referenced in Boeing Service Bulletin 737-28-1084. The regulation mandates certain actions to address the risk of fuel leakage and potential fire hazards arising from chafing of the left engine fuel feed tube. Operators of the specified Boeing 737 models must either inspect the fuel feed tube assembly for proper clearance and chafing, or replace the assembly according to the specified Boeing service bulletins. The compliance deadlines outlined in the directive necessitate corrective action prior to specific dates in 1991. The geographic reach of this regulation is national, applying across Australia in accordance with federal civil aviation regulations. There are no stated exclusions or exemptions in this directive, and the application extends through the enforcement of CASA’s authority under the Civil Aviation Act 1988.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 105, includes an Airworthiness Directive (AD) concerning Boeing 737 Series Aeroplanes. This directive, AD/B737/47, pertains to the left engine fuel feed tube and is applicable to Model 737-300 and 737-400 series aeroplanes, as listed in Boeing Service Bulletin 737-28-1084. The directive requires that unless a specific action has already been completed, one of three actions must be taken regarding the left engine fuel feed tube assembly. Firstly, it must be inspected for proper clearance and chafing as per Boeing Service Bulletin 737-28-1055 Revision 1 (Section 1). Secondly, the left engine fuel feed tube assembly must be replaced in accordance with Boeing Service Bulletin 737-28-1084, and the minimum clearance between the support structure and the fuel tube must be verified using Boeing Service Bulletin 737-28-1055 Revision 1 (Section 2). Thirdly, the left engine fuel feed tube assembly must be replaced following Boeing Service Bulletin 737-28-1084, and the minimum clearance must be verified as per Boeing Service Bulletin 737-28-1084 Revision 1 (Section 3). These compliance actions are crucial to address reports of chafing in the left engine fuel feed tube, which could lead to fuel leakage and potentially cause an engine strut fire hazard. Compliance with this AD is mandatory for the specified models of Boeing 737 aeroplanes. Operators of these aircraft must ensure that the required actions are completed by the specified deadlines: inspections must be performed prior to 31 January 1991 (Section 1), the first replacement action must be completed prior to 30 April 1991 (Section 2), and the second replacement action must also be completed prior to 30 April 1991 (Section 3). This directive underscores the importance of timely action to maintain the airworthiness of these aeroplanes. Failure to comply with the AD may result in significant consequences. The regulations impose strict obligations on the operators to ensure that the left engine fuel feed tube is inspected and, where necessary, replaced according to the specified Boeing Service Bulletins. Non-compliance with these requirements can lead to severe civil or criminal penalties, which may include fines, sanctions, or even grounding of the aircraft. The AD references FAA AD 90-15-03 Amdt 39-6650, indicating a coordinated effort between Australian and international aviation authorities to ensure the safety of the aviation industry. The maximum penalties for breaches of these regulations are not explicitly stated in the text, but they could potentially include substantial fines and imprisonment, depending on the severity of the non-compliance.