AD/B737/158 Amdt 1 - Fuel System Wiring Shielding and Separation

Overview

The Airworthiness Directive (AD) AD/B737/158, enacted in 2002 by the Civil Aviation Safety Authority (CASA), addresses a critical safety concern related to the wiring systems of Boeing 737 Series Aeroplanes. This directive was introduced to rectify an unsafe condition identified in the fuel system wiring, specifically its routing to the fuel tanks, which posed a risk due to inadequate shielding and separation from adjacent wiring. The unsafe condition was identified through accident investigations and testing results, leading to the revocation of the previous directive and the introduction of this amendment to provide alternative methods of compliance. The objective of the AD is to ensure the safety of the aircraft by mandating specific actions to mitigate the identified risk, thus enhancing overall aviation safety standards.

Scope and Application

This Airworthiness Directive (AD) applies to all Boeing 737 series aeroplanes, specifically models 737-100, -200, -300, -400, and -500. The AD is issued under subregulation 39.1(1) of the Civil Aviation Regulations 1998 and mandates that shielding and separation of the fuel system wiring routed to the fuel tanks must be provided to prevent it from coming into contact with adjacent wiring. Compliance with the directive is mandatory, with the requirement that the specified action must be taken before 10 March 2003. The directive can be complied with by following either an approved method by the Civil Aviation Safety Authority, or by applying a Federal Aviation Administration Supplemental Type Certificate (STC). The directive does not specify exclusions or exemptions but provides alternative compliance methods to ensure the safety of the aircraft in question. This AD is applicable nationally within the Commonwealth of Australia and was issued by a delegate of the Civil Aviation Safety Authority, with the amendment becoming effective on 13 June 2002.

Key Provisions

The Airworthiness Directive (AD) AD/B737/158 Amdt 1, issued under subregulation 39.1 (1) of CAR 1998, applies to all Model 737-100, -200, -300, -400, and -500 series aeroplanes (section 1). The directive mandates that the action outlined in the requirement section must be taken to address an unsafe condition (section 2). This action involves providing shielding and separation of the fuel system wiring routed to the fuel tanks from adjacent wiring (section 2). The directive allows for compliance through either a method approved by the Section Head, Systems; Certification Standards Branch; Aviation Standards Division; Civil Aviation Safety Authority (section 2(a)), or through two specific FAA Supplemental Type Certificates (STCs) – ST00847SE dated 6 October 2000 and ST00127BO dated 5 September 2000 (sections 2(b) and 2(c)). The compliance deadline is before 10 March 2003 (section 3). This Amendment to the AD became effective on 13 June 2002. The AD imposes several obligations on the parties it governs. Primarily, it requires aircraft operators and owners to ensure that the specified shielding and separation of fuel system wiring is implemented in their Boeing 737 Series Aeroplanes. This involves either obtaining approval for an alternative method from the Civil Aviation Safety Authority or adhering to the FAA STCs mentioned in the AD (section 2). Operators must submit applications for alternative methods to the appropriate Engineering Support Branch office responsible for the applicant (Note 3). Furthermore, the AD references other relevant documents, such as FAA AD 99-03-04 Amdt 39-11018, FAA Transport Airplane Directorate Letter 130S-00-0626, and FAA Transport Airplane Directorate Letter 130S-00-0632, which provide further guidance and context (Notes 1, 2, and 5). Failure to comply with the AD may result in significant legal consequences. Although the AD itself does not explicitly state penalties for non-compliance, violations of ADs can lead to enforcement actions under the Civil Aviation Act 1988 and Civil Aviation Regulations 1988 (CAR). Non-compliance may result in enforcement actions such as fines, suspension or revocation of aircraft certificates, and potential criminal charges under sections 67 and 68 of the Act, which pertain to unsafe aircraft and reckless behaviour, respectively. The maximum penalties for these offences can include substantial fines and imprisonment, reflecting the seriousness of ensuring aircraft safety. Additionally, the AD references other documents that may impose their own compliance requirements and consequences. For example, the FAA STCs mentioned in the AD may have specific installation and compliance criteria, and failure to meet these criteria could lead to additional regulatory actions by the FAA or other relevant authorities. It is crucial for operators to thoroughly review and comply with all referenced documents to avoid any potential legal repercussions. In conclusion, the AD AD/B737/158 Amdt 1 requires specific shielding and separation measures for fuel system wiring in Boeing 737 Series Aeroplanes, with compliance mandated by a specified deadline. Failure to adhere to these requirements can result in significant legal and regulatory consequences, including potential fines, suspension or revocation of aircraft certificates, and criminal charges. It is essential for operators to meticulously follow the AD and all referenced documents to ensure compliance and maintain the highest safety standards.