AD/B747/187 - Centre Wing Fuel Tank Scavenge Pump

Overview

The Civil Aviation Regulations 1998, enacted by the Commonwealth of Australia, is a comprehensive piece of legislation designed to regulate and ensure the safety of civil aviation within Australia. Part 39 - 105 of these regulations includes the Civil Aviation Safety Authority (CASA) Schedule of Airworthiness Directives, which aims to address specific safety concerns and ensure the continued airworthiness of aircraft. One such directive, AD/B747/187, pertains to Boeing 747 series aeroplanes, specifically addressing issues with the centre wing fuel tank scavenge pump. This directive was introduced to mitigate the risk of electrical failures and consequent fuel leakage or fire hazards within the aircraft's fuel system. The directive mandates a one-time inspection to identify the installed scavenge pump motor-impeller unit and requires either its replacement or deactivation if specific part numbers are identified, thus enhancing overall flight safety.

Scope and Application

The Civil Aviation Regulations 1998, under Part 39 - 105, specifically addresses the airworthiness directives for Boeing 747 series aeroplanes, with this particular directive focusing on the centre wing fuel tank scavenge pump. The directive applies to all Boeing 747 series aeroplanes with line positions ranging from 001 through 971 inclusive. The primary requirement is to perform a one-time inspection to ascertain the part number of the installed scavenge pump motor-impeller unit, as per Boeing Alert Service Bulletin (ASB) 747-28A2215 dated 14 May 1998. If the part number is either Boeing P/N 60B92403-5 or Lear Romec P/N RR24680, the scavenge pump must be replaced with a specified new or serviceable pump or deactivated, with continued operation permitted as outlined in the operator's approved Master Minimum Equipment List. Compliance with these directives must be achieved within 60 days from the effective date of the directive, before further flight after the inspection, and as of the directive's effective date. This directive effectively supersedes AD/B747/179 Amdt 1 (FAA AD 97-25-06) and responds to a reported incident of internal wiring damage, highlighting the importance of ensuring correct component installation to mitigate risks such as fuel leakage and electrical fires.

Key Provisions

The Civil Aviation Regulations 1998, Part 39 - 105, specifically addresses the airworthiness directives for Boeing 747 series aeroplanes, with AD/B747/187 concerning the centre wing fuel tank scavenge pump (10/98DM). This directive mandates a one-time inspection of the scavenge pump motor-impeller unit to determine its part number, either Boeing P/N 60B92403-5 or Lear Romec P/N RR24680 (section 1). If the part number matches either of these, the directive requires either the replacement of the scavenge pump with a specified part number or the deactivation of the scavenge pump, with the aeroplane then being allowed to operate under certain conditions (section 2). Additionally, it prohibits the installation of certain scavenge pumps on any aeroplane (section 3). Compliance with this directive must occur within 60 days of its effective date, before further flight after the inspection, and as of the effective date of the directive (section 4). The directive was made effective on 5 August 1998 and replaces the previous directive AD/B747/179 Amdt 1 (FAA AD 97-25-06). The Civil Aviation Regulations 1998 impose specific obligations on parties and entities governed by these airworthiness directives. Operators of Boeing 747 series aeroplanes must ensure that they conduct the required inspection to determine the part number of the scavenge pump motor-impeller unit. If the part number matches Boeing P/N 60B92403-5 or Lear Romec P/N RR24680, operators must replace the pump with a specified part number or deactivate it, ensuring compliance with the operator’s approved Master Minimum Equipment List. Furthermore, operators must ensure that certain scavenge pumps are not installed on any aeroplane. These obligations are to be fulfilled within the stipulated timeframes: within 60 days after the effective date of the directive, before further flight after the inspection, and as of the effective date of the directive. The Civil Aviation Regulations 1998 do not explicitly outline offences or penalties within the provided text for non-compliance with the airworthiness directives. However, failure to comply with these directives can result in severe consequences, including the risk of short circuiting and fuel leakage, which could lead to catastrophic outcomes such as fires or loss of aircraft control. The potential for such severe consequences underscores the importance of strict adherence to the directive’s requirements. While the specific penalties are not stated, non-compliance could lead to enforcement actions by the Civil Aviation Safety Authority, potentially including fines, suspension of operations, or other regulatory penalties as deemed appropriate by the authority.