AD/HS 125/151 Amdt 1 - APU Fuel Feed Hose Assemblies

Overview

The Civil Aviation Regulations 1998 (Cth), as amended through the Legislative instrument F2006B10432, were enacted to enhance the safety standards and regulatory framework governing civil aviation in Australia. This particular legislative instrument, issued under the authority of the Civil Aviation Act 1988 (Cth), aims to address a specific safety issue identified with the Auxiliary Power Unit (APU) fuel feed hose assemblies in the British Aerospace BAe 125 Series Aeroplanes, particularly post Mod 259722C where the Turbomach APU was introduced. The problem targeted by this amendment is the risk of in-flight fires due to complete failure of the APU hoses, which can occur if they sustain heat damage from impingement of hot bleed air leaking from adjacent pneumatic components. The policy objective behind this directive is to mitigate these risks by mandating inspections and replacements of the fuel feed hose assemblies, thereby ensuring continued airworthiness and safety of the affected aircraft.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, governs the safety of civil aviation operations in Australia and applies to all aircraft registered in the country. The legislative instrument AD/HS 125/151 Amendment 1 is a directive concerning the airworthiness of British Aerospace BAe 125 Series Aeroplanes, specifically the series 1000A, 1000B, and Hawker 1000 aircraft post modification 259722C, which includes the introduction of the Turbomach APU. The directive mandates the inspection and replacement of the APU fuel feed hose assembly to mitigate the risk of heat damage and potential in-flight fire. Compliance with the inspection requirement is mandatory unless previously completed, with the initial effective date set for 31 May 1995, and thereafter as per the manufacturer's maintenance schedules. The replacement requirement must be fulfilled within 200 flight hours, with an effective date of 5 December 1995, and compliance with this requirement terminates the need for further inspections. The amendment became effective on 5 December 1996, reinforcing the need for ongoing airworthiness and safety in civil aviation operations.

Key Provisions

The main operative sections of this Civil Aviation Regulation require inspections and replacements of the Auxiliary Power Unit (APU) fuel feed hose assemblies on specific BAe 125 series aeroplanes. Section 1 mandates that the APU fuel feed hose assembly be inspected in accordance with Hawker Raytheon Corporate Jets Mandatory Inspection Service Bulletin SB 49-44 Revision 1 (AD/HS 125/151). This inspection is required unless it has already been completed, with an effective date of 31 May 1995, and must then be performed at intervals specified in the manufacturer's maintenance schedules. Section 2 requires the replacement of the vinyl conduit on the APU fuel feed hose assembly with a convoluted PTFE tube, in accordance with Hawker Service Bulletin SB.49-47-25A825A (Modification No. 25A825A). This replacement must be completed within 200 flight hours, with an effective date of 5 December 1995. The obligations imposed by this regulation are clear and specific. Aircraft operators must ensure that the required inspections and modifications to the APU fuel feed hose assemblies are completed according to the specified timelines and procedures. Failure to comply with these requirements could result in serious safety risks, including the possibility of an in-flight fire due to complete failure of the APU hoses. Breach of these regulations can lead to significant consequences. Although the specific penalties are not detailed in the excerpt, violations of civil aviation regulations can generally result in enforcement actions by the Civil Aviation Safety Authority (CASA). These actions may include fines, suspension or revocation of air operator certificates, and other administrative penalties. In severe cases, non-compliance could also result in criminal charges, potentially leading to imprisonment, depending on the severity and impact of the breach on aviation safety. The effective date of these requirements is crucial for compliance. The initial inspection mandate became effective on 31 May 1995, and the replacement requirement took effect on 5 December 1995. The entire amendment became effective on 5 December 1996, providing a clear timeline for operators to adhere to these safety measures. Compliance with these provisions is essential to mitigate the risk of in-flight fires caused by damage to the APU fuel feed hoses.