AD/BAe 146/72 - Fire Protection and Smoke Detection - Freight Compartment

Overview

The Civil Aviation Regulations 1998, specifically within Part 39 - 105, incorporates Airworthiness Directives aimed at ensuring the safety and airworthiness of aircraft. One such directive, AD/BAe 146/72 issued in 1999, pertains to the British Aerospace BAe 146 Series aeroplanes. This directive addresses the issue of potential malfunctions in smoke detectors installed in the freight compartment of specific BAe 146 models. The problem identified was that the operation of the flight deck smoke detection test switch could erroneously indicate that the smoke detectors were serviceable, even when the detector's light source filament was actually blown. This could pose a significant risk to the safety of the aircraft and its occupants. The objective of this directive is to ensure that the smoke detectors are tested for serviceability in accordance with specified procedures, thus maintaining the integrity of the aircraft's fire protection and smoke detection systems. The directive is enacted by the Civil Aviation Safety Authority (CASA), ensuring compliance with stringent safety standards.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, mandates the applicability of the Airworthiness Directive AD/BAe 146/72, which focuses on fire protection and smoke detection in the freight compartment of British Aerospace BAe 146 series aeroplanes. This directive applies to all BAe 146 series aeroplanes equipped with specific L’Hotellier smoke detectors. Notably, these smoke detectors are installed in various BAe 146-100, 146-200, and 146-300 series aircraft, as well as to BAe 146 Series 200 with Mod HCM50201C embodied and BAe 146 Series 300 with Mod HCM50214C embodied. The directive requires that the smoke detectors be tested for serviceability according to British Aerospace, Regional Aircraft Limited Service Bulletin SB.26-A38 Revision 1 dated 20 October 1998, which has been classified as mandatory by the UK's Civil Aviation Authority. Compliance with this directive necessitates that these tests be conducted prior to 18 December 1998 and subsequently at intervals not exceeding 48 hours. The incorporation of Mod No HCM56094A, B, and C (SB 26-38-56094A, B, and C) terminates the requirement for these repetitive inspections, and the Airworthiness Directive became effective on 16 December 1998.

Key Provisions

The Civil Aviation Regulations 1998, particularly Part 39 - 105, under the Civil Aviation Safety Authority (CASA) Schedule of Airworthiness Directives, outlines specific requirements for British Aerospace (BAe) 146 Series aeroplanes. The directive AD/BAe 146/72 pertains to fire protection and smoke detection in the freight compartment, dated 1 January 1999. This directive applies to all BAe 146 series aeroplanes equipped with specific L’Hotellier smoke detectors, including those with part numbers FR2113, FR2121, FR2213, and FR2226. The directive also references particular model constructor numbers for the BAe 146-100, 200, and 300 series aircraft. The directive requires that the smoke detectors be tested for serviceability in accordance with British Aerospace, Regional Aircraft Limited, Service Bulletin SB.26-A38 Revision 1 dated 20 October 1998. This testing must be carried out prior to 18 December 1998 and subsequently at intervals not exceeding 48 hours. Compliance with the directive also involves incorporating Modification Numbers HCM56094A, B, and C (SB 26-38-56094A, B, and C), which serve as terminating actions for these repetitive inspections. The directive became effective on 16 December 1998. Operators of the BAe 146 series aeroplanes must ensure that their aircraft meet the specified requirements to maintain airworthiness. They are obligated to perform the smoke detector tests as mandated and incorporate the relevant modifications. Failure to comply with these directives can result in significant safety risks, as the directive was issued in response to issues found during in-service troubleshooting where the flight deck smoke detection test switch indicated serviceability despite a blown detector light source filament. Failure to adhere to the provisions of this Airworthiness Directive may lead to serious consequences. Non-compliance could potentially result in the aeroplane not meeting the required safety standards, which could lead to grounding or other regulatory actions by CASA. While specific penalties are not detailed in the directive, violations of airworthiness directives can generally result in substantial fines and enforcement actions, including potential criminal charges for serious breaches that endanger safety.