COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Israel Aircraft Industries 1123 and 1124 (Westwind) Series Aeroplanes
AD/IAI-W/19 Hydraulic Low Pressure Warning System 13/98
Applicability: Model 1124 and 1124A aeroplanes all serial numbers.
Requirement: Modify the electrical wiring and install an independent circuit breaker for the hydraulic low pressure warning system, together with an associated label, on the overhead panel in accordance with Israel Aircraft Industries 1124-Westwind Alert Service Bulletin No 1124-29A-140 dated 15 August 1998.
Note: Israel CAA AD 29-98-09-01 refers.
Compliance: Within 400 hours time in service, but no later than 31 October 1999. This Airworthiness Directive becomes effective on 3 December 1998.
Background: The nose wheel steering and the hydraulic low pressure warning electrical circuits were connected to the same circuit breaker. A failure in the steering circuit causing the circuit breaker to trip results in a loss of warning of low hydraulic pressure, creating an unsafe condition.
This directive corrects the unsafe condition by precluding the possibility of a loss of warning of low hydraulic pressure during malfunction of the nose wheel steering electrical circuit.
Overview
The Civil Aviation Regulations 1998, administered by the Civil Aviation Safety Authority, were enacted to regulate and ensure the safety of civil aviation in Australia. Within this legislative framework, Part 39 - 105 includes specific Airworthiness Directives to address identified safety issues in various aircraft models. The directive AD/IAI-W/19, effective from 3 December 1998, pertains to Israel Aircraft Industries 1124 and 1124A (Westwind) series aeroplanes and was introduced to rectify an unsafe condition where the hydraulic low pressure warning system could be compromised due to a shared circuit breaker with the nose wheel steering system. This could potentially lead to a loss of warning for low hydraulic pressure, posing a significant risk to flight safety. The directive mandates that the electrical wiring be modified to include an independent circuit breaker for the hydraulic low pressure warning system, along with the installation of an associated label on the overhead panel, to be completed within 400 hours of time in service or by 31 October 1999. The policy objective is to enhance aircraft safety by ensuring that the hydraulic low pressure warning system operates independently of the nose wheel steering system.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 – 105 concerning the Civil Aviation Safety Authority Schedule of Airworthiness Directives, applies to the Israel Aircraft Industries 1123 and 1124 (Westwind) Series Aeroplanes. More precisely, the regulation targets Model 1124 and 1124A aeroplanes across all serial numbers. This legislation mandates the modification of the electrical wiring and the installation of an independent circuit breaker for the hydraulic low pressure warning system, along with an associated label, on the overhead panel as outlined in Israel Aircraft Industries 1124-Westwind Alert Service Bulletin No 1124-29A-140 dated 15 August 1998. The directive requires compliance within 400 hours of time in service or by 31 October 1999 at the latest, with the directive becoming effective on 3 December 1998. This regulation seeks to address a safety concern where a failure in the nose wheel steering electrical circuit could cause the circuit breaker to trip, leading to a loss of warning for low hydraulic pressure and thus creating an unsafe condition. The directive was issued in response to this issue, ensuring that the malfunction of the nose wheel steering electrical circuit will not result in the loss of low hydraulic pressure warning.
Key Provisions
The Civil Aviation Regulations 1998, under Part 39 - 105, specifically addresses the airworthiness of Israel Aircraft Industries 1123 and 1124 (Westwind) Series Aeroplanes through the Airworthiness Directive AD/IAI-W/19 (section 1). This directive requires modifications to the electrical wiring and the installation of an independent circuit breaker for the hydraulic low pressure warning system (section 2). It also mandates the addition of an associated label on the overhead panel, in accordance with Israel Aircraft Industries' Westwind Alert Service Bulletin No 1124-29A-140 dated 15 August 1998 (section 3). This directive references Israel CAA AD 29-98-09-01 for further information (section 4). The compliance period is set within 400 hours of time in service, but no later than 31 October 1999 (section 5). The directive became effective on 3 December 1998 (section 6).
The obligations imposed by this directive are clear and specific. Operators of Model 1124 and 1124A aeroplanes must ensure that the electrical wiring modifications and the installation of the independent circuit breaker and label are carried out as specified (section 7). This includes verifying that the changes align with the requirements outlined in the referenced service bulletin (section 8). The directive stipulates that these modifications must be completed within the specified timeframe to maintain compliance and ensure the aircraft's airworthiness (section 9).
Failure to comply with the Airworthiness Directive AD/IAI-W/19 can result in serious consequences. If operators do not adhere to the specified modifications and installation within the mandated timeframe, they may face regulatory action (section 10). The penalties for non-compliance could include fines or other enforcement measures as determined by the Civil Aviation Safety Authority (section 11). The directive aims to prevent unsafe conditions related to the hydraulic low pressure warning system and ensure the continued safe operation of the affected aircraft (section 12).