COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
British Aerospace BAe 125 Series Aeroplanes
AD/HS 125/112 Water System 11/90
Applicability: Model 125-600A, 125-700A, and 125-800A series equipped with a cabin interior and aft lavatory water system installed in accordance with STC SA 2271 SW.
Requirement: Drain all water from the aft lavatory water system reservoir, deactivate the water system pressure pump by pulling the circuit breaker located beneath the vanity in the aft lavatory, and install a tie wrap on the circuit beaker to prevent it from being reset.
Note 1: FAA AD 90-08-07 Amdt 39-6600 refers.
Note 2: Reactivation will be dependent upon the design of a modification that is acceptable to the Authority.
Compliance: Prior to the issue of a Certificate of Airworthiness.
Background: This Airworthiness Directive is raised in response to a FAA report of an aft lavatory water system leak, which caused the aileron control system to jam due to the resulting ice formation on the aileron control cables and fairleads.
Overview
The Civil Aviation Regulations 1998, under PART 39 - 105, introduce a schedule of airworthiness directives to ensure the safety of aircraft in Australian airspace. One such directive, AD/HS 125/112, pertains specifically to the British Aerospace BAe 125 Series Aeroplanes, targeting the water system of models 125-600A, 125-700A, and 125-800A equipped with a cabin interior and an aft lavatory water system. This directive was enacted to address a safety issue identified by the Federal Aviation Administration (FAA) involving leaks in the aft lavatory water system that led to ice formation on the aileron control cables and fairleads, causing aileron control system jamming. The Australian Civil Aviation Safety Authority (CASA) mandates that these safety measures be implemented to ensure the airworthiness of the specified aircraft, thereby preventing potential hazards that could compromise flight safety.
Scope and Application
The Civil Aviation Regulations 1998, under PART 39 - 105, mandate the application of airworthiness directives by the Civil Aviation Safety Authority (CASA) for the maintenance of safety standards in civil aviation. Specifically, AD/HS 125/112 pertains to British Aerospace BAe 125 Series aeroplanes, namely the 125-600A, 125-700A, and 125-800A models equipped with a cabin interior and aft lavatory water system installed in accordance with STC SA 2271 SW. This regulation applies nationally across Australia, governed under the Commonwealth jurisdiction, ensuring compliance with safety standards set by CASA. The directive requires the deactivation of the water system pressure pump and the installation of a tie wrap on the circuit breaker to prevent reactivation until a modification acceptable to CASA is implemented. Compliance is mandatory prior to the issuance of a Certificate of Airworthiness. This regulation extends its application by referencing FAA AD 90-08-07 Amdt 39-6600 and includes a specific requirement to address a reported issue of aft lavatory water system leaks that led to aileron control system jamming due to ice formation on the aileron control cables and fairleads.
Key Provisions
The Civil Aviation Regulations 1998 (Regulations) under Part 39, specifically within Section 105, mandates the observance of Airworthiness Directives (ADs) for certain aircraft models. AD/HS 125/112 pertains to the British Aerospace BAe 125 Series Aeroplanes, more specifically models 125-600A, 125-700A, and 125-800A, which are equipped with a cabin interior and an aft lavatory water system installed as per STC SA 2271 SW. This AD is a response to a reported issue where a leak in the aft lavatory water system resulted in ice formation on the aileron control cables and fairleads, subsequently causing the aileron control system to jam. The directive outlines specific actions that must be taken to prevent such occurrences in the future.
Under Section 105 of the Regulations, the AD/HS 125/112 requires operators of the specified BAe 125 series aeroplanes to drain all water from the aft lavatory water system reservoir. Additionally, the water system pressure pump must be deactivated by pulling the circuit breaker located beneath the vanity in the aft lavatory. To ensure the pump remains deactivated, a tie wrap must be installed on the circuit breaker to prevent it from being reset. These actions are imperative to mitigate the risk of ice formation and subsequent system malfunction. Compliance with these directives is mandatory and must be achieved prior to the issuance of a Certificate of Airworthiness.
The AD imposes several obligations on the parties it governs. Operators must meticulously follow the outlined procedures to ensure the safety of the aircraft and its occupants. This includes not only the physical actions of draining the water system and deactivating the pump but also the procedural step of securing the circuit breaker with a tie wrap. Failure to comply with these directives could result in severe safety risks, including potential system failures and compromised flight safety. Operators must also keep records of compliance and be prepared to demonstrate adherence to the AD requirements during inspections.
Failure to comply with AD/HS 125/112 can result in significant civil and criminal consequences. Non-compliance with ADs is an offence under the Civil Aviation Act 1988, and penalties can include substantial fines. The maximum penalty for contravening these regulations can reach up to $21,000 for individuals and higher for corporations, depending on the severity of the breach. Additionally, non-compliance can lead to the grounding of the aircraft until the necessary actions are taken, potentially causing significant operational disruptions and financial losses. Thus, adherence to these directives is not merely a regulatory requirement but a critical aspect of ensuring safe aviation practices.