COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Airtractor AT-300, 400 and 500 Series Aeroplanes
AD/AT/18 Parking Brake Valve 5/97
Applicability: All model AT-250, AT-300, AT-301, AT-302, AT-400, AT-400A, AT-401, AT-402,
AT-501 and AT-502 series aircraft not fitted with Scott P/N 4500A-2 parking brake valve.
Requirement: Unless previously carried out, replace Gerdes P/N A-850-5 or Cleveland P/N 60-9, as applicable, parking brake valve with Scott P/N 4500A-2 parking brake valve in accordance with Snow Engineering Co. Service Letter #76, dated December 12, 1988.
Note: FAA AD 96-24-08 Amdt 39-9833 refers.
Compliance: At next scheduled maintenance release issue after 31 May 1997, or by 31 December 1997, whichever occurs first.
This Airworthiness Directive becomes effective on 24 April 1997.
Background: Advice has been received that during flight the parking brake valve lever can slip from the OFF to the ON position and has caused several aircraft to overturn when landing.
Overview
The Civil Aviation Regulations 1998, administered by the Civil Aviation Safety Authority (CASA), were enacted to ensure the safety of civil aviation within Australia. One of the amendments made under this regulation is AD/AT/18, introduced to address a safety issue identified in the Airtractor AT-300, 400, and 500 Series Aeroplanes. This particular directive aims to rectify a problem where the parking brake valve lever can inadvertently slip from the OFF to the ON position during flight, potentially leading to aircraft overturning upon landing. The policy objective behind this directive is to ensure the safety and reliability of the aircraft by mandating the replacement of specific parking brake valves to prevent such incidents.
The directive applies to all model AT-250, AT-300, AT-301, AT-302, AT-400, AT-400A, AT-401, AT-402, AT-501, and AT-502 series aircraft not already fitted with the Scott P/N 4500A-2 parking brake valve. The requirement is to replace the existing Gerdes or Cleveland parking brake valves with the specified Scott valve in accordance with Snow Engineering Co. Service Letter #76, dated December 12, 1988. Compliance with this directive must be achieved by the next scheduled maintenance release issue after 31 May 1997 or by 31 December 1997, whichever occurs first. This Airworthiness Directive became effective on 24 April 1997, reflecting the urgency and importance of addressing the identified safety risk.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 105 pertaining to Airworthiness Directives, applies to all Airtractor AT-300, 400, and 500 series aeroplanes that are not equipped with the Scott P/N 4500A-2 parking brake valve. This regulation is enforced under the Commonwealth of Australia and affects all model AT-250, AT-300, AT-301, AT-302, AT-400, AT-400A, AT-401, AT-402, AT-501, and AT-502 series aircraft that do not have the specified parking brake valve installed. The requirement mandates that unless previously carried out, the Gerdes P/N A-850-5 or Cleveland P/N 60-9 parking brake valve must be replaced with the Scott P/N 4500A-2 parking brake valve in compliance with Snow Engineering Co. Service Letter #76, dated December 12, 1988. The directive became effective on 24 April 1997, with compliance expected at the next scheduled maintenance release issue after 31 May 1997, or by 31 December 1997, whichever comes first. This directive was issued in response to incidents where the parking brake valve lever slipped from the OFF to the ON position during flight, resulting in several aircraft overturning upon landing.
Key Provisions
The Civil Aviation Regulations 1998, specifically Part 39 - 105, addresses the safety requirements for certain Airtractor aeroplanes through Airworthiness Directives (AD). The directive AD/AT/18 pertains to the replacement of parking brake valves in Airtractor AT-300, 400, and 500 series aircraft (sections 5/97). The directive applies to all AT-250, AT-300, AT-301, AT-302, AT-400, AT-400A, AT-401, AT-402, AT-501, and AT-502 series aircraft that are not already fitted with the Scott P/N 4500A-2 parking brake valve. The primary requirement is the replacement of the existing Gerdes P/N A-850-5 or Cleveland P/N 60-9 parking brake valve with the Scott P/N 4500A-2 valve, as per Snow Engineering Co. Service Letter #76 dated December 12, 1988. This change is necessitated by reports of the parking brake valve lever slipping from the OFF to the ON position during flight, which has resulted in several aircraft overturning upon landing.
The obligations under this directive are clear and time-bound. Aircraft owners or operators must ensure that the specified replacement is carried out at the next scheduled maintenance release issue after 31 May 1997, or by 31 December 1997, whichever comes first. The directive became effective on 24 April 1997, and compliance is mandatory to maintain the airworthiness of the affected aircraft. The directive references FAA AD 96-24-08 Amdt 39-9833, indicating a cross-jurisdictional recognition of the safety issue and the required action. Failure to comply with the directive could result in the aircraft not being deemed airworthy, which could have severe legal and safety consequences.
The consequences for non-compliance with the AD/AT/18 are significant. While specific penalties are not detailed in the legislative instrument, non-compliance with airworthiness directives generally leads to the aircraft being grounded until the necessary modifications are made. This can result in substantial operational disruptions and financial costs for the operator. Furthermore, if the non-compliance leads to an accident or incident, the operator could face additional civil and criminal liabilities, including potential prosecution under the Civil Aviation Act 1988. The safety of passengers and crew is paramount, and strict adherence to such directives is essential to prevent accidents and maintain the highest standards of aviation safety.