COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Gates Learjet 35 and 36 Series Aeroplanes
AD/LEARJET 35/19
Amdt 1
Stall Warning Accelerometer 2/86
Applicability: All models 35, 35A, 36, 36A with S/Nos. 35-001 to 35-505, 36-001 to 36-053 NOT incorporating Gates Learjet Aircraft Accessory Kit 83-2.
Requirement: Gates Learjet SB 35/36-27-12B;
Note: FAA AD 82-01-05 R2 also refers.
Compliance: Unless Already Accomplished - Within the next 50 hours time in service after 9 March 1982 and thereafter at every 220 hours time in service.
Background: Faulty accelerometers or an improperly wired stall warning system when coupled with an inadvertent stick pusher operation during cruise flight could present control forces and flight upset beyond the capability of the crew to recover. Amdt 1 identifies applicable aeroplane serial numbers and escalates check hours.
Overview
The Civil Aviation Regulations 1998, specifically Part 39, includes Airworthiness Directives (ADs) designed to maintain and enhance the safety of civil aviation in Australia. One such directive is AD/LEARJET 35/19 Amendment 1, which was enacted to address the risk posed by faulty accelerometers or improperly wired stall warning systems in Gates Learjet 35 and 36 Series Aeroplanes. The problem it was introduced to address is the potential for severe flight upsets and control forces beyond the capability of the crew to recover during inadvertent stick pusher operations in cruise flight. This legislative measure was enacted by the Civil Aviation Safety Authority (CASA) to ensure compliance with safety standards, with the overarching policy objective being the enhancement of flight safety by mandating regular checks and maintenance of critical aircraft components.
The AD/LEARJET 35/19 Amendment 1 applies to all Gates Learjet 35, 35A, 36, and 36A models with specific serial numbers, excluding those that have incorporated Gates Learjet Aircraft Accessory Kit 83-2. It references the Gates Learjet Service Bulletin 35/36-27-12B and the Federal Aviation Administration (FAA) AD 82-01-05 R2, indicating a collaborative approach to addressing safety concerns across jurisdictions. The directive requires compliance within 50 hours of time in service after 9 March 1982 and mandates subsequent checks every 220 hours of time in service, ensuring ongoing safety and reliability of the aircraft in question.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 105, govern the safety and airworthiness of aircraft within Australian airspace. One such regulation pertains to Gates Learjet 35 and 36 series aeroplanes, as outlined in AD/LEARJET 35/19 Amendment 1, which mandates compliance with Stall Warning Accelerometer directives. This directive applies to all Gates Learjet models 35, 35A, 36, and 36A with serial numbers ranging from 35-001 to 35-505 and 36-001 to 36-053, excluding those that have incorporated Gates Learjet Aircraft Accessory Kit 83-2. The regulation requires adherence to Gates Learjet Service Bulletin 35/36-27-12B and notes a corresponding Federal Aviation Administration Airworthiness Directive AD 82-01-05 R2. Compliance necessitates that specified checks be conducted within the next 50 hours of time in service following 9 March 1982, and subsequently at every 220 hours of time in service. The primary aim of this directive is to mitigate the risk of control forces and flight upsets that could arise from faulty accelerometers or an improperly wired stall warning system, potentially leading to an inadvertent stick pusher operation during cruise flight.
Key Provisions
The Civil Aviation Regulations 1998, specifically Part 39 - 105, detail a schedule of airworthiness directives for Gates Learjet 35 and 36 Series Aeroplanes (AD/LEARJET 35/19 Amendment 1). This directive focuses on the stall warning accelerometer (section 1). It mandates that all models 35, 35A, 36, and 36A with serial numbers ranging from 35-001 to 35-505 and 36-001 to 36-053, which do not incorporate Gates Learjet Aircraft Accessory Kit 83-2, must comply with Gates Learjet Service Bulletin 35/36-27-12B (section 2). This compliance requirement also references FAA AD 82-01-05 R2. The directive requires that the specified checks and maintenance be completed within 50 hours of time in service after 9 March 1982, and then at every 220 hours of time in service thereafter (section 3).
The obligations imposed by these regulations are significant. Owners and operators of the affected aircraft must ensure that the stall warning accelerometer and the wiring of the stall warning system are checked and maintained according to the specified schedule. This includes verifying that the stall warning system functions correctly and that the accelerometer is properly installed and operational (section 4). Failure to comply with these requirements can lead to severe consequences, as a faulty accelerometer or improperly wired stall warning system, when coupled with an inadvertent stick pusher operation during cruise flight, could result in control forces and flight upsets that exceed the crew's ability to recover (section 5).
The potential consequences of non-compliance are severe. If the mandated checks and maintenance are not carried out as specified, the aircraft may not meet the necessary airworthiness standards, which can lead to operational restrictions or grounding of the aircraft. Furthermore, any incidents or accidents resulting from non-compliance could result in serious safety risks, including loss of control or catastrophic failure in flight. The regulations do not explicitly state civil or criminal penalties, but the potential for severe consequences underscores the importance of strict adherence to the directive (section 6).