AD/G164/5 Amdt 1 - Elevator Torque Tubes - Inspection

Overview

The Civil Aviation Safety Authority (CASA) introduced this amendment to the Civil Aviation Regulations 1998 to address safety concerns related to the elevator torque tubes in Schweizer (Grumman) G-164 (Ag-Cat) series aeroplanes. This legislative instrument, known as AD/G164/5 Amendment 1, targets specific models of the Ag-Cat aircraft and aims to mitigate the risk of structural failure by requiring regular inspections of the elevator torque tubes for cracking. The objective of this directive is to ensure the ongoing airworthiness of these aircraft by mandating compliance with specified maintenance procedures, thereby enhancing flight safety and reducing the likelihood of accidents due to mechanical failure. CASA, as the enacting body, has established these regulations to uphold stringent safety standards within Australia's civil aviation sector.

Scope and Application

The Civil Aviation Safety Authority (CASA) administers the Civil Aviation Regulations 1998 under which the Airworthiness Directives are issued. This legislation applies specifically to all models G164 and G164A of Schweizer (Grumman) G-164 (Ag-Cat) series aeroplanes that have elevator serial numbers ranging from 1 to 461. The directive mandates the inspection of the left and right hand elevator torque tubes for any signs of cracking, particularly in areas adjacent to the inboard rib attachment welds and where the two 1/8" diameter blind rivets connect the right hand elevator leading edge skin cover to the torque tube. Any identified cracks must be repaired following the guidelines outlined in Grumman Ag-Cat Service Bulletin No. 33. The requirement for these inspections must be adhered to at intervals not exceeding 100 hours of time in service, ensuring the ongoing airworthiness and safety of the aircraft. This legislation is applicable nationally across the Commonwealth of Australia and is enforced by CASA to maintain safety standards within the civil aviation industry.

Key Provisions

The main operative sections of the AD/G164/5 Amendment 1 (sections 5/66) pertain to the inspection and repair of elevator torque tubes on Schweizer (Grumman) G-164 (Ag-Cat) Series Aeroplanes. Specifically, the regulation mandates that all models G164 and G164A with elevator serial numbers from 1 to 461 must undergo an inspection of the left and right hand elevator torque tubes. These inspections should focus on identifying any cracks near the inboard rib attachment welds and at the points where the two 1/8" diameter blind rivets attach the right hand elevator leading edge skin cover to the torque tube. If any cracks are found, they must be repaired following the instructions provided in Grumman Ag-Cat Service Bulletin No. 33. The obligations imposed by this regulation are straightforward yet critical. Aircraft operators and maintenance personnel must ensure that the specified inspections are conducted at intervals not exceeding 100 hours of time in service. This requirement underscores the importance of regular maintenance and vigilance in ensuring the structural integrity of the aircraft. Operators must maintain accurate records of inspections and repairs to demonstrate compliance with these regulations, ensuring that the aircraft remains airworthy and safe for operation. Failure to comply with the AD/G164/5 Amendment 1 could result in serious civil or criminal consequences. The Civil Aviation Safety Authority (CASA) takes violations of airworthiness directives very seriously, and non-compliance can lead to enforcement actions. These may include fines, penalties, or the grounding of the aircraft until the required repairs are completed. The specific penalties are not detailed in the regulation but typically align with the severity of the non-compliance and the risk posed to aviation safety.