AD/DH 104/20 - Landing Gear Actuator Pistons - Inspections and Replacement

Overview

The Civil Aviation Regulations 1998, amended by the Legislative instrument F2006B08865, address the need for maintaining airworthiness standards in specific aircraft models, particularly focusing on the DH 104 (Dove) Series Aeroplanes. This regulation was enacted by the Parliament of the Commonwealth of Australia and is aimed at ensuring the safety and reliability of these aircraft by mandating regular inspections and necessary actions concerning the landing gear actuator pistons. The policy objective of this regulation is to mitigate risks associated with the Dunlop actuators P/N AH 8463 and AC 11130, particularly concerning pistons P/N AHO 19742, by requiring regular inspections for cracks and replacements to prevent potential failures that could compromise flight safety. The regulation ensures that any detected defects are addressed promptly and that maintenance intervals are strictly adhered to, thereby enhancing the overall safety profile of the affected aircraft models.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, addresses the airworthiness directives applicable to the DH 104 (Dove) series aeroplanes, encompassing all models equipped with Dunlop actuators P/N AH 8463 and AC 11130 and featuring pistons P/N AHO 19742. This regulation mandates that the landing gear actuator pistons must be inspected for signs of cracking at intervals not exceeding 200 landings and must be removed from service if a cracked piston crown is detected or at intervals not exceeding 10,000 landings, whichever occurs first. The application of these directives is national in scope, falling under the purview of the Commonwealth of Australia. Notably, compliance with Dove Modification No. 1144 negates the need for these specific inspection and replacement requirements. This legislative instrument provides clear operational guidelines to ensure the safety and airworthiness of the specified aircraft models.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 105, and the Civil Aviation Safety Authority Schedule of Airworthiness Directives AD/DH 104/20, pertain to the maintenance and safety requirements for the DH 104 (Dove) Series Aeroplanes. Section 1 of AD/DH 104/20 requires that for all models fitted with Dunlop actuators P/N AH 8463 and AC 11130, in which pistons P/N AHO 19742 are installed, certain actions must be taken. Firstly, the piston must be removed from the jack and inspected for any signs of cracking on the piston crown (Section 1(1)). Secondly, Dunlop pistons P/No. AHO 19742 must be removed from service (Section 1(2)). These inspections and removals must occur at specific intervals or upon detection of a cracked piston crown. The obligations imposed by this directive are stringent and clear. Operators and owners of the DH 104 (Dove) Series Aeroplanes must adhere to the inspection and removal requirements outlined. Specifically, for paragraph 1, the inspection must be carried out at intervals not exceeding 200 landings (Section 1(1)). For paragraph 2, the removal from service must occur whenever a cracked piston crown is detected or at intervals not exceeding 10,000 landings, whichever comes first (Section 1(2)). This directive is applicable to all relevant models, ensuring that safety standards are consistently maintained across the fleet. Failure to comply with these requirements can lead to significant consequences. While the Civil Aviation Regulations do not explicitly detail penalties for non-compliance with this specific directive, general aviation regulations provide that breaches can result in enforcement actions, including fines and potential grounding of the aircraft. The severity of the penalty can depend on the nature and extent of the non-compliance, with the potential for significant financial penalties and other enforcement measures being applied by the Civil Aviation Safety Authority. Additionally, non-compliance may result in the aircraft being deemed unairworthy, which could prevent it from operating until the issues are rectified.