AD/PA-24/33 Amdt 3 - Stabilator Torque Tube Bearing Block Attachment Fitting

Overview

The Civil Aviation Regulations 1998, enacted by the Australian Parliament, govern the safety standards for civil aviation in Australia. This legislation is integral to ensuring the safety of aircraft and passengers, addressing issues and gaps in aviation safety as they arise. PART 39 - 105 of these regulations includes specific directives for maintaining the airworthiness of certain aircraft, including the Piper PA-24 (Comanche) Series Aeroplanes, as detailed in AD/PA-24/33 Amendment 3. This amendment was introduced to address the problem of looseness in the stabilator torque tube bearing support fittings, which could lead to the loss of pitch control, posing a significant safety risk. The policy objective of this directive is to mandate regular inspections and corrective actions to ensure that these critical components remain secure, thereby maintaining the aircraft's airworthiness and enhancing flight safety.

Scope and Application

The Civil Aviation Regulations 1998, under Part 39, specifically Airworthiness Directives, applies to Piper PA-24 Comanche series aeroplanes with certain model and serial numbers, namely PA24-180, PA24-250, PA24-260, and PA24-400 within specified serial number ranges. This legislation is pertinent to the aviation industry, particularly those who operate or maintain these aircraft models. The geographic and jurisdictional reach of this directive is national, as it pertains to the civil aviation sector within Australia and must be adhered to by all relevant operators and maintenance personnel. The directive does not explicitly state any exclusions or exemptions; however, the compliance thresholds are clearly defined. The requirement to inspect and, if necessary, replace the stabilator torque tube bearing support fittings is mandatory for the specified aircraft models within the outlined timeframes. The directive is extended and clarified through amendments, such as the one effective from 15 September 1994, which adjusts the reinspection intervals and incorporates specific terminating actions to ensure ongoing airworthiness.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 105, mandate that the stabilator torque tube bearing support fittings of Piper PA-24 (Comanche) Series aeroplanes must be inspected and, if necessary, replaced to ensure airworthiness. This requirement is detailed in AD/PA-24/33 Amendment 3 (sections 1-6). The regulation applies to specific model and serial numbers, namely PA24-180, PA24-250, PA24-260, and PA24-400 within the serial number ranges provided. The inspection procedure involves removing the tailcone and rear aft fuselage access door, then manually checking the stabilator tip for looseness by applying fore and aft and up and down forces. If looseness is detected, the specified Piper Part No. 760 835 (Hi-Shear Rivet Replacement Kit) must be incorporated into the affected fitting, followed by reinstallation of the tailcone and rear aft fuselage access door. The obligations imposed by this directive on the relevant parties, primarily aircraft operators and maintenance personnel, include conducting the specified inspections within 100 hours of time in service after 15 September 1994, unless all four stabilator torque tube bearing support fittings have already been updated with Piper Kit Part No. 760 835. If the kit has not been applied to all four fittings, the inspections must be repeated at intervals not exceeding 100 hours until all fittings are secured. This directive supersedes previous requirements, which mandated inspections at intervals not exceeding 300 hours. The intent behind these stringent requirements is to prevent the loss of pitch control due to loose fittings, ensuring the safety of the aircraft and its occupants. Failure to comply with these airworthiness directives can result in significant legal and safety repercussions. The Civil Aviation Safety Authority (CASA) enforces these regulations rigorously, and non-compliance can lead to penalties, including fines and potential grounding of the aircraft. The maximum penalties for violations are not explicitly stated in the text provided, but they are severe enough to ensure adherence to the safety standards. Additionally, failure to comply with these directives can result in the aircraft being deemed unairworthy, which carries both civil and criminal consequences for the operators. It is crucial for all involved parties to meticulously follow the outlined procedures to avoid these serious outcomes.