AD/BELL 212/54 - Main Transmission Lower Planetary Spider

Overview

The Civil Aviation Regulations 1998, enacted by the Parliament of Australia, serve to regulate the safe operation of aircraft within Australian airspace. The specific legislative instrument F2006B04586 addresses the safety of Bell Helicopter Textron 212 Series Helicopters, aiming to mitigate risks associated with the main transmission lower planetary spider. This directive was introduced to address the problem of in-service failures of the main transmission lower planetary spider, specifically for those helicopters equipped with part number 412-040-785-101. The policy objective is to ensure that such components are retired from service before they reach a critical point of failure, thereby enhancing overall aviation safety. Compliance with this directive requires the retirement of the specified spiders either before they accumulate 2500 hours of service or within 100 hours of the date 2 February 1995, whichever is later, following identified failures during manufacturer's fatigue tests.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, applies to all Bell Helicopter Textron 212 Series Helicopters equipped with the main transmission lower planetary spider part number 412-040-785-101. The regulations mandate the retirement of this specific component from service to ensure aviation safety. This directive applies to helicopters irrespective of their location within Australia and falls under the regulatory purview of the Commonwealth of Australia. The requirement necessitates that the specified spiders be retired from service either before reaching 2500 hours of time in service or within 100 hours of time in service after 2 February 1995, whichever is the later date. This mandate is grounded in the five failures of the component during the manufacturer's fatigue tests, establishing a fatigue life to mitigate in-service failures. The regulations do not exempt any helicopters from this requirement, and compliance is strictly enforced. The application of these directives can be further extended or specified through subordinate instruments issued by the Civil Aviation Safety Authority.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 105 under the Civil Aviation Safety Authority Schedule of Airworthiness Directives, contains a directive concerning the Bell Helicopter Textron 212 Series Helicopters, denoted as AD/BELL 212/54 (section 2). This directive mandates that the main transmission lower planetary spider with part number 412-040-785-101 must be retired from service. This requirement applies to all Bell Helicopter Textron 212 Series Helicopters that have this specific part installed. Operators and owners of these helicopters must ensure that the specified part is removed from service in accordance with the directive. The directive references FAA AD 94-18-09 Amdt 39-9022 and Bell Alert Service Bulletin ASB 212-93-83 Revision A for further guidance (section 2). It is crucial to note that this airworthiness directive does not limit the life of the alternative part, P/N 412-040-785-103. The directive imposes clear obligations on the operators and owners of Bell Helicopter Textron 212 Series Helicopters. They must retire the main transmission lower planetary spider P/N 412-040-785-101 from service before it reaches 2500 hours of time in service or within 100 hours of time in service after 2 February 1995, whichever is the later (section 3). This requirement is established to mitigate the risk of in-service failures, as evidenced by five failures during the manufacturer’s fatigue tests. The directive underscores the importance of adhering to these timelines to maintain the safety and airworthiness of the aircraft. Non-compliance with the airworthiness directive could have serious consequences. While the specific penalties or legal repercussions are not detailed within the directive, general Civil Aviation Regulations 1998 provide for potential enforcement actions. These can include fines, operational restrictions, or even the grounding of non-compliant aircraft. The penalties for non-compliance could be substantial, reflecting the importance of adhering to airworthiness directives to ensure the safety of aviation operations.