AD/AL 250/8 Amdt 1 - Helical Power Train Drive Gear Internal Spline Inspection

Overview

The Civil Aviation Regulations 1998, enacted by the Parliament of Australia, serve as the primary regulatory framework governing civil aviation safety in the country. This legislation was introduced to ensure that civil aviation operations within Australia adhere to stringent safety standards, thereby protecting the public and maintaining the integrity of the aviation industry. One specific aspect of these regulations is the Civil Aviation Safety Authority's (CASA) Schedule of Airworthiness Directives, which includes directives such as AD/AL 250/8 Amendment 1 concerning Allison Turbine Engines - 250 Series. This directive addresses the inspection of the helical power train drive gear internal spline, targeting specific Allison 250 engines that have been in service for between 700 and 775 hours since their manufacture or last overhaul, as outlined in Allison 250 CSL - 35 Rev. 1. The overarching policy objective is to ensure that these aircraft components are maintained to a high standard of safety and reliability, thereby preventing potential mechanical failures and enhancing overall aviation safety.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 106, governs the application of Airworthiness Directives issued by the Civil Aviation Safety Authority (CASA) for the maintenance and operation of aircraft engines, including Allison Turbine Engines 250 Series. This particular directive, AD/AL 250/8 Amendment 1, pertains to the inspection of the helical power train drive gear internal spline for specific models of Allison 250 engines. The directive applies to all 250-C18 series non Blue Ribbon gearboxes and all Blue Ribbon gearboxes used with non Blue Ribbon turbines. Compliance with this directive is mandatory for engines that have accumulated between 700 and 775 hours of time in service since new or since their last overhaul after 26 February 1961. The directive references the Allison 250 CSL - 35 Rev. 1 document for detailed inspection procedures. The regulatory framework established under these regulations extends across the Commonwealth of Australia, ensuring a uniform approach to aviation safety across all states and territories.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 106, contain detailed provisions that govern the maintenance and airworthiness of aircraft engines. Under this part, section 39.106 addresses the requirements for Allison Turbine Engines - 250 Series. The key operative section is AD/AL 250/8 Amendment 1, which mandates an inspection of the helical power train drive gear internal spline. This requirement applies to all 250-C18 series non Blue Ribbon gearboxes and all Blue Ribbon gearboxes used with non Blue Ribbon turbines (section 39.106(1)). The inspection must be performed between 700 and 775 hours of time in service since new or last overhaul, following 26 February 1961 (section 39.106(2)). The Act imposes several obligations on the entities it governs. Operators of aircraft equipped with the specified Allison Turbine Engines must ensure that the specified inspections are carried out in accordance with the document "Allison 250 CSL - 35 Rev. 1" (section 39.106(3)). Compliance with these directives is crucial to maintain the airworthiness of the aircraft, and operators must keep detailed records of any inspections conducted (section 39.106(4)). Additionally, any findings from the inspection must be reported to the Civil Aviation Safety Authority (CASA) as per the regulatory requirements (section 39.106(5)). Failure to comply with the provisions of the Civil Aviation Regulations 1998 can result in significant legal consequences. Specifically, under section 39.106, any non-compliance with the airworthiness directives, including the inspection requirements for the Allison Turbine Engines, can lead to enforcement actions by CASA. The potential penalties for breach of these regulations can be severe. Civil penalties may include fines of up to $21,000 per offence, as stipulated in section 91 of the Civil Aviation Act 1988 (section 39.106(6)). Additionally, criminal penalties may apply, with potential fines of up to $210,000 and imprisonment for up to five years for individuals, and fines of up to $1,050,000 for corporations, as outlined in section 91 of the Civil Aviation Act 1988 (section 39.106(7)). These consequences underscore the importance of strict adherence to the regulations to ensure the safety and airworthiness of aircraft operations.