AD/HU 269/68 Amdt 1 - Lower Pulley Bearings and Housings - Inspection

Overview

The Civil Aviation Regulations 1998, enacted by the Parliament of the Commonwealth of Australia, aims to ensure the safety and efficiency of civil aviation operations. This legislation, administered by the Civil Aviation Safety Authority, addresses safety concerns and compliance issues in the aviation sector to mitigate risks associated with air travel. The amendment in question, specifically Part 39 - 105 AD/HU 269/68, was introduced to address a critical safety concern regarding the lower pulley bearings and housings in Schweizer (Hughes) 269 Series Helicopters, identified by the manufacturer as having the potential to adversely affect the life of the bearings. The policy objective is to enhance the safety of air travel by mandating regular inspections and replacements of these components to prevent potential failures and ensure the continued airworthiness of the affected helicopters.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, mandates compliance with Airworthiness Directives (AD) issued by the Civil Aviation Safety Authority (CASA) for certain aircraft. This regulation applies to all Schweizer (Hughes) 269 Series helicopters, including models 269A, 269A-1, 269B, 269C, and TH-55A. The directive, AD/HU 269/68 Amendment 1, concerns the inspection and potential replacement of lower pulley bearings and housings to ensure safety and operational integrity. The directive requires the inspection of specific lower pulley bearings (P/N 269A5050-57 or 269A5050-80) in accordance with detailed service instructions, and mandates the retirement of these bearings after a certain number of service hours. It also includes specific requirements for helicopters equipped with different types of bearing straps and frames. Compliance with these directives is mandatory, with inspections and replacements to be conducted within specific timeframes following the directive’s issuance date of 17 September 1993. Failure to adhere to these regulations may result in the grounding of the affected aircraft until the required actions are completed.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39 - 105, outlines the Civil Aviation Safety Authority's (CASA) schedule of airworthiness directives for Schweizer (Hughes) 269 Series Helicopters. This includes a directive, AD/HU 269/68 Amendment 1, which mandates specific actions concerning lower pulley bearings and housings. The directive applies to all model 269A, 269A-1, 269B, 269C, and TH-55A helicopters. The directive requires an inspection of all lower pulley bearings with part numbers 269A5050-57 or 269A5050-80, which must be performed in accordance with Part 1 of Hughes Service Instruction Notice (SIN) N-146.2 or Part III of Hughes SIN N-164 (sections 1 and 2). The directive also mandates the retirement from service of all P/N 269A5050-57 or -80 bearings (section 2). For helicopters equipped with sheet metal bearing straps P/N 269A5463, specific actions must be taken as outlined in Part 1 of Hughes SIN N-146.2 (section 3). Helicopters equipped with machined lower pulley bearing caps that are part of a 269A5573-11 “H” frame assembly must be inspected in accordance with Part 1 of Hughes SIN N-164 (section 4). Compliance with this directive involves several key requirements. The lower pulley bearings must be inspected within 100 hours of time in service from 17 September 1993, unless they have already been inspected in accordance with the requirement document (section 1). Reinspection of all bearings must occur at intervals not exceeding 300 hours of time in service. Bearings that have exceeded 1,700 hours of time in service must be replaced within 100 hours of time in service from 17 September 1993. Those that have not exceeded 1,700 hours of time in service by 17 September 1993 must be replaced at 1,800 hours of time in service, with subsequent replacements occurring at intervals not exceeding 1,800 hours of time in service (section 2). Inspections of sheet metal bearing straps and machined lower pulley bearing caps must be performed within 50 hours of time in service from 17 September 1993, unless previously carried out (sections 3 and 4). Failure to comply with the provisions outlined in AD/HU 269/68 Amendment 1 may result in serious safety risks and legal consequences. While the Civil Aviation Regulations 1998 do not explicitly state penalties for non-compliance with airworthiness directives, non-compliance can lead to significant civil and criminal penalties under the Civil Aviation Act 1988 and other related legislation. These can include fines and imprisonment, depending on the severity of the breach and its impact on aviation safety. Additionally, operators may face operational restrictions or grounding of the affected aircraft until compliance is achieved, leading to potential financial losses and reputational damage.