AD/AC-SNOW/20 - Aileron Hinge Bracket Bolts

Overview

The Civil Aviation Regulations 1998, specifically under PART 39 - 105, address safety directives to ensure the safe operation of aircraft in Australian airspace. Enacted by the Civil Aviation Safety Authority, this legislation aims to mitigate risks and maintain the safety standards of aircraft by issuing directives that address specific maintenance and operational issues. The policy objective is to mandate corrective actions to prevent incidents that could compromise the safety of flights. This particular directive, AD/AC-SNOW/20, pertains to the Ayres Thrush (Snow) Commander Series Aeroplanes, focusing on the replacement of aileron hinge bracket bolts to prevent in-flight control failures. The Civil Aviation Regulations 1998, through the authority of the Civil Aviation Safety Authority, mandate that all S2R-T65, -T34, -T15, -T11, and -R1820 aircraft affected by Ayres Corporation Service Bulletin SB-AG-22 must replace the lower attachment bolts on all six aileron brackets with larger diameter bolts to prevent potential control failures. This directive was introduced in response to a reported incident where the controls of an aircraft jammed due to the failure of these bolts, highlighting the necessity for immediate and corrective action to ensure the safety and reliability of these aircraft in Australian airspace. Compliance with this directive is required within specified timeframes post the directive's issuance on 21 June 1993.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, pertains to the safety directives issued by the Civil Aviation Safety Authority (CASA) for ensuring the airworthiness of aircraft. This particular legislative instrument applies to all S2R-T65, -T34, -T15, -T11, and -R1820 aircraft referenced by Ayres Corporation Service Bulletin SB-AG-22, focusing on the replacement of the lower attachment bolts from all six aileron brackets. The requirement is to either replace these bolts with larger diameter ones within 5 flight hours following 21 June 1993, or alternatively, to replace the existing bolts with new ones of the same size within 5 flight hours after the same date, followed by replacing these new bolts with larger diameter ones within 120 flight hours from the installation of the new bolts. The regulation is effective from 21 June 1993, following a report of an incident where flight controls became jammed due to bolt failure. This directive is a national standard enforced across Australia under the Commonwealth of Australia's authority, and no specific exclusions or exemptions are outlined within this legislative text.

Key Provisions

The Civil Aviation Regulations 1998, specifically PART 39 - 105, mandate the implementation of Airworthiness Directives (AD) to ensure the safety of aircraft operations. In this context, AD/AC-SNOW/20 pertains to Ayres Thrush (Snow) Commander Series Aeroplanes and specifically addresses the issue of aileron hinge bracket bolts. This directive is applicable to all S2R-T65, -T34, -T15, -T11, and -R1820 aircraft as referenced by Ayres Corporation Service Bulletin SB-AG-22. The directive requires the replacement of the lower attachment bolts from all six aileron brackets with larger diameter bolts as detailed in the aforementioned service bulletin. The replacement must occur within 5 flight hours after 21 June 1993 or, alternatively, within the specified timeframe involving a two-step replacement process (Section 9/93 DM). Operators and owners of the specified aircraft must comply with the Airworthiness Directive by ensuring that the prescribed modifications are made to the aileron hinge bracket bolts. The compliance timeline requires immediate action within 5 flight hours after the directive's effective date or, if opting for the two-step process, within 120 flight hours from the installation of the new bolts. Failure to adhere to these requirements could result in the aircraft being deemed unairworthy, potentially leading to grounding and further enforcement actions by the Civil Aviation Safety Authority (CASA). Compliance with the directive is critical to maintaining the airworthiness and safety standards of the aircraft. In the event of non-compliance with the Airworthiness Directive AD/AC-SNOW/20, operators and owners could face significant legal repercussions. Breaches of these regulations could result in penalties, including fines and potential criminal charges. Specifically, non-compliance may lead to enforcement actions by CASA, which could include the issuance of a Notice of Violation, and in severe cases, criminal charges under the Civil Aviation Act 1988. The maximum penalties for breaches could include substantial fines and imprisonment, depending on the severity and impact of the non-compliance on aviation safety. Therefore, it is imperative for all relevant parties to adhere strictly to the provisions of this directive to avoid these severe consequences.