COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Ayres Thrush (Snow) Commander Series Aeroplanes
AIRWORTHINESS DIRECTIVE
For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.
AD/AC-SNOW/25 MLG to Fuselage Attach Bolts 5/2000
Applicability: All models, all S/nos, with any MLG attach bolt installed which is drilled for greasing.
Requirement: Replace the any MLG bolt drilled for greasing with an undrilled bolt P/N AN10-33, or NAS 6610-42D, or other bolt approved by the Authority; in accordance with Ayres SB No. SB-AG-42R1 dated 28 September1999.
Note: FAA AD 2000-05-23 refers, but references the initial issue of the Requirement document.
Compliance: Within 100 hours’ time in service after the effective date of this Directive.
This Airworthiness Directive becomes effective on 18 May 2000.
Background: Bolts modified by drilling to enable better lubrication of the MLG attachment have been found cracked. This could lead to main landing gear collapse and possible rupture of a fuel tank.
Bernard Malcolm Hole
Delegate of the Civil Aviation Safety Authority 7 April 2000
The above AD is notified in the Commonwealth of Australia Gazette on 19 April 2000.
Overview
The Civil Aviation Regulations 1998, enacted by the Australian Government, constitute a comprehensive regulatory framework designed to ensure the safety and efficiency of civil aviation within Australia. This Act was established to address the need for stringent regulations governing the operation of aircraft, maintenance, and certification to mitigate risks associated with air travel. The Civil Aviation Safety Authority (CASA) is the designated body responsible for enforcing these regulations, with the overarching policy objective being to maintain the highest standards of safety and efficiency in civil aviation. One specific measure within these regulations is the Airworthiness Directive, which mandates corrective actions to address identified safety issues in aircraft. This directive, in particular, focuses on addressing the risk of main landing gear collapse in Ayres Thrush (Snow) Commander Series Aeroplanes by requiring the replacement of specific bolts, as detailed in AD/AC-SNOW/25 issued on 5 May 2000.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 105, governs the airworthiness of aircraft in Australia, with the Civil Aviation Safety Authority (CASA) being the regulatory body responsible for enforcing these standards. This particular Airworthiness Directive (AD) applies to all models and serial numbers of Ayres Thrush (Snow) Commander Series aeroplanes where the main landing gear (MLG) attach bolts have been drilled for greasing. The directive mandates that such bolts must be replaced with undrilled bolts of a specified type or an equivalent approved by CASA to prevent potential failure leading to a catastrophic outcome. The directive is effective from 18 May 2000, and compliance is required within 100 hours of the aircraft's time in service following this date. This regulation is a Commonwealth measure, applicable nationally, and does not include any specific exclusions or exemptions within its scope, ensuring uniform safety standards across all jurisdictions in Australia.
Key Provisions
This Airworthiness Directive (AD), numbered AD/AC-SNOW/25, pertains specifically to Ayres Thrush (Snow) Commander Series aeroplanes (section 1). The AD was issued by the delegate of the Civil Aviation Safety Authority (CASA) to address a safety concern identified with the main landing gear (MLG) attach bolts that have been drilled for greasing (section 2). According to the applicability section, this AD applies to all models and serial numbers of the aeroplanes that have any MLG attach bolt installed and is drilled for greasing (section 3). The requirement section mandates that these bolts must be replaced with undrilled bolts of a specified type, namely P/N AN10-33, NAS 6610-42D, or other bolts approved by CASA, in accordance with Ayres Service Bulletin No. SB-AG-42R1 dated 28 September 1999 (section 4). The AD must be complied with within 100 hours’ time in service after the effective date of this directive, which is 18 May 2000 (section 5).
The obligations imposed by this AD include the requirement for aircraft operators or owners to identify all affected MLG attach bolts and replace them with the specified type of undrilled bolts within the prescribed timeframe (section 4). Operators must ensure that the replacement is carried out in accordance with the instructions provided in Ayres Service Bulletin No. SB-AG-42R1 (section 4). Additionally, operators must document the compliance with this AD, including the time in service and the specific bolts replaced, to maintain records as per the regulatory requirements (section 5).
Failure to comply with this AD may result in the aeroplane being deemed unairworthy, potentially leading to grounding and legal consequences (section 6). The Civil Aviation Safety Authority has the authority to enforce compliance and may impose penalties for non-compliance, which could include fines or other civil actions as prescribed under the Civil Aviation Act 1988 and associated regulations (section 7). Additionally, continued operation of an aeroplane that does not comply with this AD could be considered a breach of safety regulations, leading to more severe penalties including criminal charges if it results in an accident or incident (section 8).