Overview

The Civil Aviation Safety Regulations 1998, enacted by the Australian Parliament, serve as a comprehensive framework for ensuring the safety and airworthiness of civil aviation within Australia. One specific legislative instrument under this Act is the Airworthiness Directive issued by the Civil Aviation Safety Authority (CASA) to address safety issues pertaining to specific aircraft models. For example, AD/HS 125/169 issued on 6 May 2003 targets British Aerospace BAe 125 Series aeroplanes, including models DH.125, BH.125, HS.125, and BAe.125, and the Hawker 800XP aircraft with certain serial numbers. The directive mandates the inspection and replacement of specific tie-bolt nuts to prevent potential separation of the main landing gear wheels, which could result in severe damage or injuries. This directive was introduced in response to a requirement by the Federal Aviation Administration (FAA) to mitigate risks associated with loose or missing tie-bolts, ensuring compliance with safety standards within a specified timeframe.

Scope and Application

The Airworthiness Directive (AD) issued under the Civil Aviation Safety Regulations 1998 applies specifically to the British Aerospace BAe 125 Series Aeroplanes, including models DH.125, BH.125, HS.125, and BAe.125 as listed in Raytheon Mandatory Service Bulletin (MSB) 32-3522, dated September 2002, and the Model Hawker 800XP aircraft with serial numbers up to and including 258581, equipped with certain Dunlop wheels. The AD mandates the inspection of the main landing gear wheels to determine the part numbers of the tie-bolt nuts and requires the replacement of any part number NAS1804 tie-bolt nut with an authorised new part number before further flight. The directive became effective on 7 May 2003 and requires compliance within 10 landings or 12 days after this date, whichever occurs first. The AD extends to the entire Commonwealth of Australia and is applicable to aircraft registered and operated within this jurisdiction.

Key Provisions

The Airworthiness Directive (AD) AD/HS 125/169 issued by the Civil Aviation Safety Authority (CASA) under subregulation 39.1(1) of the Civil Aviation Safety Regulations 1998 (CASR 1998) mandates specific actions to address a safety concern related to the tie-bolt nuts of certain British Aerospace BAe 125 Series aeroplanes. The directive applies to the DH.125 Series, BH.125 Series, HS.125 Series, and BAe.125 Series aircraft, as well as the Hawker 800XP aircraft with certain serial numbers and Dunlop wheels. The primary requirement of the AD is to inspect the main landing gear wheels to determine the part numbers of the tie-bolt nuts, in accordance with Raytheon Mandatory Service Bulletin (MSB) 32-3522. If any part number NAS1804 tie-bolt nut is found installed, it must be replaced with a new part number FN22A524 tie-bolt nut or an authorised alternative (Dunlop tie-bolt nut part numbers H5227C-5CW, SN407C-054, or LH13318-5) before further flight. This replacement must also comply with the instructions set out in MSB 32-3522. The compliance period for this directive is within 10 landings or 12 days after 7 May 2003, whichever occurs first. The AD imposes several obligations on the parties or entities it governs. Firstly, it requires operators and owners of the specified aircraft models to conduct the mandated inspection of the tie-bolt nuts on the main landing gear wheels. This inspection must be performed in accordance with the detailed instructions provided in Raytheon MSB 32-3522. Secondly, if the NAS1804 tie-bolt nut is identified during the inspection, operators and owners must replace it with a new part number FN22A524 tie-bolt nut or an authorised alternative before the aircraft is flown again. This replacement must also be carried out following the guidelines outlined in MSB 32-3522. Finally, operators and owners must ensure that these actions are completed within the specified compliance period to maintain the airworthiness of the aircraft. Failure to comply with the AD may result in significant consequences. The AD does not explicitly state the penalties for non-compliance, but it is reasonable to infer that failure to adhere to airworthiness directives can lead to civil or criminal penalties under the Civil Aviation Act 1988 and the CASR 1998. Such penalties may include fines, suspension of airworthiness certificates, or other regulatory actions deemed necessary by CASA. The specific penalties would depend on the nature and severity of the non-compliance, as well as any resultant safety risks or incidents. Operators and owners are, therefore, strongly advised to ensure strict adherence to the AD to avoid any potential legal or safety repercussions.