AD/HU 269/57 Amdt 4 - Centre Frame Aft Cluster Fitting

Overview

The Civil Aviation Safety Authority (CASA) introduced the Airworthiness Directive AD/HU 269/57 Amdt 4 on 10 June 2004, targeting specific models of Schweizer (Hughes) 269 Series Helicopters. This legislative instrument was enacted to address the critical safety issue identified by a fatal accident report, which indicated that the cause of the accident was fatigue failure of a centre frame aft cluster fitting. The directive is intended to ensure the safety of the aircraft by mandating the inspection and, if necessary, replacement of certain aft cluster fittings to prevent future failures. The objective of this Airworthiness Directive is to enhance the airworthiness of the affected helicopters by ensuring that any potentially unsafe fittings are either replaced or properly modified, thereby mitigating the risk of similar accidents in the future.

Scope and Application

This Airworthiness Directive (AD) applies to Schweizer (Hughes) 269 Series Helicopters, specifically models 269A, 269A-1, 269B, 269C, and 269C-1, that are equipped with a centre frame aft cluster fitting bearing part numbers 269A2234, 269A2234-3, 269A2235, or 269A2235-3. The directive mandates specific actions to address a previously identified unsafe condition associated with the centre frame aft cluster fitting. The AD is issued under subregulation 39.1 (1) of the Civil Aviation Safety Regulations 1998 by a delegate of the Civil Aviation Safety Authority, thereby carrying the full force of the regulations across the Commonwealth of Australia. The directive outlines mandatory actions, including the chemical removal of paint from the clevis lugs on each centre frame aft cluster fitting, followed by dye-penetrant inspection and subsequent replacement if cracks are found. If no cracks are detected, the fittings must be cleaned and repainted. Additionally, it specifies the replacement of certain unmodified aft cluster fittings with modified fittings or specific part numbers. Compliance with these requirements is crucial and must occur within specified intervals and timeframes, with particular attention to the timing of inspections and replacements depending on the part numbers in use. This AD does not explicitly mention exclusions or exemptions but ensures that all specified helicopters must adhere to the outlined safety measures.

Key Provisions

The Airworthiness Directive AD/HU 269/57 Amdt 4 pertains to Schweizer (Hughes) 269 Series Helicopters, specifically those with centre frame aft cluster fittings identified by part numbers 269A2234, 269A2234-3, 269A2235, or 269A2235-3 installed (Applicability). The requirement section of the AD outlines several actions to be taken to address potential safety issues. Firstly, the paint on the clevis lugs of each centre frame aft cluster fitting must be chemically removed, followed by washing and drying. These clevis lugs then need to be inspected using dye-penetrant technology (Requirement 1a-b). If any cracks are discovered during this inspection, the affected aft cluster fitting must be replaced with a serviceable part number 269A2234-3 or 269A2235-3 fitting before any further flight. Should no cracks be found, the fitting must be cleaned and repainted (Requirement 1c). Additionally, all aft cluster fittings with part numbers 269A2234 and 269A2235, not modified according to Kit part number SA-269K-106-1, must be replaced with fittings that have been modified in accordance with the same kit or replaced with part numbers 269A2234-3 and 269A2235-3 fittings (Requirement 2). The AD imposes specific obligations on the parties or entities it governs. Operators of the Schweizer (Hughes) 269 Series Helicopters must ensure that the actions outlined in the requirement section are carried out in accordance with the instructions provided and within the specified timeframes. For Requirement 1, the inspections and actions must be completed within 50 hours of time in service after 15 May 2003, and thereafter at intervals not exceeding 50 hours time in service, until the installation of the Aft Cluster Fitting Modification Kit, part number SA-269K-0106-1. For Requirement 2, the replacement of unmodified fittings must be completed within 150 hours of time in service or 6 months after 10 June 2004, whichever comes first. Failure to comply with the requirements of this Airworthiness Directive can result in serious consequences. The AD does not explicitly state the penalties or consequences for non-compliance, but non-compliance with ADs generally may lead to the grounding of the aircraft, which can have severe operational and financial repercussions for operators. Furthermore, persistent non-compliance could potentially lead to enforcement actions by the Civil Aviation Safety Authority (CASA), including fines, legal action, or other regulatory penalties as stipulated under the Civil Aviation Act 1988 and related regulations.