AD/DAUPHIN/43 - Main Rotor Head Frequency Adapter

Overview

The Civil Aviation Regulations 1998, specifically within Part 39 - 105, establish safety directives to ensure the airworthiness of aircraft in Australia. One such directive, AD/DAUPHIN/43, pertains to the Eurocopter SA 360 and SA 365 (Dauphin) Series Helicopters. This directive was introduced to address issues with the main rotor head frequency adapters, which had been found to cause severe vibrations due to separation of the elastomer and the centre metal section. The directive mandates that corrective actions be taken in accordance with Eurocopter AS 365 SB 01.00.44, ensuring compliance within a specific timeframe to maintain operational safety. The directive was enacted by the Civil Aviation Safety Authority, aiming to mitigate risks associated with the identified production fault in certain frequency adapters. The directive applies to specific models of the Dauphin series, namely AS365N, N1, and N2, which were fitted with particular frequency adapters manufactured before the second quarter of 1991. Compliance is required within 100 hours of service time after 12 September 1996 or before 12 March 1997, whichever comes first. This requirement ensures that any affected helicopters are inspected and repaired promptly to prevent potential hazards, thereby safeguarding both the aircraft and its occupants.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, pertains to the safety directives for aircraft operated within Australia, with this particular Airworthiness Directive (AD) focusing on Eurocopter SA 360 and SA 365 (Dauphin) Series helicopters. This directive applies to AS365N, N1, and N2 models equipped with specific main rotor head frequency adapters, namely P/N 704A33-640-031 (E1T2624-01A) or P/N 704A33-640-046 (E1T3023-01), which were manufactured before the second quarter of 1991 and meet certain serial number criteria. The requirement for compliance is to undertake the corrective action as outlined in Eurocopter AS 365 SB 01.00.44, which addresses the issue of severe vibration due to separation of the elastomer and the centre metal section of the frequency adapters. Compliance with this directive is mandatory and must be achieved within 100 hours of time in service after 12 September 1996 or before 12 March 1997, whichever occurs first. The directive is applicable across the Commonwealth of Australia, underscoring the importance of stringent safety measures for aircraft operations within the country.

Key Provisions

The Civil Aviation Regulations 1998, particularly Part 39 - 105, contains specific directives for maintaining the airworthiness of certain Eurocopter SA 360 and SA 365 (Dauphin) Series helicopters. The key provision, as outlined in AD/DAUPHIN/43, mandates action on the main rotor head frequency adapters for specific models. The directive applies to AS365N, N1, and N2 helicopters that are equipped with certain frequency adapters (sections 1 and 2). These helicopters must adhere to the action specified in Eurocopter AS 365 SB 01.00.44 and must comply with the directive within a strict timeline: either 100 hours of time in service after 12 September 1996 or by 12 March 1997, whichever comes first (section 10). Operators of these helicopters must ensure that the main rotor head frequency adapters are inspected and, if necessary, repaired or replaced to prevent severe vibration caused by separation of the elastomer and the centre metal section. This separation could be due to production faults in certain frequency adapters (section 2). The requirement is to follow detailed instructions provided in Eurocopter AS 365 SB 01.00.44, ensuring that the corrective measures are implemented correctly (section 1). Additionally, the directive references DGAC AD 96-117-040, which provides further guidance and context for the required actions (section 1 Note). Failure to comply with these airworthiness directives can result in severe operational risks, including the potential for in-flight failures. The Civil Aviation Safety Authority (CASA) mandates these directives to ensure the safety of the aircraft and its occupants. Non-compliance with these regulations can lead to serious consequences, including penalties for the operators and potential grounding of the aircraft until the required actions are taken. The precise nature and extent of penalties are governed by the overarching Civil Aviation Act 1988 and associated regulations, but they can include substantial fines and operational restrictions.