Overview

The Civil Aviation Regulations 1998, specifically Part 39 – 107, includes an Airworthiness Directive (AD) that was enacted in 2001 to address a safety concern associated with the SIREN load release units on various Eurocopter helicopter models. This AD was issued by the Civil Aviation Safety Authority (CASA), under the authority of subregulation 39.1 (1) of the Civil Aviation Regulations 1998. The problem identified was a potential jamming of the ring on the cargo hook in the hook-open position, which could have occurred due to an anomaly in the load release unit locking catch, thereby posing a risk to the safe release of underslung loads. The policy objective behind this directive is to ensure the airworthiness of the affected aircraft by mandating specific corrective actions, as outlined in Eurocopter Alert Telex communications, to mitigate the identified safety risk.

Scope and Application

This Airworthiness Directive (AD) issued by the Civil Aviation Safety Authority (CASA) under the Civil Aviation Regulations 1998 pertains specifically to certain Eurocopter helicopter types equipped with SIREN load release units, as well as any other helicopter types similarly equipped. The AD applies to a comprehensive list of Eurocopter models including SA330 F, G, and J; AS332 C, C1, L, L1, and L2; AS350 B, BA, B1, B2, B3, BB, and D; AS355 E, F, F1, F2, and N; AS365 N, N1, N2, and N3; EC 120B; and EC 155 B. The purpose of this directive is to address an unsafe condition identified in the load release unit locking catch, which if unaddressed, could result in jamming of the ring on the cargo hook, thereby risking the release of an underslung load. The directive mandates compliance with specific Eurocopter Alert Telex instructions to rectify this issue. This directive became effective on 7 August 2001 and applies to all relevant aircraft before their next operation of specified load release units unless compliance records are already documented.

Key Provisions

The Airworthiness Directive (AD) issued by the Civil Aviation Safety Authority (CASA) mandates specific actions to be taken on certain Eurocopter helicopter types equipped with SIREN load release units, including models such as SA330 F, G, and J; AS332 C, C1, L, L1, and L2; AS350 B, BA, B1, B2, B3, BB, and D; AS355 E, F, F1, F2, and N; AS365 N, N1, N2, and N3; EC 120B; and EC 155 B (AD/SUPP/18, s. 10/2001). The directive requires compliance with specific Eurocopter Alert Telex instructions relevant to the load release units, as detailed in section 2 of the directive (AD/SUPP/18, s. 10/2001). The compliance period begins before the next operation of load release units AS21-5-(1 to 7) with a serial number below 415, and each time the load release unit is operated thereafter (AD/SUPP/18, s. 10/2001). The AD imposes obligations on helicopter operators to ensure that the load release units comply with the instructions given in the Eurocopter Alert Telex documents. Specifically, operators must check the clearance “J” in compliance with paragraph 2.A of the Requirement document before the next operation if the serial number of the load release unit is below 415 and the equipment log card does not already record compliance with the Requirement document (AD/SUPP/18, s. 10/2001). Furthermore, operators must follow the instructions in paragraph 2.B of the Requirement document each time the load release unit is operated (AD/SUPP/18, s. 10/2001). Failure to comply with the requirements of this AD may result in unsafe conditions that could lead to serious operational risks, including the jamming of the ring on the cargo hook in the hook-open position, which jeopardises the release of an underslung load (AD/SUPP/18, Background). The AD itself does not explicitly state the penalties for non-compliance, but non-compliance with CASA directives generally can result in civil penalties under the Civil Aviation Act 1988, including fines and potential grounding of the aircraft. Such penalties underscore the importance of adhering to ADs to maintain airworthiness and ensure safety in civil aviation operations.