AD/TFE731/35 - High Pressure Turbine Rotor Discs Curvic Couplings

Overview

The Civil Aviation Act 1988, enacted to ensure the safety of air navigation, empowers the Governor-General to make regulations under section 98 for this purpose. The Act also delegates to the Civil Aviation Safety Authority (CASA) the ability to issue airworthiness directives (ADs) through regulation 39.001 of the Civil Aviation Safety Regulations 1998, which were established to maintain and ensure airworthiness. An AD is a legislative instrument, disallowable under section 46A of the Acts Interpretation Act 1901, and subject to the Legislative Instruments Act 2003. This legislation responds to Australia’s obligations under Annex 8 of the Convention on International Civil Aviation, which assigns the State of Design the responsibility for continuing airworthiness of aircraft types and mandates that the State of Registry adopt requirements to ensure airworthiness. CASA issues Australian ADs in alignment with directives from the State of Design, such as the US Federal Aviation Administration’s AD 2008-02-19 concerning Honeywell TFE 731 series engines, which CASA has assessed and issued as Australian AD/TFE 731/35, effective from 8 May 2008. Due to the international nature of these directives and the statutory obligations involved, no public consultation has been conducted, and the Office of Best Practice Regulation has determined that a Regulatory Impact Statement is not required.

Scope and Application

The Civil Aviation Act 1988, along with the Civil Aviation Safety Regulations 1998, applies to all matters related to the safety of air navigation within Australia and its territories. Specifically, the Act empowers the Governor-General to create regulations for air navigation safety, and under regulation 39.001, the Civil Aviation Safety Authority (CASA) can issue airworthiness directives (ADs) for specific types of aircraft or aeronautical products. These ADs serve as legislative instruments, subject to disallowance and regulation under the Acts Interpretation Act 1901 and the Legislative Instruments Act 2003. The ADs are intended to ensure the continuing airworthiness of aircraft and are a common form of compliance with international civil aviation standards, particularly those outlined in Annex 8 of the Convention on International Civil Aviation. The State of Registry, in this case CASA, is responsible for ensuring the compliance of aircraft within its jurisdiction with these ADs. The issuance of an AD, such as AD/TFE 731/35, is a direct response to an AD issued by the State of Design, which in this case is the US FAA for the Honeywell TFE 731 series engines, and does not require public consultation or a Regulatory Impact Statement.

Key Provisions

The main operative sections of the Civil Aviation Act 1988 and the Civil Aviation Safety Regulations 1998 empower the Civil Aviation Safety Authority (CASA) to issue airworthiness directives (ADs) as detailed in regulation 39.001 (subsection 5) of the Civil Aviation Safety Regulations 1998. An AD is a legislative instrument under section 6 of the Legislative Instruments Act 2003. These directives are issued in response to identified safety concerns with aircraft types or aeronautical products, and they are instrumental in maintaining the continuing airworthiness of aircraft. The State of Design, which is the State where the aircraft type was designed, holds the primary responsibility for ensuring the continuing airworthiness of the aircraft type, as per Annex 8 to the Convention on International Civil Aviation. Consequently, the State of Registry, which is the country where the aircraft is registered, must ensure the implementation of the airworthiness requirements set forth by the State of Design. The obligations imposed by these provisions require CASA, as the national airworthiness authority, to assess any airworthiness directives issued by the State of Design. If deemed necessary, CASA must then issue an Australian AD to mandate the airworthiness requirements for aircraft on the Australian Register. For instance, following the issuance of AD 2008-02-19 by the US Federal Aviation Administration (FAA) for Honeywell TFE 731 series engines, CASA assessed the directive and issued Australian AD/TFE 731/35, which became effective on 8 May 2008. This process underscores the importance of international cooperation in maintaining aviation safety standards and ensuring that all aircraft, regardless of where they are registered, meet the necessary safety criteria. In the case of this particular AD, it was issued due to Australia’s obligations under the Convention on International Civil Aviation and in response to a directive from the relevant State of Design. Consequently, there was no requirement for public consultation on this AD. Additionally, the Office of Best Practice Regulation has determined that ADs do not necessitate a Regulatory Impact Statement. This AD was made by the Acting Manager, Systems and New Technologies in the Airworthiness Engineering Branch, on behalf of CASA, in accordance with subsection 84A(2) of the Act. Failure to comply with the requirements set out in an AD can result in severe consequences. Under the Civil Aviation Act 1988, non-compliance with an AD may lead to both civil and criminal penalties. Specifically, section 97 of the Act provides for civil penalties, including fines and potential imprisonment, for violations of airworthiness regulations. The severity of the penalty depends on the nature and extent of the non-compliance, with maximum penalties often being significant, reflecting the critical nature of airworthiness requirements. Additionally, CASA has the authority to take enforcement actions such as grounding aircraft or imposing operational restrictions until compliance is achieved. These stringent measures are in place to ensure that all aircraft meet the highest safety standards, thereby protecting public safety and maintaining the integrity of the aviation industry.