Explanatory Statement
Civil Aviation Regulations 1988
Revocation of Airworthiness Directives
Legislation
Under section 98 of the Civil Aviation Act 1988, the Governor-General may make regulations for the purposes of the Act and in the interests of the safety of air navigation. Under regulation 39.001 of the Civil Aviation Safety Regulations 1998, CASA may issue airworthiness directives (ADs) for kinds of aircraft or aeronautical products. Subregulation 39.001(5) of the Civil Aviation Safety Regulations 1998 provides that an AD is a disallowable instrument for the purposes of section 46A of the Acts Interpretation Act 1901. Therefore, in accordance with section 6 of the Legislative Instruments Act 2003, an AD is a legislative instrument.
Under Annex 8 to the Convention on International Civil Aviation, the State of Design has overall responsibility for continuing airworthiness of an aircraft type, and must provide any information necessary to ensure the continuing airworthiness of a type to appropriate States of Registry. ADs (and their equivalents) are the most common form of continuing airworthiness information, and are issued by most ICAO Contracting States.
The State of Registry of an individual aircraft is responsible for its continuing airworthiness. Under Annex 8, the State of Registry must develop or adopt requirements to ensure the continuing airworthiness of aircraft. When a State of Design issues an AD against a type of aircraft on the Australian Register, CASA, as Australia’s national airworthiness authority, must assess that information and, if appropriate, issue an Australian AD to mandate the requirements of the State of Design.
State of Design ADs issued on or after 1 October 2009 are defined as ADs per Civil Aviation Safety Regulations Part 39.001A.
AD/B747/132
A State of Design airworthiness directive issued on or after 1 October 2009 is defined as an airworthiness directive per CASR Part 39.001A. The requirements of this airworthiness directive have been superseded by FAA AD 2010-21-04 issued on
7 October 2010.
AD/CT58/2
This unique Australian AD, issued in 1965, required the replacement of the stainless steel T bolt that connects the filter cover to the drive body on the purifier with a more ductile bolt, in accordance with General Electric CEB 73-41. As all engines should have been modified by now, the unsafe condition no longer exists and this AD is no longer required.
AD/CT58/3
This unique Australian AD, issued in 1966, required modification of the combustion casing assembly in accordance with General Electric CEB (CT58) 72-81 to avoid cracking of the casing skin around the adapter boss. As all engines would have been modified by now, the unsafe condition no longer exists and therefore the AD is no longer required.
AD/CT58/4
This unique Australian AD, issued in 1968, required inspection and modification of the compressor stator vanes in accordance with General Electric SB (CT58) 72-108. As all engines should have been modified by now, the unsafe condition no longer exists and the AD is no longer required.
AD/CT58/6
This unique Australian AD, issued in 1969, required the replacement of a hardened drive shaft pin in the fuel purifier in accordance with General Electric Alert Service Bulletin (CT58) A73-62. As all engines should have been modified by now, the unsafe condition no longer exists and this AD is no longer required.
AD/CT58/7
This unique Australian AD, issued in 1970, required a one-off inspection of the surface finish in the dovetail slot serrations and removal of any defective power turbine wheels in accordance with General Electric SB (CT58) 72-127. As all engines would have been inspected, the unsafe condition no longer exists and therefore the AD is no longer required.
AD/CT58/8
This unique Australian AD, issued in 1970, required the removal of defective detuner hose assemblies in accordance with General Electric SB (CT58) 73-63. As all defective hoses would have been removed, the unsafe condition no longer exists and the AD is no longer required.
AD/CT58/9
This unique Australian AD, issued in 1972 required inspection of the anti-icing air valve every 200 hours in accordance with General Electric SB (CT58) A75-22. As no defective anti-icing air valves have been reported to CASA over the last 30 years, it is evident that the unsafe condition no longer exists and therefore the AD is no longer required.
AD/CT58/10
This unique Australian AD, issued in 1976 required a one-off re-torque of the pinion gear bolt to a lower value and inspection for cracks of the mating backup washer in accordance with General Electric SB (CT58) A72-147. As all engines would have these requirements accomplished by now, the unsafe condition no longer exists and therefore the AD is no longer required.
AD/A320/184
A State of Design airworthiness directive issued on or after 1 October 2009 is defined as an airworthiness directive per CASR Part 39.001A. The requirements of this airworthiness directive have been superseded by EASA AD 2010-0209 issued on
14 October 2010.
AD/ARRIEL/35
A State of Design airworthiness directive issued on or after 1 October 2009 is defined as an airworthiness directive per CASR Part 39.001A. The requirements of this airworthiness directive which referred to EASA AD 2009-0184 have been superseded by EASA AD 2010-0215, effective 28 October 2010.
Consultation
No consultation with the Australian public has taken place on these AD cancellations. The Office of Best Practice Regulation has determined that ADs do not require a Regulatory Impact Statement.
The AD has been made by the Manager, Continuing Airworthiness in the Airworthiness and Engineering Branch, on behalf of CASA, in accordance with subsection 94 (1) of the Act.
[Instrument number CASA ADCX 027/10]