CIVIL AVIATION ACT 1988
CIVIL AVIATION SAFETY REGULATIONS 1998
ISSUE OF AIRWORTHINESS DIRECTIVE
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.
In this case, the state of design (The FAA) did not choose to raise an AD to address the unsafe condition despite intense lobbying by CASA, but the European Aviation Safety Authority (EASA) raised an AD earlier this year to replace the blades.
In line with EASA’s action, CASA has raised AD/R22/53 to correct the unsafe situation on R22 helicopters. This AD mandates the replacement of P/N A016-2 main rotor blades with the improved design P/N A016-4 blade. The effect will be to mandate the manufacturers Service Bulletin SB-94, which strongly recommends replacement of P/N A016-2 blades with P/N A016-4 blades. It is aimed at addressing a serious safety problem that can result when internal cracking originating from the blade root fitting inboard bolt hole leads to catastrophic fatigue failure of the main rotor blade. Three fatal accidents in Australia were caused by this internal cracking problem.
CASA has consulted extensively with the Australian industry and public via a Notice of Proposed Rule Making (NPRM 0503CS) and a Notice of Final Rule Making (NFRM 0503CS). After considering the comments received, CASA has decided to proceed with raising this AD.
The Office of Regulatory Review has determined that ADs do not require a Regulatory Impact Statement.
The AD has been made by the General Manager, Manufacturing, Certification and New Technologies Office, on behalf of CASA, in accordance with subsection 84A (2) of the Act.