COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Robinson R44 Series Helicopters AD/R44/9 Oil Line Elbows 6/98 Applicability: All R44 helicopters, serial numbers 0001 through 0330. Requirement: Remove any aluminium (blue-coloured) AN823-8D (45 degree) or MS20822-8D (90 degree) elbows that connect the A723 oil cooler lines to the engine accessory case and replace them with airworthy MS20823-8 (45 degree) steel elbows or MS20822-8 (90 degree) steel elbows, as applicable. Note: 1 FAA AD 98-05-10 Amdt 39-10371 refers. Note: 2 Robinson Helicopter Company R44 Service Bulletin SB-25, dated 01 October 1997 refers. Compliance: Unless previously carried out, within 50 hours time in service after the effective date of this Directive. This airworthiness directive becomes effective on 21 May 1998. Background: The manufacturer has received two reports of cracking of the aluminium elbows which connect the oil cooler lines to the engine accessory case. The helicopters experienced loss of engine oil, resulting in engine failure.