COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Eurocopter AS 350 (Ecureuil) Series Helicopters AD/ECUREUIL/46 Tail Rotor Drive Shaft Bearings 11/91 DM Applicability: All AS 350 helicopters versions B, D, B1, B2, L1 and AVEX equipped with P/N P.9107.NPP7 FAFNIR tail rotor drive shaft bearings not marked with an "X" on the seal flange. Requirement: Action in accordance with the Technical Requirements of DGAC AD 91-159-060 (B) for all aircraft acceptance tested by Aerospatiale Marignane between 15 May 1991 and 20 July 1991 or prior to 15 May 1991 and have operated less than 100 hours time in service. Note: Aerospatiale Telex Service No. 01-34 refers. Compliance: By 30 August 1991 or prior to issue of Australian C of A, whichever occurs first. Background: Corroded bearings which could seize may have been fitted to the tail rotor drive shaft.