COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES AMD Falcon 50 and 900 Series Aeroplanes AD/AMD 50/18 Frame 25 Water Drainage 13/99 Applicability: MF 900 S/n 1 to 177 and F900 EX S/n 1 to 41. Requirement: Modify in accordance with Dassault Aviation SB MF900-232 or F900EX-093 as appropriate. Note: DGAC AD 1999-446-028(B) refers. Compliance: Before 30 June 2000. This Airworthiness Directive becomes effective on 30 December 1999. Background: Manufacturer flight testing revealed that water does not drain properly through the Frame 25 filter and if it froze could lead to jamming of the flight controls.