COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Bombardier (Canadair) CL-600 (Challenger) Series Aeroplanes AD/CL-600/27 Rudder Control Quadrant 3/95 Amdt 1 DM Applicability: MODEL SERIAL NUMBER CL-600-1A11 1004 through 1085 CL-600-2A12 3001 through 3066 CL-600-2B16 5001 through 5147 CL-600-2B19 7003 through 7038 Requirement: 1. Perform an ultrasonic inspection of the rudder quadrant, part number 600-92614-1 (original quadrant) or 600-92614-3 (quadrant modified with undercut), for cracks at the inside root radius of the spigot in accordance with the following service bulletins: 1. For CL-600-1A11, -2A12 and -2B16 aircraft: Accomplishment Instructions Part A of the applicable Canadair Challenger Service Bulletins 600-0637 Revision 1 or 601-0426 Revision 1. b. For CL-600-2B19 aircraft: Accomplishment Instructions of Canadair Regional Jet Alert Service Bulletin A601R-27-011 Revision A. Alternatively, the above inspection may be performed with the fluorescent penetrant method if the quadrant assembly is first removed from the aircraft. If cracks are found in the quadrant, modify the rudder quadrant assembly in accordance with Requirement 2 of this Directive. Note: Rudder quadrants, part number 600-92614-1 and 600-92614-3, are part of rudder quadrant assemblies, part number 600-92619-1 and 600-62619-5, respectively. 2. Modify the rudder quadrant assembly, part number 600-92619-1 or 600-92619-5, in accordance with the following service bulletins: 1. For CL-600-1A11, -2A12 and -2B16 aircraft: Accomplishment Instructions Part B of the applicable Canadair Service Bulletin 600-0637 Revision 1 or 601- 0426 Revision 1. b. For CL-600-2B19 aircraft: Accomplishment Instructions of Canadair Regional Jet Service Bulletin 601R-27-015 Revision A. Note: Transport Canada AD CF-94-23 refers. Compliance: 1. Unless Requirement 2 is already accomplished, prior to 28 February 1995. 2. Prior to 30 June 1995. COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES Background: There has been one instance of an in-flight failure of a rudder control quadrant P/N 600-92614-1. The failure was caused by stress corrosion cracking and resulted in partial loss of rudder control. Amendment 1 is issued to introduce modification action as required by Transport Canada.