What was found
AIRCRAFT WAS GROUNDED: PILOT REPORTS DURING CRUISE IN THE WEATHER WITH ICING CONDITIONS WE HAD DUEL CADC FAILURE. BOTH AUTOPILOTS WOULD NOT ENGAGE. AIRSPEED AND FLIGHT INSTRUMENTS WERE OK. LEFT THE WEATHER AND EVERYTHING CAME BACK NORMAL. MAINTENANCE REPLACED NR 1 AND NR 2 CADCS IAW AMM 34-16-01, OPS CHECKED NORMAL. LEAK TESTED PITOT STATIC SYS IAW AMM 34-16-00 AND RTS 22-01-05. REMOVED AND REPLACED CAPT AND FOS PITOT TUBES IAW AMM 34-11-02. OPS CHECKED NORMAL. LEAK CHECKED IAW AMM 34-11-00-201. REMOVED AND REPLACED AUX PITOT TUBE IAW AMM 34-11-02. OPS CHECKED NORMAL.