What was found
DFW - FLT 1446 - AT 1235Z, FL250, HAD A BURNING SMELL IN COCKPIT. LASTED ABOUT 30 SECONDS, THEN DISSIPATED. REOCCURRED, DECLARED EMERGENCY AND LANDED DFW WITHOUT FURTHER PROBLEMS. REPLACED LEFT PACK RECIRCULATING FAN. SYSTEM GROUND CHECK NORMAL OPERATION. (M)