What was found
DURING TAKEOFF, THE FLIGHT CREW NOTICED WHAT SEEMED TO BE AN ELEC SMELL ALONG WITH SMOKE IN THE CABIN. THE CREW LEVELED OFF AT 2000’ & THEN RETURNED TO FIELD, WHILE DOING SO THEY TURNED THE AIR SOURCE OFF & RAM AIR ON, THIS QUICKLY CLEARED THE SMOKE. AN UNEVENTFUL LANDING WAS ACCOMPLISHED. AFTER TROUBLESHOOTING THE DISCREPANCY, FOUND THE AIR CYCLE MACHINE, PN 3471A020000, HAD SEIZED. THE ACM WAS REPLACED WITH AN INSPECTED & TESTED UNIT. LEAK & OPERATIONAL CHECKS WERE SATISFACTORY. ACFT WAS RETURNED TO SERVICE.