What was found
PER PILOT REPORT: UPON IMMEDIATELY DEPARTING THE AIRFIELD, THE TWO CREW MEMBERS IN THE REAR OF THE AIRCRAFT STATED THAT THEY SMELLED SOME KIND OF SMOKE. UPON HEARING THE AFOREMENTIONED INFORMATION, I IMMEDIATELY EXECUTED A 180 DEGREE TURN TOWARD THE LANDING AREA IN WHICH WE HAD JUST DEPARTED. AT NO TIME DID I OR MY LEFT SEATED CREWMEMBER SMELL ANYTHING ABNORMAL. ALSO, THERE WERE NO INDICATIONS IN THE COCKPIT OR CAUTION ADVISORY PANEL. MX ACTIONS: FOUND COMPRESSOR HAD SEIZED, AND AC BELT HAD SNAPPED. BOTH ITEMS FOUND FAULTY HAVE SINCE BEEN CHANGED TO INCLUDE TO HOSES.