What was found
AFTER TAKEOFF, HAD BURNING SMELL IN CABIN LIKE OVENS, BUT OVENS WERE NOT ON, FELT A SIDEWAY KICK AND A LOUD BANG. DECLARED EMERGENCY. RETURNED TO CVG. NO ABNORMAL ENG INDICATIONS. ON RETURN, PASSENGER REPORTED SEEING A BAG SUCKED INTO AN ENG ON TAXI OUT. CHECKED INLET AND EXHAUST. REMOVED PLASTIC FROM FAN OF RT ENG. RAN ENG TO TAKEOFF POWER PER PFHB. ALL INDS NORMAL. REPLACED WATER SEPARATER BAGS DUE TO CABIN SMELL. ENGINE TOTAL CYCLES, 20,907.