What was found
DURING TAKEOFF ROLL IMMEDIATELY PRIOR TO ROTATION, CREW HEARD A POP, F/O FELT AND IMPACT UNDER HIS FEET. BURNED RUBBER SMELL IN COCKPIT LASTED 5 MINUTES AND GEAR RETRACTION WAS NORMAL. NO GEAR WARNING OR OTHER ABNORMAL INDICATIONS WERE NOTED. PERFORMED ABNOMRAL NOISE CHECK, INSPECTED RADOME, NOSE W/W, FWD AND AFT E AND E BAYS, WING LEADING EDGES AND FUSELAGE LOWER SKIN AND NO ABNORMALITIES WERE FOUND. ABNORMAL NOISE CHECK PERFROMED IAW DHL B727 MM 5-51-311.