What was found
DURING TAKEOFF ROLL, PASSENGERS REPORTED A FLASH AND FLAME BALL FROM LEFT WING. ALSO, TOWER REPORTED HEARING A LOUD NOISE. TAKEOFF WAS ABORTED AT 80 KNOTS. CREW SUSPECTED NR 1 ENGINE COMPRESSOR STALL BUT REPORTED NO ABNORMAL INDICAITONS. MAINTENANCE INSPECTED ENGINE PER MM 71-00-00 AND RAN ENGINE TO FULL POWER. NO DEFECTS WERE NOTED. BORESCOPE DEFERRED FOR 5 CYCLES. EXACT PART CAUSING PROBLEM TO BE DETERMINED.