What was found
NR 1 ENGINE FAILED DURING T/O RUN. LOUD BANG FROM LEFT SIDE OF A/C HEARD, T/O ABORTED AT 50 KNOTS. A/C REPORTED SMOKE AND FIRE. BLEW NR 1 FIRE BOTTLE AND SHUT DOWN ENGINE. NO EVIDENCE OF FIRE FOUND DURING INSPECTION. CHANGED ENGINE, METAL FOUND IN BLEED VALVE.