What was found
A LOUD BANG HEARD FROM RIGHT SIDE OF AIRCRAFT ON TAKEOFF FROM KFRG AT 600 FEET WHILE GEAR WAS GOING INTO WELL. CREW THOUGHT IT WAS A GEAR UPLOCK ISSUE. GEAR INSPECTED WITH NO DEFECTS FOUND. A FEW DAYS LATER AFTER ENGINE DATA DOWNLOADS IT WAS DETERMINED THE NR 1 ENGINE EXPERIENCED A COMPRESSOR STALL, ROLLBACK AND RELIGHT. A BOROSCOPE LATER DETERMINED DAMAGE TO THE ENGINE FROM A METCO LINING FAILURE, CAUSING EXTENSIVE DAMAGE TO THE COMPRESSOR, COMBUSTION, AND TURBINE SECTIONS. ENGINE REMOVED FOR MAINTENANCE.