What was found
NR 1 ENGINE SHUTDOWN IN FLIGHT AND RETURNED TO MIAMI DUE TO 2.5 SPIKE ON VIBRATION, BOTH CHANNELS IN THE LOW RANGE. REMOVED AND INSPECTED MASTER INTERNAL GEARBOX CHIP DETECTORS IAW 72-01-00, NO EVIDENCE OF INTERNAL FAILURE FOUND. VISUALLY INSPECTED AIR INLET LOW PRESS COMPRESSOR AND EXHAUST, NO EVIDENCE OF FOD. CLEANED AND LUBRICATE CLAPPERS IAW MM 72-31-05. PERFORMED VIBRATION SURVEY TEST NR 11 IAW 71-00-00 VIBRATION WITHIN LIMITS CHECK OK.