What was found
CLT - FLT 8052 - ON CLIMB-OUT FROM CLT, THE NR1 ENGINE VIBRATION MONITOR INDICATED 2 UNITS ACCELERATING THROUGH 210 KNOTS. FLIGHT RETURNED TO FIELD AT CLT AND LANDED WITHOUT FURTHER INCIDENT. NO EMERGENCYWAS DECLARED. MAINTENACNE ACCOMPLISHED TROUBLESHOOTING PROCEDURE PER MM 71-00-00 PAGE 24Y AND PERFORMED JOB CARD J377-30-1 AVM SIGNAL CONDITIONER CHECK. ALL P ARAMETERS ARE WITHIN THE NO ACTION REQUIRED RANGE. AIRCRAFT OK FOR SERVICE. CL T - FLT 1531, LATER THAT DAY, FLT RETURNED TO FIELD A SECOND TIME AT CLT FOR SAM E ENGINE VIBRATION. AIRCRAFT WAS AT FL260 WHEN THE CAPTAIN DECIDED TO RETURN TOFIELD. FLIGHT LANDED WITHOUT INCIDENT. NO EMEREGNCY WAS DECLARED. (M)