As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT NR 6486 - JFK-IAD - DURING CRUISE, MADE UNSCHEDULED LANDING DUE TO PROP VIBRATION. AIRCRAFT RETURNED TO GATE WITH NO FURTHER INCIDENT. MAINTENANCE REMOVED ICE FROM SPINNER AND PERFORMED GROUND RUNS. AIRCRAFT WAS RELEASED AND APPROVED FOR RETURN TO SERVICE. (M)