As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRPLANE HAD SHALLOW VIBRATION INFLIGHT. VIBRATION INCREASED WITH AIRSPEED. AN EMERGENCY WAS DECLARED AS A PRECAUTION. LANDING WAS UNEVENTFUL. DURING POST FLIGHT, FOUND BOTTOM PORTION OF RIGHT THRUST REVERSER TO BE DEPLOYED APPROXIMATELY A 1/2 INCH.