What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
The pilot flew the aircraft from jefferson city - jefferson city memorial airport (jef), MO to columbia, MO - columbia regional airport (cou) earlier in the day without incident. He fueled at jef but not cou. The takeoff and climbout from cou were uneventful. At cruise, approximately 25 minutes after takeoff, the right engine started to run rough. Initially thinking it could be water contamination, he let it run for a minute. When it did not improve, he added more fuel to the mixture and that also did not help. The pilot then turned on the fuel boost pump to add pressure, but that did not help. He was switched over to stl approach control and declared an emergency and asked for vectors to the nearest suitable airfield. He was vectored to st. Clair regional airport (K39). The pilot shutdown the right engine and feathered the prop. He then made a single engine landing, stopped on the runway and shutdown the remaining engine. They were met on the runway by emergency vehicles and the aircraft was towed to the ramp. There were no injuries to the pilot or passengers.
As the FAA filed it
THE PILOT FLEW THE AIRCRAFT FROM JEFFERSON CITY - JEFFERSON CITY MEMORIAL AIRPORT (JEF), MO TO COLUMBIA, MO - COLUMBIA REGIONAL AIRPORT (COU) EARLIER IN THE DAY WITHOUT INCIDENT. HE FUELED AT JEF BUT NOT COU. THE TAKEOFF AND CLIMBOUT FROM COU WERE UNEVENTFUL. AT CRUISE, APPROXIMATELY 25 MINUTES AFTER TAKEOFF, THE RIGHT ENGINE STARTED TO RUN ROUGH. INITIALLY THINKING IT COULD BE WATER CONTAMINATION, HE LET IT RUN FOR A MINUTE. WHEN IT DID NOT IMPROVE, HE ADDED MORE FUEL TO THE MIXTURE AND THAT ALSO DID NOT HELP. THE PILOT THEN TURNED ON THE FUEL BOOST PUMP TO ADD PRESSURE, BUT THAT DID NOT HELP. HE WAS SWITCHED OVER TO STL APPROACH CONTROL AND DECLARED AN EMERGENCY AND ASKED FOR VECTORS TO THE NEAREST SUITABLE AIRFIELD. HE WAS VECTORED TO ST. CLAIR REGIONAL AIRPORT (K39). THE PILOT SHUTDOWN THE RIGHT ENGINE AND FEATHERED THE PROP. HE THEN MADE A SINGLE ENGINE LANDING, STOPPED ON THE RUNWAY AND SHUTDOWN THE REMAINING ENGINE. THEY WERE MET ON THE RUNWAY BY EMERGENCY VEHICLES AND THE AIRCRAFT WAS TOWED TO THE RAMP. THERE WERE NO INJURIES TO THE PILOT OR PASSENGERS.