What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
(-23) Owner/pilot departed cma at approximately 1335 in a flight of two for some formation type/sightseeing flying northwest bound. Upon initial power reduction engine began running rough. Rough turned into missing and increased vibration. An oil contamination light illuminated and decision was made to return to cma. Declared emergency to cma tower. Power continued to diminish and decision was made to divert to oxr. Loss of altitude proceeded and decision was further amended to land along Oxnard beach tree miles from approach end of oxr. Landed gear up without further incident. Damage to underside of fuselage appeared minor at time of incident. Propeller destroyed.
As the FAA filed it
(-23) OWNER/PILOT DEPARTED CMA AT APPROXIMATELY 1335 IN A FLIGHT OF TWO FOR SOME FORMATION TYPE/SIGHTSEEING FLYING NORTHWEST BOUND. UPON INITIAL POWER REDUCTION ENGINE BEGAN RUNNING ROUGH. ROUGH TURNED INTO MISSING AND INCREASED VIBRATION. AN OIL CONTAMINATION LIGHT ILLUMINATED AND DECISION WAS MADE TO RETURN TO CMA. DECLARED EMERGENCY TO CMA TOWER. POWER CONTINUED TO DIMINISH AND DECISION WAS MADE TO DIVERT TO OXR. LOSS OF ALTITUDE PROCEEDED AND DECISION WAS FURTHER AMENDED TO LAND ALONG OXNARD BEACH TREE MILES FROM APPROACH END OF OXR. LANDED GEAR UP WITHOUT FURTHER INCIDENT. DAMAGE TO UNDERSIDE OF FUSELAGE APPEARED MINOR AT TIME OF INCIDENT. PROPELLER DESTROYED.