What was found
PILOT REPORTED SUDDEN SEVERE VIBRATION APPROXIMATELY 20 MINUTES INTO FLIGHT FOLLOWED WITHIN 1-2 MINUTES BY COMPLETE LOSS OF OIL PRESSURE TO ZERO. APPROXIMATELY 6 MINUTES TO LANDING WITH RISE IN OIL TEMP OFF SCALE, INCREASED VIBRATION, BURNING ODOR AND PROGRESSIVE POWER LOSS. HAD NORMAL RECENT FLIGHTS, NORMAL START, RUN-UP, AND INITIAL FLIGHT BEFORE PROBLEM STARTED. BRIEF INSPECTION AFTER LANDING DID NOT IDENTIFY PROBLEM, ALTHOUGH THERE WAS A LARGE AMOUNT OF OIL ALONG BELLY AND SOME ON PROP. MECHANICS CURRENTLY WORKING TO ASCERTAIN PROBLEM.