Accident Summary
Shortly after takeoff, a loud noise was heard in the cockpit followed by severe engine vibrations. The pilot determined that a return to the airport was not possible and executed a forced landing in an open salt marsh, approximately 3.5 miles southwest of the closest airport. During the landing rollout, the landing gear dug into the soft ground, causing the airplane to nosed over and come to rest inverted.
Initial Findings
A visual inspection of the airframe revealed no traces of oil on the belly. Examination of the engine showed the turbocharger was oil soaked. The number 5 cylinder exhibited a circular crack around the head, with a red discoloration on the top portions of the cylinder fins.
Engine Examination
The engine was disassembled for further investigation. The number 5 connecting rod had separated at the crankshaft rod journal. A high-pressure air source was used to check for blockage of oil galleys and passages. The number 5 crankshaft rod journal oil port was found blocked with smeared metal; no additional blockages were found. About 2 to 3 quarts of oil were drained from the oil sump, along with portions of the number 5 connecting rod, pieces of piston and piston rings, and the intake and exhaust lifters for the number 5 cylinder.