NTSB Factual Report

On September 29, 2001, at 1700 central daylight time, a Cessna 414 Riley Super-8, N414NG, piloted by a commercial pilot, was destroyed on impact with terrain and fire near Marshfield Municipal Airport (MFI), Marshfield, Wisconsin. A report of a partial power loss on one engine was made to ATC during the en route phase of flight. Visual meteorological conditions prevailed at the time of the accident. The 14 CFR Part 91 flight was operating on an instrument flight rules flight plan. The pilot, pilot-rated passenger, and one other passenger were fatally injured. The flight departed from Alexander Field South Wood County Airport (ISW), Wisconsin Rapids, Wisconsin, en route to Poplar Bluff Municipal Airport (POF), Poplar Bluff, Missouri.

For full narrative please go to http://www.ntsb.gov/aviation/CHI01FA329_Factual_Narrative.pdf

NTSB Probable Cause

The pilot's failure to maintain adequate airspeed (Vmc) which resulted in a loss of control. Contributing factors were the improper in-flight planning/decision not to land at a closer airport and the lack of recent experience in multiengine airplanes by the pilot-in-command, the cylinder head separation, the inadequate manufacturing process, and the lack of continued airworthiness instructions relating to the Riley Super-8 STC.