Crash of a Cessna T207 Skywagon in Grand Canyon

According to witnesses, the aircraft was about to touchdown from a normal approach to runway 21, when it encountered variable wind conditions and ballooned to about 70 feet agl. The pilot initiated a go-around. Shortly thereafter, witnesses observed a puff of smoke emanate from the aircraft, then the pilot transmitted that the flight was 'going down.' Subsequently, the aircraft collided with trees on wooded terrain about 1/2 mile from the departure end of the runway. An examination revealed a lack of power signatures on the propeller; evidence of sooting was found on the spark plugs (indicating a rich mixture). Testing of the turbo-controller revealed evidence that it had been adjusted to a low setting; the turbo would only produce a maximum air flow equal to high cruise power. The engine manufacturer reported that this situation could produce an over-rich mixture, particularly if the throttle and/or mixture controls were improperly manipulated. The pilot lacked experience in aircraft with turbocharged engines and he was not trained in accordance with the company training program.