Crash of a Cessna T207 Skywagon in Grand Canyon
Date & Time:
Apr 13, 1990 at 1458 LT
Registration:
N91081
Survivors:
Yes
Schedule:
Grand Canyon - Grand Canyon
MSN:
207-0062
YOM:
1969
Crew on board:
1
Crew fatalities:
Pax on board:
6
Pax fatalities:
Other fatalities:
Total fatalities:
0
Captain / Total hours on type:
9.00
Aircraft flight hours:
5325
Circumstances:
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.
Probable cause:
Improper adjustment of the turbocharger absolute pressure controller, and improper manipulation of the power plant controls by the pilot during the go-around. Factors related to the accident were: failure of company management to properly train the pilot in accordance with the approved company training program, and the pilot's lack of experience in turbocharged engine operations.
Final Report:
