Pilot Statement
The pilot stated that just after takeoff, the airspeed began decreasing, the stall warning horn sounded, and the airplane started sinking despite corrective actions. The airplane impacted the ground beyond the departure end of the runway.
Environmental Conditions
Density altitude was 6,385 feet. The pilot took off uphill to the south; the average runway slope was 0.81 percent.
Video Evidence
A videotape filmed by a rear-seat passenger showed that the aircraft reached a pitch attitude of up to 24 degrees nose-high after takeoff. The recording also captured a sound resembling the stall warning horn 42 seconds after the start of the takeoff roll, which was approximately 18 to 19 seconds after becoming airborne. No significant change in engine noise pitch was recorded during the event.
Runway Slope Information
The FAA's regional airport master record and the Utah state aeronautical chart inaccurately indicated that the runway sloped uphill to the north, rather than to the south. The Airport/Facility Directory (A/FD) provided no runway slope data for the airport; the A/FD legend stated that runway slope would be shown only when it is 0.3 percent or more.
Post-Accident Findings
During post-accident functional testing, the airplane's electrical flap switch demonstrated improper mechanical operation attributed to normal wear.