The single-engine airplane overran the departure end of runway 10 while landing on a 1,900-foot long, by 100-foot wide grass airstrip. The 1,240-hour commercial pilot reported on NTSB Form 6120.1 that he flew the airplane at "70 knots, and upon touchdown, didn't get on brakes right away." The pilot added that "when I did it was too late, I slowed to about 10 MPH and ran-off the runway, down an embankment, and flipped-over." In the recommendation section marked "How could this accident have been prevented?" the pilot stated "I should have landed at '60' or '65' and got on the brakes right away." The pilot was able to egress the aircraft unassisted. No mechanical anomalies or discrepancies were reported. Two individuals witnessed the landing at the airstrip. One eyewitness recalled that the aircraft appeared to be traveling "fast" and touched down near "half the length of the runway" or approximately 950 feet. Another eyewitness reported that the airplane appeared to touch down smoothly, but at a fast rate of speed. This eyewitness continued to observe the roll-out noticing that the aircraft did not appear to decelerate after touching down and he observed the airplane overrunning the departure end of the runway into the terrain. The airfield manager described the condition of the grass airstrip as "well-maintained and dry" at the time of the mishap. The winds at the time of the accident were reported from 330 degrees at 11, gusting to 18 knots.