Accident Sequence
The tow pilot preflighted the airplane, which had about one-quarter to one-third fuel capacity. The wind was from the west-northwest at 5–10 mph, and the flight departed from the westerly oriented runway while towing a glider. According to the glider pilot, after liftoff the tow pilot remained in ground effect, and the tow plane drifted left, striking the top of a small scrub oak about 15 ft high located approximately 1,000 ft before the end of the runway.
The glider pilot further stated that the accident pilot established a normal climb attitude at about 70 mph to about 250 ft above ground level. At that point, they encountered heavy sink/downdraft with turbulence that suddenly dropped them about 100 ft. Noting this condition, the glider pilot released the tow rope and terminated the tow. At that time, the glider pilot heard the Bucker's engine running and it sounded strong. The glider pilot then turned right, while the tow plane continued to drift and turn slightly left, toward a line of about 100-ft pine trees located about 1,000 ft from the end of the runway.
About 10 seconds later, the glider pilot observed the tow plane still in a climb attitude and in sink. The tow plane appeared to release the rope from the Bucker, then clipped the top of the tallest tree. It then seemed to snap roll to the left and into the ground.
Post-Accident Examination
Examination of the airplane at the accident site by an FAA inspector revealed no evidence of flight control preimpact failure or malfunction. The airplane was recovered, and a replacement propeller was installed for an engine run. The engine started and operated to an estimated 1,000 rpm but could not accelerate; impact damage was noted to the servo fuel injector (servo). Bench testing of the servo revealed no discrepancies related to fuel flow.