Witnesses stated that the airplane became airborne after a short takeoff roll and lifted of before reaching taxiway 'F.' They added that the airplane was established in a very steep climb attitude, as soon as it became airborne. Subsequently, it nosed down and impacted on the west edge of runway 16R, between taxiway 'F' and runway 10. Examination of the wreckage by an FAA inspector revealed that the elevator trim was in the full nose up position. The trim indicator confirmed the position of the elevator trim.