Accident Sequence
The pilot of the towplane reported a normal takeoff. While climbing through 600 feet above ground level, he initiated a turn to the east. As the airplane turned, he felt the glider release. Witnesses observed that when the towplane turned left, the glider did not follow; instead, it continued straight ahead and began climbing. Subsequently, the glider entered an uncoordinated turn to the right, toward the airport. The glider's nose then dropped, and it entered a spin before impacting the ground.
Tow Rope Examination
After the towplane landed, it was determined that the tow rope had separated. The glider pilot had not released in the normal manner. The 5/16-inch polypropylene rope separated at a point 25 feet forward of the glider attach point. The fibers at the separation point were frayed and uneven. The remainder of the rope was clean and free of abrasions, knots, and nicks.
Toxicological Findings
Toxicology tests detected 0.034 µg/ml of diphenhydramine in the pilot's blood, and an unquantified amount in his urine. Diphenhydramine is an over-the-counter antihistamine. A study on diphenhydramine concluded that it adversely affects a person's ability to maneuver an automobile.