This August 2009 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.
Aircraft: Piper Pawnee. Injuries: 1 Fatal. Location: Creswell, Ore. Aircraft damage: Destroyed.
What reportedly happened: The airplane was being used to tow gliders. Shortly after the plane with a glider in tow departed, witnesses reported that the glider moved ahead of the tow airplane as the tow airplane descended. Witnesses reported that the Piper appeared to be slow and, approximately 200 feet above the ground, abruptly nosed over and crashed into terrain.
The student pilot of the glider reported that the takeoff roll, lift off and climb to 200 feet was normal. He stated that shortly after the glider reached 200 feet he heard a loud bang and glanced over his right should to find the rear door unlatched. As he looked back he noted that the glider was now above the normal tow position. The glider pilot pushed the stick forward to maneuver the glider to the proper tow position. The glider pilot noted slack in the tow line, and stated the tow airplane descended below the glider to a point where he lost sight of the airplane. He stated that the tow airplane did not seem to be in distress or out of control, and appeared to be in a 10° nose-down attitude prior to release. The glider pilot released from the tow airplane, turned 180° back towards the airport, and landed without further incident. He stated that the release felt normal, the glider did not pitch up or down, and no abnormal yaw was noted.
Examination of the tow airplane tail hook assembly revealed that the mounting plate was bent upward and the heads of two connecting bolts were in contact with the base of the rudder. The tail hook was intact and remained attached to the mounting plate. The hook was in the locked position, closed around the tow ring. The release cable remained attached to the hook and was continuous to the cockpit release handle. Functional testing of the tail hook assembly revealed no anomalies, and the assembly functioned appropriately.
Examination revealed no evidence of mechanical malfunction or failure with the engine or airframe.
Toxicology testing indicated the presence of marijuana in the tow pilot’s blood and lung tissue. The levels of marijuana noted in the toxicology report suggest use of the illegal drug within three hours of the accident, which likely impaired him during the flight.
Probable cause: The pilot’s failure to maintain aircraft control during takeoff for a glider tow operation. Contributing to the accident were his impairment due to marijuana use and the low altitude of the flight that reduced the time available to recover from an upset.
For more information: NTSB.gov NTSB Identification: WPR09FA414