HISTORY OF FLIGHT On July 28, 2007, at 2131 Pacific daylight time, a Mooney M20E airplane, N9302M, sustained substantial damage following a loss of control during a go-around maneuver and subsequent collision with terrain at the Tonasket Municipal Airport, Tonasket, Washington. The commercial pilot and pilot rated passenger were killed. The airplane was registered to, and operated by the pilot as a visual flight rules (VFR) personal cross-country flight under Title 14, CFR Part 91, when the accident occurred. Visual meteorological conditions prevailed for the flight that originated at the Dorothy Scott Airport, Oroville, Washington, approximately 15 minutes prior to the accident. Tonasket was the pilot's intended destination and no flight plan was filed. A witness, who was located at the airport approximately 50 feet from the runway, stated the airplane approached from the south and touched down well beyond the midpoint of runway 33. The witness reported the airplane began to accelerate stating "I am sure she thought she would overrun the runway so she accelerated to take off and make a second approach." Approximately .25 miles off the departure end of the runway, at an estimated altitude of 250 feet above ground level (agl) the airplane rolled left and subsequently impacted terrain in a nose-low attitude. The accident flight was one leg of a multi-day, multi-flight trip from Alaska to the pilot's home airport in Placerville, California. PERSONNEL INFORMATION The 78 year old pilot held a commercial pilot certificate with airplane single-engine land and instrument airplane ratings. The pilot's most recent third-class medical certificate was issued on August 16, 2005, and contained a limitation stating "must have corrective lenses available for near vision." The pilot listed 5,500 hours total flight time, and 50 hours total flight time in the 6 months preceding the medical application. AIRCRAFT INFORMATION The single engine Mooney M20E, serial number 1235, was manufactured in 1966, and was certified as a normal category airplane. The four-place, retractable landing gear airplane was equipped with a Lycoming IO-360 engine rated at 200 horsepower. The airplane's maximum gross takeoff weight was listed as 2,575 pounds. Airframe, engine and propeller maintenance records for the airplane were not located. METEOROLOGICAL INFORMATION The closest weather observation facility to the accident site was the Omak Airport (KOMK), located approximately 15 nautical miles (nm) south of the accident location at an elevation of 1,305 feet mean sea level (msl). The following Meteorological Aerodrome Report (METAR) was issued during the period of the accident: At 2153, the METAR observation was, in part, wind from 140 degrees at 4 knots, visibility 10 statute miles, clear sky, temperature 26 degrees C. According to U.S. Naval Observatory Astronomical Data for the accident site area, sunset occurred at 2103, and the end of civil twilight occurred at 2119. A witness to the accident reported the weather was clear and the winds were calm. He reported the moon was full and it was "…still light enough to see well." AIRPORT INFORMATION The Tonasket Municipal Airport (KW01) is located approximately 2 nm northwest of Tonasket, Washington. The airport has a single asphalt runway (33/15) that is 3,053 feet in length and 50 feet wide. The airport elevation is 1,311 feet msl. The runway is equipped with medium intensity runway lights (MIRL), and a 2 box, 4.5-degree Visual Approach Slope Indicator (VASI). The U.S. Government Airport/Facility Directory (A/FD) indicated the VASI was out of service at the time of the accident. WRECKAGE AND IMPACT INFORMATION The aircraft impacted terrain approximately 3,000 feet beyond the departure end of the runway. The airplane sustained substantial damage as a result of impact forces and postcrash fire. MEDICAL AND PATHOLOGICAL INFORMATION An autopsy was performed on the pilot on July 30, 2007. According to the autopsy report, the cause of death was "Multiple Internal Injuries due to Blunt Impact to the Head, Trunk and Extremities." The FAA's Civil Aerospace Medical Institute, Oklahoma City, Oklahoma, performed forensic toxicology tests on specimens from the pilot. The report stated Diphenhydramine, .081 ug/ml, was detected in the blood specimens. Diphenhydramine (commonly known by the trade name Benadryl) is an over-the-counter antihistamine with sedative effects, often used to treat allergy symptoms or as a nighttime sedative. ADDITIONAL INFORMATION Postaccident examination and teardown of the airframe and engine revealed no evidence of a mechanical malfunction or failure prior to impact.