What happened
On July 13, 2010, a Beechcraft BE-35-C33, registration N5827S, crashed into terrain in Tolar, Texas. The flight departed from Clark Municipal Airport in Stephenville, Texas, at approximately 2120, bound for Arlington Municipal Airport. The aircraft was being operated by a commercial pilot accompanied by two passengers.
Prior to the accident, the aircraft had flown from Arlington to Stephenville for a meal. During the return leg of the flight, radar data showed the aircraft traveling northeast at an average altitude of 3,400 feet. GPS data recovered from the wreckage indicated that between 2128 and 2129, the aircraft performed a series of turns, including a left turn followed by a right turn that resulted in a descent.
A witness near the crash site observed the airplane flying low over trees, approximately 600 feet above the ground, in a clockwise circling pattern. The witness reported that the aircraft suddenly "nose dived" into the ground with its wings nearly vertical.
The impact resulted in 3 fatal injuries for the pilot and the two passengers.
The investigation
Investigators examined the wreckage and found the aircraft had sustained substantial damage. The engine had separated from the airframe and came to rest inverted. An examination of the engine, including the fuel control unit, fuel nozzles, and internal mechanics, revealed no pre-impact mechanical deficiencies. The fuel selector was set to the right wing tank, and the elevator trim tab was positioned 10 degrees nose down.
Data from a handheld Garmin GPSMAP 295 unit was successfully downloaded and reviewed. Toxicology testing performed on the pilot detected low levels of marijuana metabolites in the blood, lung, and urine; however, these levels were consistent with use in the days or weeks prior to the accident and were not indicative of impairment at the time of the crash.
Findings
- The pilot's actions were consistent with experiencing a vestibular illusion.
- The aircraft entered a descending spiral from which the pilot was unable to recover.
- The accident occurred during a night flight over a rural area under visual meteorological conditions.