Accident Overview
On August 17, 2011, at 1542 central daylight time, a Piper PA-31-310 multiengine airplane, registration N46TB, was substantially damaged following an explosion and fire before takeoff. The accident occurred at Perryton Ochiltree County Airport (PYX) in Perryton, Texas. The airplane was operated by the pilot under 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed, and no flight plan was filed. The pilot reported minor injuries.
Flight Details
The flight was intended to travel to Shawnee Regional Airport (SNL) in Shawnee, Oklahoma. After taxiing to the end of the runway, the pilot performed pre-takeoff cockpit checks with the engines running at 1,200 rpm. He reported an explosion under his seat that propelled his head into the ceiling, after which he saw flames inside the airplane. With both engines still operating, he immediately vacated the cockpit seat and exited through the cabin door. The unpiloted airplane began moving and came to a stop about 400 feet away, completely engulfed in flames. Firefighters arrived approximately 10 minutes later and extinguished the fire.
Pilot Background and Wreckage Examination
The pilot reported using either his airplane or personal vehicle in his role as a sales manager for a company that supplies chemicals to oil and gas drilling and production operations. He stated he was not transporting chemicals at the time of the accident.
An examination of the wreckage did not reveal any pre-accident malfunctions or anomalies that would have prevented normal operation. Investigators were unable to determine the source of the fire and explosion.
Damage
The airplane was substantially damaged by the fire.