Accident Overview
On August 11, 2019, at approximately 1128 Pacific daylight time, an experimental Lancair IV, registration N350CL, was destroyed when it struck terrain near Kooskia, Idaho. The private pilot and one passenger were fatally injured. The flight was operated under 14 Code of Federal Regulations Part 91 as a personal flight.
Flight History
According to flight track data, the airplane departed Polson Airport (8S1) in Polson, Montana, at about 0950. It flew southwest at altitudes between 10,500 and 10,800 feet mean sea level (msl). At 1019, about 26 miles from the accident site, it turned south for approximately 4 minutes, then turned right to the southwest at about 16 miles from the site. At 1027, the airplane entered a climb, reaching a peak altitude of 13,500 feet msl, and its groundspeed decreased to 79 knots. It then entered a left descending turn toward the accident area. The pilot was not in contact with air traffic control during the flight.
Witness Accounts
A local resident driving near the accident site around the time of the accident described the weather as “nasty,” with heavy rain and lightning. He saw a flash of light and heard an explosion, initially thinking it was a lightning strike. He later learned it was the airplane impacting terrain; he did not see the aircraft. Another witness, fishing nearby, reported heavy rain and frequent lightning. He heard the airplane’s engine revving up and down, as if straining, but did not hear or see the impact.
Weather Conditions
Weather radar imagery showed light to heavy precipitation moving northeast over the accident area near the time of the accident. Half-inch hail was detected about 15 minutes before the crash. Heavy precipitation was observed well above 30,000 feet msl. Rawinsonde data indicated potential for icing above 14,000 feet. Maximum vertical velocity was calculated at about 6,300 feet per minute, and downdraft convective available potential energy (CAPE) was 317 Joules per kilogram. An AIRMET advisory for mountain obscuration was active below 17,000 feet, and a Convective SIGMET was valid for the area at the time.
Pilot Information
Federal Aviation Administration records show the pilot held a private pilot certificate with ratings for airplane single-engine land and sea, instrument airplane, and glider. He reported 4,620 hours of flight experience and 35 hours in the previous 6 months as of his last medical exam on February 15, 2016. His most recent logbook recorded 18.9 hours in the 10 months before the accident, including 28 instrument approaches but no simulated or actual instrument time.
Wreckage and Engine Examination
The accident site was on an east-facing slope, about half a mile uphill from the Clearwater River and 3 miles east of Kooskia. The debris field was about 180 feet long and 100 feet wide, oriented on a magnetic heading of about 94°. All major structural components and flight controls were present. Flight control continuity could not be established due to extensive impact and thermal damage. A detailed engine examination found no evidence of preexisting malfunctions or failures that would have precluded normal operation.
No Contact with Flight Services
According to Leidos Flight Service (LFS), neither LFS nor any third-party vendors using their system had any contact with the pilot regarding the accident flight.