What happened
On June 27, 2023, at approximately 0759 mountain daylight time, a Curtiss Wright P-40E, registration N4420K, was involved in a fatal accident near Hamilton, Montana. The aircraft was operating under Part 91 for personal use.
Prior to departure from Ravalli County Airport (HRF), the pilot had consulted a mechanic to troubleshoot a starter issue. After the inspection, the pilot successfully started the engine and proceeded with pre-takeoff checks. During the engine run-up at the hold-short line for runway 35, a mechanic observed a 3-5 second engine surge.
Following takeoff, witnesses observed the aircraft climbing to the north before turning left toward the west. During this initial climb, multiple witnesses reported a loss of engine power. The aircraft subsequently descended and impacted terrain approximately 1/2 mile west of the departure end of runway 35 in a nose-down attitude. The impact resulted in 1 fatality and substantial damage to the aircraft.
The investigation
An examination of the wreckage showed the debris path spanned approximately 216 feet on a heading of 230° magnetic. The fuselage came to rest upright at an elevation of 3,615 feet mean sea level.
Investigators confirmed flight control continuity from the cockpit to all control surfaces. A post-accident examination of the engine and airframe revealed no mechanical anomalies that would have prevented normal operation. While the engine could not be placed on a test stand due to impact and thermal damage, manual rotation of the crankshaft via the reduction gear confirmed mechanical continuity throughout the rotating group, valvetrain, and accessory section. Damage to the propeller blades suggested the engine was producing low to no power at the time of impact.
Postmortem toxicological testing of the pilot detected Citalopram, N-Desmethylcitalopram, Albuterol, and Rosuvastatin. An FAA medical case review noted that the pilot had been successfully managing his condition with Citalopram since 2014, with documented follow-ups and evaluations in his medical certification file.