What happened
On June 26, 2022, a Piper PA-20-135, registration N1231C, was involved in an accident near Challis, Idaho. The flight was being operated under 14 CFR Part 91 for personal use. The aircraft departed from Lower Loon Creek airport (C53) during the evening hours.
A witness at the airport observed the aircraft take off and fly into a box canyon, noting a dust cloud shortly thereafter. Another witness, a friend of the pilot, reported that the crew had delayed their departure from C53 until later in the evening to avoid high density altitude issues. This witness observed the aircraft depart to the north, climb, and then turn back toward the runway on a southbound heading.
The aircraft impacted steep, rising mountainous terrain at an elevation of approximately 6,240 feet MSL, about 1.5 miles north of the airport. The impact occurred on a southerly heading. The wreckage was found upright, approximately 30 feet below the initial impact point, and was mostly consumed by fire. The pilot and passenger sustained 2 fatal injuries.
The investigation
Post-accident examination of the airframe and engine showed no mechanical anomalies that would have prevented normal operation. Flight control continuity was established from the cockpit to all primary controls, though several separations were noted in the flight control system, which were consistent with overload or the recovery process.
Investigators noted that the departure airport elevation was 4,200 feet MSL. Due to the 2,040-foot increase in elevation at the accident site, the aircraft's climb performance would have likely degraded from approximately 477 feet per minute to about 360 feet per minute. The calculated density altitude at the time of the accident was approximately 8,980 feet MSL.