What happened
During a personal flight, a single-engine turboprop aircraft carrying a pilot and three passengers crashed shortly after departing from an airport. The flight was part of a round trip, as the pilot had previously completed a successful one-hour flight earlier that day. During the takeoff phase of the return leg, the aircraft struck wooded terrain located approximately 0.5 miles northwest of the runway's departure end. No witnesses observed the impact, and the pilot's final radio communications with flight service and on the common traffic advisory frequency were routine, with no distress signals sent prior to the crash.
Following the impact, a post-crash fire destroyed a large portion of the wreckage. There were 4 fatalities and no survivors.
Findings
Investigators examined the wreckage for mechanical failures and found no evidence of pre-impact malfunctions. While an inspection of the propeller revealed that a reversing lever guide pin had been installed backward—a condition that could potentially cause uncommanded blade feathering—the carbon block remained in place and the propeller was operating within its normal range at the time of the accident. This error was likely not a contributing factor, especially as the propeller had been correctly installed during the last annual inspection 100 flight hours prior.
However, medical examinations of the pilot revealed severe coronary artery disease, including significant stenosis in both the right and left anterior descending arteries, along with mitral annular calcification. These conditions placed the pilot at a high risk for an acute cardiac event, such as a heart attack or arrhythmia. It is concluded that an acute cardiac event likely caused sudden impairment or loss of consciousness, leading to the loss of control of the aircraft.