What happened
On August 10, 2022, a Cirrus SR22, registration N379DH, departed Friday Harbor Airport (FHR) for a flight to Olympia, Washington. After takeoff, the aircraft climbed to approximately 1,100 feet MSL and proceeded south. ADS-B data and recovered flight recorder data from the aircraft's primary flight display (PFD) and multi-function display (MFD) indicate that the flight path became erratic during the final minutes of flight. The aircraft performed a right turn, a descent to 900 feet MSL, and a subsequent climb to 1,460 feet MSL.
At approximately 1459 PDT, the aircraft impacted heavily wooded terrain at an elevation of 1,286 feet MSL near Blyn, Washington. The impact occurred in a slightly nose-low attitude, and the aircraft came to rest inverted. The pilot sustained 1 fatal injury.
At the time of the accident, weather conditions near the impact site were within instrument meteorological conditions (IMC), characterized by an overcast cloud layer at 900 feet MSL and a fog bank approximately 700 feet above the ground.
The investigation
Engine data recovered from the MFD showed that engine power settings were varied during the flight, with the final recorded data point showing 2,680 RPM and 25.8 inches of manifold pressure. A physical examination of the engine revealed no evidence of mechanical failure that would have prevented normal operation. While cylinder No. 6 showed a high cylinder head temperature of 500°F during the flight, internal examinations showed no evidence of heat distress or catastrophic failure.
Investigators examined the aircraft's avionics and found that the PFD and MFD were likely non-functional. A maintenance representative reported that approximately one month prior to the accident, the pilot had presented the aircraft for inspection because the PFD showed an "internal power fail" and the MFD backlighting was non-functional, making the display "virtually impossible to see." No logbook entries were found indicating that these displays had been repaired or replaced.
An autopsy of the pilot identified dilated cardiomyopathy, though investigators determined a sudden incapacitating medical event was unlikely based on the flight data. Toxicology results showed the presence of doxepin, a sedating medication, as well as sildenafil, losartan, and amlodipine.
Findings
- The pilot continued to operate the aircraft despite known mechanical malfunctions with the flight displays.
- The pilot entered instrument meteorological conditions (IMC) that obscured terrain and reduced visibility.
- The aircraft struck trees and terrain while the pilot was maneuvering to exit the deteriorating weather.