Cirrus SR22 N809SR accident near Grover, Utah

Probable cause

The pilot's encounter with moderate to severe icing conditions during cruise flight, which resulted in structural icing and a subsequent loss of control. Contributing to the accident was the pilot’s decision to continue a flight route through known moderate to severe icing conditions.

NTSB analysis

The pilot departed on an instrument flight rules cross-country flight and climbed to a cruise altitude of 14,000 ft mean sea level (msl). About 30 minutes into the flight, he requested a climb to 16,000 ft msl. Radar data indicated that over the next several minutes, the airplane climbed to 14,500 ft, then began an increasingly rapid descent as its groundspeed decayed from about 111 knots (kts) to about 64 kts before radar contact was lost. Witnesses reported that they heard the airplane and looked up to see it descending nose down like a corkscrew before it impacted terrain. Postaccident examination of the airframe and engine did not reveal any anomalies that would have precluded normal operation.

AIRMET Zulu for moderate icing conditions was valid for the area of the accident site at the time of the accident, and an atmospheric sounding supported the likely formation of moderate rime and mixed-type icing in the area. The sounding also indicated the potential for supercooled large droplet icing formation near the top of the cloud layer near 15,000 ft msl. Satellite imagery depicted cumulus and cumulus congestus type clouds with vertical development over the flight track and accident site, and weather radar imagery depicted the airplane entering an area of light-to-moderate intensity echoes just before radar contact was lost. Immediately before and after the accident, two other aircraft operating at similar altitudes reported encountering light clear to mixed icing conditions. The pilot had received preflight weather information containing the relevant forecasts and advisories. In addition, the airplane was equipped with a TKS ice protection system, but it was heavily fragmented during the accident sequence and the investigation was unable to determine if the system was activated or working at the time of the accident.

It is likely that, during the last minutes of the flight, the airplane encountered moderate-to-severe icing conditions, which adversely affected the airplane's handling characteristics and likely resulted in a loss of control.

Text from the NTSB. Open the NTSB docket for WPR19FA154 for the full record.