Snow remaining on the wing of a Daher TBM 700N, marketed as the TBM 850, caused an aerodynamic stall and loss of control shortly after take-off near Pinedale, Wyoming, the NTSB has found. The aircraft briefly lifted off from Ralph Wenz Field on 29 October 2024 before its left wing dropped and struck the ground. The pilot’s failure to ensure the aircraft was clear of snow and to follow the manufacturer’s anti-icing procedure during continued snowfall was the probable cause.
The aircraft had stopped for about 15 minutes in heavy, wet snow. The pilot brushed it before departure, but a witness saw snow remaining on an outboard section of the wing. Snow continued as the aircraft taxied, allowing further accumulation. The NTSB concluded that contamination likely reduced lift and increased drag; its report does not quantify how much snow remained.
Type I and Type IV fluids were available at the airport, but the pilot declined them. Manufacturer guidance warned that Type I would provide inadequate protection during snowfall unless take-off followed de-icing almost immediately, and advised against using Type IV on this aircraft type.
The pilot reported rotating at 85 knots, below the approximately 87 knots indicated by the performance chart for the reported take-off weight. The NTSB identified the lower speed as a contributing factor. It found no pre-impact mechanical failure that would have prevented normal operation, and noted two previous accidents involving similar left-wing drops on the same aircraft type. The aircraft sustained substantial damage; one passenger was seriously injured, while the pilot and five other passengers sustained minor injuries.