What happened
While performing an approach toward Lewiston Airport, Idaho, the pilot encountered deteriorating weather conditions. In response to the inclement weather, a decision was made to divert the flight to Pullman-Moscow Airport. However, that alternate destination was also unavailable for arrival due to ongoing severe weather.
During the subsequent approach amidst falling snow, the aircraft struck a ridge situated approximately half a mile north of the airport. The impact resulted in the total destruction of the aircraft and the death of the pilot, who was the only person on board at the time of the accident.
Findings
The investigation identified several critical factors contributing to the crash, primarily centered around improper IFR operation during the final approach. Several environmental and operational elements were noted:
- Extremely low visibility, measured at one-half mile or less
- Low cloud ceilings and active snowfall
- The presence of snowplows on the runway
- An airport status that was closed for maintenance/plowing
- A failure in communication where air traffic control personnel did not notify the pilot of unsafe conditions or the closed status of the airport
- Discrepancies in NOTAM information, as the controller was unaware of the specific closure and plowing activities