Investigation Summary
The accident occurred during a period of poor visibility and active snow removal operations. The flight crew had been briefed on blowing snow via ATIS but were never informed by air traffic control that vehicles were currently operating on Runway 3. As Flight 650 approached, the tower controller cleared the aircraft to land without coordinating with the snow removal crew or instructing the sweeper to exit the runway. The pilots, seeing snow blowing across the runway, assumed it was natural weather rather than the wake of a vehicle. Upon touchdown and deployment of spoilers, the aircraft entered a dense cloud of snow kicked up by Sweeper 7. The right wing struck the vehicle, resulting in a massive fuel leak and a brief fireball. The NTSB investigation highlighted a breakdown in communication and supervision within the control tower, noting that no contact was made with the sweeper driver after the flight was cleared for approach.
Final Conclusions
The National Transportation Safety Board (NTSB) determined the probable cause was inadequate control tower service by air traffic control personnel. Contributing factors included poor weather conditions (snow, obscuration, and low ceiling) and the presence of ground vehicles on the active runway. The investigation concluded that the snow removal operations were inadequately supervised, as the tower failed to ensure the runway was clear and failed to coordinate the exit of the authorized sweeper before granting landing clearance to Flight 650.
Video Analysis
No video analysis linked for this case file yet.
Airframe & Maintenance
Systems & Failure Modes
Air Traffic Control (ATC) Coordination
The tower was responsible for coordinating between arriving aircraft and ground vehicles; a failure to communicate with the snow sweeper led to the runway incursion.
Automatic Terminal Information Service (ATIS)
The broadcast system provided weather data that, while accurate regarding blowing snow, lacked specific warnings about ground equipment on the runway.
Interesting Facts
- 01The snow plow driver, Douglas Stoner, was the sole fatality of the accident.
- 02The aircraft's right wing was completely torn off during the collision.
- 03The ATIS report mentioned blowing snow, which led the pilots to believe the snow they saw on the runway was weather-related.
- 04The tower controller failed to advise the flight crew of active snow removal operations on the runway.
- 05The aircraft spun 180 degrees and came to rest to the left of the runway centerline.
Safety Actions & Advisories
ATC Supervision Improvements
The NTSB recommended stricter supervision of snow removal operations and improved coordination protocols between tower controllers and ground vehicle operators.