CEN21LA022

The pilot stated that the white airplane was on a taxiway and about 200 ft from the departure runway when it was struck from behind by an airport snowplow. The airplane sustained substantial damage. The pilot stated that before the taxi, he announced on the common traffic advisory frequency (CTAF) that he was departing the ramp and taxing to runway 13. After the collision, the snowplow driver asked the pilot if he made any position reports on the CTAF to which the pilot said no. Investigators were not able to resolve the discrepancy in the statements between the pilot and the snowplow driver. The snowplow driver stated that it was difficult to see the airplane due to a lack of contrast with the surrounding snow-covered terrain.

On October 18, 2020, about 1100 central daylight time, a Cessna 182Q, N97875, sustained substantial damaged when it was involved in an accident near Spearfish, South Dakota. The pilot and passenger were not injured. The airplane was operated as a Title 14 Code of Federal Regulations (CFR) Part 91 personal flight. The pilot stated that while preparing to depart Black Hills Airport-Clyde Ice Field (SPF), Spearfish, South Dakota, he witnessed a snowplow make several passes on the runway. The pilot reported that after de-icing the airplane and while positioned on the ramp, he contacted Ellsworth Approach Control on his cell phone for his clearance. The pilot saw the snowplow turn off the runway then made a radio call on the airport common traffic advisory frequency (CTAF), announcing that he was departing the ramp and taxing to runway 13. He stated that all the airplane lights were on as it moved from the ramp area. About 200 ft from the end of the taxiway, near the beginning of runway 13, the airplane was struck from behind by the snowplow. The pilot said he was not aware of what hit the airplane, until he exited the airplane. The airplane, which was primarily white in color, sustained substantial damage to the rudder and aft portion of the vertical stabilizer. A line service employee stated he did not hear the pilot make any radio calls on his taxi out. He told the pilot to watch for the snowplow that was plowing the runway. The line service employee said that he normally will call the snowplow driver to let him know of an airplane departing, but he did not do that before the accident because he assumed the snowplow driver saw the accident airplane while plowing the taxiway. The line service employee said the accident airplane was the first to depart the airport that day. The line service employee said he did not see the accident airplane taxi, but after the airplane engine started, it sat awhile on the ramp and had its lights on. The snowplow driver stated that he started work about 0900 or 1000 on the day of the accident. He said he asked the pilot if he made any position reports on CTAF, and the pilot said that he did not because he was communicating with Ellsworth Approach Control. The snowplow driver said airport personnel do not monitor Ellsworth Approach Control but monitor and communicate on CTAF. The snowplow driver said he always makes radio calls on CTAF when plowing on the runway and when exiting the runway. He does not make radio calls while on taxiways. He said it was difficult to see the airplane due to a lack of contrast with the surrounding snow-covered terrain. The SPF manager stated he was not working at the airport on the day of the accident. He said there was no surveillance video that would have captured the collision near the end or the runway. CTAF communications were not recorded at the airport. There was no Notices to Air Missions (NOTAMs) issued on the day of the accident and he said NOTAMs are issued when there issignificant snowfall. NOTAMS were not issued with snow accumulations of 1/2-1 inch of snow. Federal Aviation Administration (FAA) publication FAA Guide to Ground Vehicle Operations, Non-Towered Airports, stated: When the control tower is closed or if there is no tower, the airport is referred to as non-towered. At a non-towered airport, you do not need controller permission before entering a runway or taxiway. The document further lists some best practices for operating on a non-towered airport: When you approach the runways and taxiways, STOP, LOOK both ways, and LISTEN for aircraft that are landing or taking off. Vehicle windows should be open to do this properly. Alert others when you are using a taxiway or runway by always making an announcement on the radio before you enter. Be specific with your location and intentions. Always yield the right-of-way to taxiing aircraft and give them plenty of room. If an aircraft is headed toward you on the same taxiway, move out of the aircraft’s way. Always carry a radio tuned to the airport’s Common Traffic Advisory Frequency (CTAF) or UNICOM. If an aircraft is about to land on a runway that you need to cross, stop well clear of the runway. Continue to yield to the aircraft until it has landed and taxied off of the runway. Be aware that some aircraft at non-towered airports are not equipped with radios. Before you cross a runway, ensure that no potentially conflicting aircraft are taxiing, landing or taking off. Be aware of aircraft at non-towered airports that frequently make touch-and-go landings (immediately after landing, full power is applied and the aircraft takes off again). If your vehicle has a rotating beacon, be sure to turn it on anytime you are on the airport surface. Turn on headlights as well, being careful not to blind any pilots in the area.”