Narrative:

I was working the local position during the aftermath of a snowstorm. Maintenance plows requested permission to go onto runway 5 at taxiway C to 'do 180s' in order to clean the snow/snow ridges out of that intersection. I approved the request and advised of the next arrival; air carrier X; which at that point was 8 minutes from the airport. Air carrier X eventually checked in on the local control frequency at about an 8 mile final. I told air carrier X to continue; vehicles on the runway; expect landing clearance shortly. Air carrier X acknowledged this. I then told the plows to exit the runway; traffic 3 minutes out from the airport; report off the runway. They acknowledged this. About a minute later; the plows reported off the runway. I scanned the runway; observed no vehicles; and then cleared air carrier X to land; who at this point was on approximately a 3 mile final doing 120 kts. About 20 seconds later; I observed a snow blower enter the runway 5/taxiway C intersection without clearance from me. I immediately keyed up the frequency and asked 'who is the blower on runway 5?'. I observed the vehicle proceed to about the center line of the runway; make a 180; slowed just slightly; and after I asked my question; he proceeded quickly off the runway. I scanned the runway again; then advised air carrier X; who had heard this whole exchange taking place; that the runway was clear and that he was yet again cleared to land. Air carrier X advised that he had seen the whole situation as it occurred; and it wasn't a problem. I estimate that air carrier X was on a two mile final when this situation occurred; and if it had occurred 10 seconds later; an immediate go around would have had to been issued. We have asde-X at pvd; and the green bars were not displayed; which means the aircraft wasn't even inside a 1 mile final. Air carrier X landed without incident and taxied to the gate. No separation was lost since the vehicle did exit the runway prior to the aircraft crossing the threshold. Recommendation; since this was not an FAA issue; I don't know if there is anything the agency can do to prevent this from happening again. Mitigating factors could potentially include the fact that this was the first major snowstorm of the season (operator inexperience); and a 'changing of the guard' at the higher echelons of pvd airport on different theories on how snow removal should take place.

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Original NASA ASRS Text

Title: PVD controller described a near go around event when an airport snow removal vehicle entered the runway with traffic on final. Reporter cites first storm of the season and changes in airport management as possible causal factors.

Narrative: I was working the Local position during the aftermath of a snowstorm. Maintenance plows requested permission to go onto Runway 5 at Taxiway C to 'do 180s' in order to clean the snow/snow ridges out of that intersection. I approved the request and advised of the next arrival; Air Carrier X; which at that point was 8 minutes from the airport. Air Carrier X eventually checked in on the Local Control frequency at about an 8 mile final. I told Air Carrier X to continue; vehicles on the runway; expect landing clearance shortly. Air Carrier X acknowledged this. I then told the plows to exit the runway; traffic 3 minutes out from the airport; report off the runway. They acknowledged this. About a minute later; the plows reported off the runway. I scanned the runway; observed no vehicles; and then cleared Air Carrier X to land; who at this point was on approximately a 3 mile final doing 120 kts. About 20 seconds later; I observed a snow blower enter the Runway 5/Taxiway C intersection without clearance from me. I immediately keyed up the frequency and asked 'who is the blower on Runway 5?'. I observed the vehicle proceed to about the center line of the runway; make a 180; slowed just slightly; and after I asked my question; he proceeded quickly off the runway. I scanned the runway again; then advised Air Carrier X; who had heard this whole exchange taking place; that the runway was clear and that he was yet again cleared to land. Air Carrier X advised that he had seen the whole situation as it occurred; and it wasn't a problem. I estimate that Air Carrier X was on a two mile final when this situation occurred; and if it had occurred 10 seconds later; an immediate go around would have had to been issued. We have ASDE-X at PVD; and the green bars were not displayed; which means the aircraft wasn't even inside a 1 mile final. Air Carrier X landed without incident and taxied to the gate. No separation was lost since the vehicle did exit the runway prior to the aircraft crossing the threshold. Recommendation; since this was not an FAA issue; I don't know if there is anything the Agency can do to prevent this from happening again. Mitigating factors could potentially include the fact that this was the first major snowstorm of the season (operator inexperience); and a 'changing of the guard' at the higher echelons of PVD Airport on different theories on how snow removal should take place.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.