Stockholm-Arlanda Airport is well prepared for snow. The airport is one of the best in the world at snow removal. Air traffic may be delayed by heavy snowfall, but Arlanda never closes due to snow.
When heavy snow is expected, the Arlanda Snow Council/Tactical Forum gathers. This group includes representatives of snow removal staff, the airport’s Operations Department, the Air Navigation Service (ANS), the Swedish Meteorological and Hydrological Institute (SMHI), the airlines and ground handling companies. The affected parties are informed about the quantities of snow expected and the possible consequences. The Council decides what actions should be taken.
During the colder half of the year (roughly mid-October to mid-April), Stockholm-Arlanda has about 85 seasonally hired snow removal staff, or “snowmen”. Together with permanent staff, they form a team of 130 people who provide snow removal services. Special routes are planned for sweeping teams, which clear each runway at intervals of 35 to 45 minutes. The sweeping teams are directed via radio from the air traffic control tower.
Each team consists of eight PSB machines that move side by side. PSB stands for ploughing, sweeping and blowing. The PSB machines are followed by a snow thrower. As needed, a formiate truck comes last, spraying anti-skid agent on the runways.
It takes a sweeping team six to ten minutes to remove the snow on each runway.
When snow removal is completed on each runway, the surface is tested by a friction vehicle, which measures friction value. The airport announces the friction value, and then it is each pilot who decides whether this value is sufficient for a landing. The friction value determines how often a runway must be ploughed and treated with anti-skid agent.
Facts
Snow removal time for each runway:
Runway 1: 8 minutes
Runway 2: 6 minutes
Runway 3: 10 minutes
The fastest, most efficient way to keep two runways in operation during snowfall is to combine Runway 1 and Runway 2, since they are located close to each other.
The line of snow left behind by the PSB machines weighs 120 kilos per metre, so the airport uses one of the world’s largest snow throwers.
A two-centimetre snowfall means that 1,200 lorry loads must be carried to the airport’s snow dump.
The water that melts from the snow dump is gathered in ponds and is then transported in pipelines to a municipal water treatment plant.
The runway anti-skid agent used at Stockholm-Arlanda is called potassium formiate and consists of organic formic salts that decompose in a natural way.