How does your airport prepare for the winter season? Can you describe the planning process and timeline?
Pyry Pennanen: Off-season we do a lot of preparation for the winter. For example, we go through and service all our winter equipment at our own garage at the airport. We check our snow removal procedures usually twice a year, during springtime after the winter season and autumntime before the next winter season begins. There can be some changes in the airport layout that require us to modify our procedures, or we make some small adjustments in the maps or timetables we have. We also employ a lot of seasonal employees for the winter and start their recruitment well in advance during the summer.
What specific strategies or technologies do you use to predict and manage winter weather conditions?
Aviation weather services play a key role when planning airport operations such as runway and apron maintenance or de-icing. We work closely with the Finnish Meteorological Institute, and they have an aviation weather observation system at every airport in Finland. Finavia shares information about the weather conditions with companies operating at its airports so that each organisation can take the effects of the weather into account in its own operations. With high-quality weather information, we can predict the impact of the weather on airport operations. By doing this, we can reduce the impact of weather, such as delays in air traffic.
What are the key components of your snow and ice removal plan? How do you prioritise areas such as runways, taxiways and aprons?
The runways are our number one priority, so we always begin with them. We have pre-planned snow clearance maps for each runway combination usage we have, so those define the order in which we take care of them and the main taxiways. Secondly, we start ploughing and sweeping snow from our apron taxiways, aircraft stands and service roads.
What types of equipment and de-icing chemicals do you use for snow and ice removal? How do you ensure they are effective and environmentally safe?
To put the scale of our operations into a perspective, at Helsinki Airport we have a 13-minute window, coordinated with the air traffic control, to clear a 3,500m-long and 60m-wide runway in one go. For this to succeed, we need very large and powerful machinery. Helsinki Airport’s winter fleet consists of approximately 200 vehicles and machines, and 135 maintenance employees trained in ‘snow-how’. Clearing one runway of snow takes approximately 11 minutes.
13 minutes
How long the team at Helsinki Airport have to clear a 3,500m-long and 60m-wide runway in one go.
For equipment, we have in total 21 sweepers, six snow blowers, six chemical sprayers, four friction measurement vehicles, ten-wheel loaders and several trucks, tractors, aggregate blowers and other smaller but still very useful machines. We most commonly use mechanical runway anti-skid methods, such as sweeping and ploughing. However, anti-skid agents are also required for removing frost and ice from the runway surface and for skid prevention. For anti-skid agents we use acetates and formates that are not classified as hazardous, but they cause environmental load on bodies of water.
To mitigate the effects the anti-icing agents may have on nearby waters, Finavia monitors the quality of groundwater and surface waters at Helsinki Airport. The monitoring is carried out both on a voluntary basis and in compliance with environmental permit conditions or as agreed with the environmental authorities. Water acidity, chemical oxygen consumption, electrical conductivity and oxygen content are determined from samples taken from wells, groundwater pipelines, runoff drainage and water bodies in the vicinity of airports. During weather events we also increasingly focus on the number of de-icing agents we use to de-ice the runways and aprons to ensure that we use the right amount to ensure safe operations but not too much.
How do you train your staff to handle winter operations? Are there specific training programmes or certifications required?
We employ a lot of seasonal employees each season and for those who start their first season with us, we give out a special two-week-long intensive learning course. This includes ground traffic instructions for the drivers permit, getting to know the sweepers and other machinery, learning the area and safety education to name a few topics. After two weeks we start training them to become a member of the snow team and we find a suitable role for each of them.
How do you manage staffing during severe weather events to ensure adequate coverage and safety?
We must make sure we have enough staff per shift, both our own personnel and our contractors, so every key role is filled. We do routine checks on our equipment to make sure they are ready for action. We do case-bycase preparations in close cooperation with air traffic control. Before we start, we make sure everybody understands their own role in the team and understands the objective.
How do you coordinate with airlines, air traffic control and ground services during winter weather events?
When the Finnish Meteorological Institute notices a challenging winter weather front closing in, we host a weather meeting for all airport stakeholders to join and get an update for the next 24 to 48 hours. We want to make sure that all parties acting on the apron and airfield understand what’s coming and can, and will, have the time to adjust their resources.
To keep an airport operational in the winter requires seamless cooperation within the whole airport community. What is particularly important is continuous dialogue between air traffic control and airport maintenance as well as apron management, ground handling companies and airlines.
What communication strategies do you use to keep passengers informed about delays, cancellations, and safety procedures?
Our communications team works closely with the operational side. When we know a challenging snow event is coming, they join weather meetings and are kept up to date on the situation. Depending on the severity of the event, we communicate to passengers on our website and social media channels to best prepare airport visitors for the unusual circumstances. We also communicate about the situation and any possible flight delays/cancellations at the airport via announcements and flight display systems. Our communications team also works closely with local media during events to further communicate the situation to a wider audience.
What measures do you take to ensure the safety of passengers and staff during winter operations?
We always aim to keep our runways operational and to ensure smooth travel at Helsinki Airport, but if the weather is simply too challenging, we temporarily close a runway and maintain just one for operation. Flight safety is always our number one priority and we never compromise on it.
During snowfall and especially afterwards we have a process called target snow removal (TSR). TSR allows us to create empty gate areas from aircraft and GSE via stand planning. We create an empty stretch of five to six gate stands and clear all the snow at one time. This creates a more safe and suitable working conditions for ground handlers and other ground staff.
What are the biggest challenges your airport faces during the winter season, and how do you address them?
On a typical year, Helsinki Airport is hit one to three times by such challenging weather conditions that it has significant effects on air traffic. One of the most challenging elements is supercooled water. When supercooled water rains on a runway or on the surface of an airplane, it freezes immediately. During winter, we must also consider wind direction and the amount of supercooled rain to adjust anti-icing agents in correct amounts. Another challenging situation is when a blizzard is accompanied by damp freezing weather. That’s when aircraft engines freeze, and airlines must de-ice the fan blades before taking off, which can cause further delays.
Global air traffic schedules also play a big role, which affect the punctuality of airline flights. If, for example, a flight arriving from Spain to Helsinki Airport is delayed, it also affects the departure time of the return flight. Then, when the return flight is ready to depart, the flight may be delayed because it must apply for a new departure and entry permit from Eurocontrol. The wait can take up to several hours.
How do you evaluate the effectiveness of your winter operations? Are there specific metrics or performance indicators you monitor?
It’s a combination of different factors such as runway operations per hour and how many runways are we able to maintain operational during a snow event. One thing we’ve really focused on in the last couple of seasons is the number of de-icing agents we use to de-ice the runways and aprons. We want to make sure that we have the information available to make the right decision on the amount of liquids and solids to use. You want to use enough but not too much and sometimes nothing at all.
Can you provide examples of past winter events where your operations were particularly successful or where you learned valuable lessons?
We had a particularly challenging snow event this April, meaning that we had already switched to summer operations. Our seasonal employees had left for the time being, we had fitted summer tires on our equipment, returned our seasonal rental equipment and the amount of snow was one of the most we had for the entire season. With great cooperation and hard work, we managed to keep the runways open and in safe condition. It was a challenging situation and took a lot of pre-planning.
How do you mitigate the environmental impact of winter operations, particularly regarding the use of de-icing chemicals and fuel consumption?
Helsinki Airport, like all our 20 airports around Finland, has been carbon neutral since 2019. Next year, all our airports will reach the level of net-zero carbon emission. One of the ways we’ve achieved this is by using renewable fuel for our airport vehicles; for example, diesel made from waste and residues. Approximately one third of carbon dioxide emissions at our airports come from vehicles used in airport maintenance. We seek to achieve zero emissions in maintenance operations by increasing the use of renewable fuels and by continuously improving the efficiency of maintenance operations. We are continuously monitoring the development of fleet technology and looking for opportunities to apply new solutions in an airport environment.
Water management is also a significant part of our environmental work: we continuously monitor the quality of groundwater and surface waters at Helsinki Airport and develop the management of de-icing agents. We’ve built two remote de-icing areas at the airport where almost all the de-icing takes place. With the help of vacuum vehicles and separate drains, we can collect the fluid from the apron, which then ends up being put to use at a wastewater treatment plant.
Last winter, we also started using recycled propylene glycol as de-icing fluid for the first time at Helsinki Airport. Recycled de-icing fluid is manufactured to be identical to new de-icing fluid and it is a more environmentally friendly alternative.
In 2023 we introduced a subsurface wetland that will improve the conditions of fish and microorganisms in nearby streams and ditches by reducing the load on bodies of water and the erosion of streambeds caused by aircraft de-icing and runway anti-skid agents. Runway and apron stormwater is diverted to the wetland that filters water through gravel and the biofilm that grows on the gravel. Compressed air pumped to the bottom of the wetland increases the efficiency of microbial decomposition. The project is the first of its kind in the Nordic countries.
