Denmark For Martin Knudsen, a shiny red helicopter, weighing almost 3,000 kg, is his flying workplace and, in bad weather, he brings Vattenfall’s service technicians safely to the North Sea wind turbines for repairs.

On a sunny day with scattered clouds, the red helicopter lifts off smoothly from the small platform vehicle onto which 36-year-old helicopter pilot and flight instructor Martin Knudsen had landed it the day before. The loud noise from the rotors subsides as the door is closed and his headset ensures unhindered communications. Knudsen guides the helicopter slowly along the taxiway to the take-off pad, and with a steady movement of the control stick the cars on the ground are reduced to tiny beetles 1500 feet below.

When not in the air, Knudsen occupies a small office in UNI-FLY’s hangar at Esbjerg Airport. UNI-FLY is Vattenfall’s regular partner in the air and Knudsen is ready whenever air transport for Vattenfall’s service technicians is needed, or if an accident should occur out on the turbines and evacuation by air is required. The specially equipped helicopter, costing approximately DKK 40 million (EUR 5.38 million) and packing 800 hp in each of its two engines, can handle any situation on land or at sea.

“When I get into my seat, I feel like I’m part of the helicopter. I know exactly where I have it and how much power I can get out of it. In addition to the information from the instruments, the mechanical systems send out a host of signals that the pilot needs to pick up using all his senses,” says Knudsen with an intense glint in his eyes that leaves no doubt that he has a good measure of self-confidence.

A lot of instruments to pay attention to while flying the helicopter

Arctic experience
And Knudsen has good reason to be self-confident, due to 13 years of experience behind the many digital monitors, controls and handles. He has taken part in two expeditions as a pilot for Royal Arctic Line, which, among other things, supplies provisions to small communities on the east coast of Greenland. They are icebound for most of the year, but the ice begins to break up in late June, so it was Knudsen’s job, together with the ship’s captain or second officer, to find a route from the helicopter through the ice for the 110-metre-long supply ship.

“Seafaring and flying have many things in common, such as navigation. We also use units such as nautical miles and knots and, in Greenland, both ships and helicopters navigate by taking bearings using old maritime and land maps, landfall markers and radar. As so few people use GPS there, it is not as highly developed: sometimes it showed us that we were on land while, in reality, we were a good bit out at sea.”

The trips to Greenland meant lots of experiences and exciting tasks for Knudsen. Up there you have to be creative, improvise and help each other as much as possible, because the long distances make things difficult. In northern Greenland, he once had to pick up an elderly man with heart problems from a cruise ship that was unable to enter the harbour because of ice. The ship had no landing platform, so the patient was taken by a smaller boat to a large ice floe, onto which Martin carefully landed the helicopter so that the ship’s doctor and the stretcher with the patient could be taken aboard. This was far from being a standard procedure, but everything went well, and the patient quickly reached land and received treatment.

This is how Vattenfall’s service technicians get to work, when the weather is bad. Take a couple of minutes to get the feeling of a helicopter ride to the Horns Rev 1 offshore wind farm in the North Sea.

A private concert in the cabin
As well as flights in Greenland for Royal Arctic Line, the Danish Sirius patrol, geologists and others, at home in Denmark, Knudsen has carried out photo-reconnaissance flights, cable inspections for Danish utility companies, transported heavy spare parts suspended under the helicopter and flown VIPs such as Danish singers Medina and Mads Langer. He particularly remembers one trip where he enjoyed a private concert with song recitals and vocal warmup from the international Danish opera singer Stig Rossen, who was on his way between two concerts in Denmark. But since 2008, he has been back in Esbjerg and has flown regularly to offshore wind turbines and -installations.

Through stormy weather
Vattenfall’s service technicians mainly use boats as a means of transport when they need to go out to the wind turbines at Horns Rev 1 in the North Sea for maintenance and repair tasks. But if the waves reach higher than about 1.2 metres, or there is ice on the water, the helicopter is called into action. Therefore, the winter months with heavy winds and high waves are the busiest season for the helicopter.

“Naturally, it’s more expensive to fly, as we can only carry four service technicians at a time. But Vattenfall’s Surveillance Centre in Esbjerg determines the costs of whether having turbines stand still is more expensive than sending out a team with the helicopter,” Knudsen explains.

When the helicopter brings service technicians out to the wind turbines, they are lowered onto a platform on the turbine with the aid of a steel cable and a crane mounted on the helicopter. The technical term is to “hoist” the service technicians, the concept of which – used on wind turbines – was developed by UNI-FLY. Otherwise, a helicopter hoist was mainly used to lift people up during rescue missions.

UNI-FLY has carried out more than 30,000 hoist operations so far, and Knudsen, who was involved in developing the technique, has now, after 13 years at UNI-FLY, personally flown several thousand hoisting operations.

Blade specialist Rikke Balle on her way to Horns Rev 1

“Parking” on an A4 sheet of paper
“It’s important for us that the transport to and from the workplace is as safe and comfortable as possible. We take no unnecessary risks – after all, generating electricity is not a matter of life and death, as might otherwise be the case during a rescue mission. All of the service technicians who take part in the hoist operations have taken a training course with us, so they are suitably prepared for the operation. I myself am an instructor for the course,” Knudsen explains.

When asked whether it is dangerous, Knudsen replies that he would not do it if it was not 100 per cent safe.

“We can certainly fly in really bad weather, in and above the clouds, but when I ‘park’ the helicopter above a turbine, we must always have full visibility down to the turbine. Vattenfall’s Surveillance Centre can remotely control all the wind turbines from land and they stop the turbine in question before we begin hoisting the technician.”

Knudsen explains that during the hoist operation, he can maintain the helicopter’s movement within an area corresponding to a sheet of A4 paper. It has taken many hours of training to build up the close cooperation between the pilot and the other crew member – who, as well as being hoist operator, is the helicopter’s mechanic. Both use completely standardised terminology when they are close to the turbines so that no misunderstandings arise.

“We can fly in strong winds, but there’s not the same turbulence over water as over land, and that makes it easier to precisely control the helicopter. The helicopter is fully equipped with an autopilot and stabilisation systems that we use when flying to and from the wind farm. But during the hoist operations on the wind turbines, I completely control the helicopter manually – the automatic systems are not adequate to control hovering above the turbine. A combination of good reference points on the turbine and close cooperation with the hoist operator ensures that we can hoist the technicians in an incredibly precise and safe way.”

Service technician on top of a Horns Rev 1 wind turbine

Rescue standby
In addition to the regular flying assignments with Vattenfall’s service technicians, UNI-FLY acts as a rescue standby service if someone is injured on one of Vattenfall’s offshore wind turbines.

“I once picked up a man from a platform because there was concern that he had suffered an embolism. The helicopter can be set up in a jiffy so that there’s room for a stretcher, and we can be in the air within a few minutes. On a rescue mission, we take along a complete rescue kit with a stretcher, defibrillator, medical equipment and many other items so that we can handle any conceivable situation.”

In the event of an accident, UNI-FLY works together with Falck, which contributes with an ambulance paramedic. Their personnel are also trained to be hoisted down onto the wind turbine and ensure professional on-site aid, as every minute can be critical. The helicopter can then bring the injured person quickly back ashore.

Professional cooperation
Knudsen really enjoys his work in the little cabin and his daily experiences in the air. The same applies to his cooperation with his colleagues from Vattenfall both on board the helicopter and in contact with the Surveillance Centre in Esbjerg.

“They are all professionals and are used to working with safety procedures. That makes life easier for the helicopter crew and means we can solve almost any task together,” Knudsen adds before checking the weather and the helicopter together with his hoist operator, so that everything is ready for their next mission in the air above Esbjerg.

Related content