As President Donald Trump continues to insist that the US needs to own Greenland, his wider focus on the Arctic region has seen Washington order new icebreakers.
For these ships, which can sail through seas covered in solid ice, the US has gone to the world expert – Finland.
Temperatures are sub-zero inside Aker Arctic Technology's ice laboratory, as the scale model of an icebreaker cruises down a 70m-long simulation tank.
It ploughs a neat channel through the frozen surface of the water.
Undergoing testing at a facility in Helsinki, Finland's capital, this is a design for the next generation of the country's icebreakers.
"It's crucial that it has sufficient structural strength and engine power," says ice performance engineer, Riikka Matala.
Mika Hovilainen, the firm's chief executive, adds that the shape of the vessel is also crucial. "You have to have a hull form that breaks ice by bending it downwards," he says. "It's not cutting, it's not slicing."



