Controlling a single-track hydrofoil is like controlling a bicycle, two Masters student from Delft University claim in a paper published in Naval Engineers Journal last month.
“We used a mathematical model to validate whether a single-track hydrofoil using two foils, one behind the other in the water, would remain stable in the same way as we stay upright on a bike,” one of the students, Gijsbert van Marrewijk, told Delft University last week. The principle of staying upright on a bike is the one of steering into the fall.
Van Marrewijk and his co-author Johan Schonebaum were inspired by the hydrofoil boat of the Solar Boat team of their university, of which they were members. Hydrofoil boats have wings under the hull that lift the boat out of the water, reducing drag and, all other things being equal, increasing speed. Using a single-track hydrofoil reduces drag even further over the more conventional and more stable multi-track vehicle.
See the 2015 version of the Delft University Solar Boat team in action:
For some reason recent versions of the boat have returned to multi-track hydrofoils. The mathematical model developed by the two students should make it easier to test new designs in a computer simulation.
Photo by Wikimedia Commons user Gbvm2, some rights reserved.
Castelein, 1:53 into the video: 
Last Friday a diver of the Schoonhoven fire department saved millions of Dutch people a few jittery hours when he put his foot against the wall of a ship carrying coffee to stop water from flowing in.
The recently restored former passenger liner SS Rotterdam will stay in the city it was named after, 
