Robotic underwater glider sets out to circumnavigate the globe

Redwing, a robotic submarine about the size of a surfboard, is embarking on a five-year journey that will follow the famed explorer Ferdinand Magellan's voyage around the world A small robot submarine is setting out to go around the world for the first time. Teledyne Marine and Rutgers University New Brunswick in New Jersey are launching an underwater glider called Redwing on its Sentinel Mission from Martha's Vineyard in Massachusetts on 11 October. Researchers have been using underwater gliders since the 1990s. Rather than a propeller, gliders have a buoyancy engine, a gas-filled piston that slightly changes the craft's overall buoyancy. An electric motor pushes the piston in to make the glider heavier than water so it slowly sinks, coasting downwards at a shallow angle.