Midshipmen in the United States Naval Academy’s engineering department recently tested their semester-ending project in the academy’s 380-foot tow tank.
And, more than just a passing grade in the class was at stake: The team would present the results two weeks later to members of Boeing Phantom Works.
“They came up with some very unique approaches,” said Boeing project manager, Keith Coleman. “Some of which have never been tried before. Two line, single line, submersible type approaches. It was a very innovative approach all around.”
Several months ago, Phantom Works challenged the team to find a new way to retrieve an unmanned aerial vehicle while at sea, but without requiring large amounts of deck space on any given ship.
The Naval Academy students created a retrieval process very similar to the Scan Eagle’s single line skyhook retrieval system. Their system hangs over the side of the ship and drags the retrieval line in the water. At the end of the retrieval line is an underwater hydrofoil prototype the students created. The midshipmen’s concept drags the underwater vehicle at end of the retrieval line in order to divert the energy from the impact (when a unmanned aerial vehicle hits the line) to the craft beneath the water’s surface. The hydrofoil absorbs most of that energy in order to create less stress on the fast-moving UAV.
After two days of testing that included more than ten different impacts, the midshipmen saw their concept successfully come to life. Senior Jeff Matcham explained how the prototype behaved exactly how their calculations expected.
“When we impacted it with all the weight,” Matcham said, “it did what we needed it to do, which was dive down. We want it to dive. We don’t want it coming out of the water. We don’t want to have it get sucked up. It needs to dive down, and it did, which was huge.”