UCSD Human Powered Submarine Takes The Plunge

UCSD ASME students took the plunge with their Human Powered Submarine, “Legasea”, at the 12th International Submarine Races in Bethesda, MD, this past June.

The event was held at the Carderock Division of the Naval Surface Warfare Center in the David Taylor Model Basin, one of the largest ship model basins in the world. The competition consisted of 19 teams competing in a 100 meter race. Each team was required to design and build a one or two-person “Wet” submarine, which has a completely flooded hull and requires the crew members to breath SCUBA from an onboard air supply.

Screen Shot 2013-11-27 at 3.18.28 PM

UCSD students designed and created “Legasea”, a 2-man, propellor-driven, Human Powered Submarine that was designed with SolidWorks and built from scratch by UCSD students. Students relied almost entirely on donations, both material and financial, to bring Legasea to life.

Screen Shot 2013-11-15 at 4.34.55 PM

Coastal Enterprises was proud to donate Precision Board to the UCSD Human Powered Submarine team to use for their mold-making process for the submarine’s body.

Screen Shot 2013-11-27 at 3.30.57 PM

According to Elliot LaBarge, team leader, “We planned to use the 10lb and 15lb. Precision Board we had to make molds we could pull the fiberglass body components of the submarine from. Since the submarine is 21′ long, we decided to make three separate molds and join them together – a task we learned was much easier said than done, due to the large size of the molds.”

Diversified Manufacturing of California was kind enough to lend their CNC capabilities and expertise to the students, producing three perfect molds from Precision Board PBLT-10 and PBLT-15 and spraying them with PLC Polyprimer 903 Black. Once the molds were back in the students hands, they coated them with a Honey Wax mold release compound and PVA (polyvinyl alcohol), and were able to successfully pull three separate body components – a fiberglass nose, center and tail.

Once the body components were ready, the battle wasn’t over yet. An extensive assembly process began followed by as much testing as possible before the race.

“Precision Board worked great because not only is it durable and able to withstand several pulls, but it also has excellent machinability, which really helped us bring the submarine we designed to life”, says Elliott.


When it came time to race in June earlier this year, Legasea placed 3rd in the two-person, propellor-driven category. Sub speed was measured by two timing gates halfway through the course, which recorded Legasea’s top speed at 3.42 knots. Unfortunately, a critical failure of the steering control rods rendered them inoperable, resulting in Legasea being unable to complete the final race.


The next International Submarine Races will be held in June of 2015, and Coastal Enterprises will be working closely with the new team leader, Mr. Alistair Twombly, as they redesign Legasea for the next competition.

Check out more info about this project on the official UCSD Human Powered Submarine website: http://asme.ucsd.edu.

Video of the final “pool test” prior to the race: