The Human-Powered Submarine Team (HPS), an ocean engineering club at Florida Atlantic University, competed in the bi-annual European International Submarine Races (EISR) in Gosport, England from June 22 to July 6.

HPS, composed of seven aspiring young FAU engineers, faced off against 11 university teams from around the world in a multi-day event that tested the speed and maneuverability of their submarines. The team shared their story about returning home with a second-place trophy overall and for second-highest top speed.

In addition, the EISR judges awarded the team with the “Reliability” award for completing the course more times than any other team and having the fewest aborts, as well as the “Communication” award for effective social media outreach.

“We’re focusing on speed,” said Emily Serrano, the club’s marketing director who graduated in May 2024 with a bachelor’s degree in bio-anthropology and neuroscience. She said HPS competed in the International Submarine Races last year in Maryland, which is held in a temperature-controlled environment.

The HPS team originated in 1989 and has focused on designing and racing cutting-edge submarines that rely solely on human power to propel their vessels — competing regularly, winning several prizes and setting speed records.

A human-powered submarine relies entirely on the pilot’s physical effort, and no onboard energy storage systems can be pre-charged before crossing the starting line, according to Twain Glas, the club’s president. 

“You can have energy storage in the submarine, as long as it’s all produced and expelled during the race by a human,” said Glas. “For example, someone pedaling could generate energy that goes into a battery, which then powers the propellers, but that battery cannot be charged before crossing the starting line, and all the energy must be used up before crossing the finish line.”

Unlike pressure vessels that have a supply of oxygen for drivers, these race submarine operators rely on SCUBA gear for breathing. Additionally, the team says they manage free-flooding, address weight issues, achieve proper buoyancy and develop innovative propulsion systems. During the race, one pilot sits inside while six support divers accompany the vessel in the water.

Typically, a human-powered submarine consists of a main hull made out of fiberglass, control surfaces and intricate internal mechanical systems, all manually operated by a pedaling pilot, according to Glas. Students design and build these systems from scratch, with support from technical staff and faculty in FAU’s Ocean and Mechanical Engineering Department.

The team’s submarine this year, “Owlbacore,” is named after the USS Albacore – an experimental Navy submarine known for its speed – and features contra-rotating propellers to prevent the vessel from rolling.

“Our hull design and steering mechanisms are based on those used in the USS Albacore,” said Glas. 

Glas, who recently graduated from FAU with a master’s in ocean engineering, has been part of the club for three years. Under his leadership, the team adopted a “back to basics” approach, replacing electronic steering with mechanical steering due to issues encountered with the electronic system in their previous submarine, Atlantic III.

Despite the races taking place in basins about 15 feet deep, he said the team opted to conduct ocean tests with Owlbacore six times, reaching depths of approximately 20 feet.

“[The ocean] was the most accessible place to test because lots of the places that are pools, they aren’t deep enough or long enough,” Serrano said. “In the ocean, we can go as far as we want, and we don’t need to ask for permission.”

These tests presented the team with both opportunities and challenges, including low visibility and evacuations due to approaching thunderstorms and strong currents.

“We have to be way more coordinated, especially with things like current. That’s been the biggest issue recently,” Glas said. “Yesterday, the current was ripping, and it was dragging us across the bottom even though we have tons of weight in our pockets. But …we had tons of practice in a harsher environment [than the basin], so it has really prepped us for this race.”

Glas and Serrano reported that the team worked a minimum of seven hours daily leading up to the EISR.

They stated that the EISR requires teams to meet certain requirements and undergo testing procedures. One critical aspect of their preparation is the wet test, or wet check, where the team must demonstrate their submarine’s ability to move both forward and backward. They also need to prove that the dead man buoy system works and that the pilot can enter and exit the submarine independently.

Robert Mascia, the team’s pilot, joined HPS through his involvement in FAU’s SCUBA and Snorkel club. 

“It’s very tiring… I have to focus on pedaling, steering left and right and keeping [the submarine] off the ground or from hitting the surface of the water,” said Mascia.

The EISR race took place at a depth of six meters in QinetiQ’s Ocean Basin facility at Haslar, Europe’s largest freshwater tank. The 200-meter EISR racecourse starts with a sprint through two gates, followed by a 180° turn and a slalom that becomes increasingly challenging as the competition advances. Penalties are given for missing, hitting, or dragging marker poles — as well as for breaching the water’s surface.

Mascia piloted in two consecutive competitions and describes the course as “a big U-turn and a slalom,” and continued saying the course becomes more challenging each day of the competition, with the slalom sections progressively tightening. HPS’ best time was 1 minute and 43 seconds, with a top speed of 4.53 nautical miles, while the winning team reached 5.29 nautical miles, according to Mascia.

Pilots are fully submerged and face downward. They paddle as fast as possible with bike shoes for better grip on the pedals, directly powering the submarine with their energy. The submarines are designed for safety, allowing pilots to quickly get in and out if necessary, and they always carry two air tanks during races.

To qualify for the races, the team submitted videos showing the steering system in action, the submarine’s ability to move forward and make turns and the functionality of the dead man buoy. Serrano is responsible for taking footage of the submarine underwater using a Go-Pro camera.

Additionally, the competition rules stipulate that a submarine can only be used a maximum of twice per race as long as there are major modifications to the hull, ensuring that teams cannot compete with the same submarine repeatedly – according to the EISR rulebook.

“You have to prove that the engineers are capable of building the hull,” said Glas.

The race allows for both one-man and two-man submarines, but they must adhere to specific length and width requirements.

“All the teams are looking to make the submarine as small as possible because that makes for a faster submarine,” said Glas. “Our predecessor, Atlantic III, was the smallest submarine FAU has ever made. It was so tight that our pilot could only take about three-quarters of a full breath of air.”

Glas explained Owlbacore is a bit bigger, with a maximum cross-section of 23.5 inches compared to Atlantic III’s 22 inches. It was also the largest submarine in the race.

“[Atlantic III] was too tight for me to fit in,” said Mascia. “My knees would scrape on the bottom. But this last sub was made to my size.”

The team was able to transport Owlbacore using a specialized crate custom-built by Craters and Freighters, which also held their dive gear and tools.

The team is getting ready to compete at the Subracing Series competition on September 21 in Playa de Arinaga, a small coastal town in the Canary Islands, where they will also compete with Owlbacore. 

Laurie Mermet is the Student Life Editor for the University Press. For information regarding this or other stories, email [email protected] or DM laurie.mmt on Instagram.