One submarine at the surface and one underwater. (Image courtesy of European International Submarine Races.)
This summer will see engineering student teams from universities across the US, Canada and Europe participating in a unique sporting and engineering challenge: the biennial European International Submarine Race (eISR).
The competition involves the design, building and racing of a flooded submarine vehicle powered and piloted by one or two people in scuba gear.
Like many engineering competitions, the eISR aims to help engineering students develop practical engineering skills, strong teamwork capabilities in a time-critical environment and the ability to find and implement solutions with limited facilities or resources.
Propulsion power for the submarine must be provided solely by the pilot during the course of the race, meaning designs cannot include energy storage devices such as batteries or flywheels.
A cutaway depiction of David Bushnell's Turtle.
A watertight hull is not required in the submarine’s design. This will help ensure that the designs focus on innovative engineering of the hull and propulsion method, rather than waterproofing techniques. This also means that all pilots must be certified divers with scuba gear.
Though this competition focuses on innovative engineering, the idea of a human-powered submarine is not a new one. The first single-pilot, human-powered submersible is known as David Bushnell’s Turtle, designed and built in 1775 as a military machine meant to attach explosives to the underside of British warships in New York Harbour.
Submarine Design
A submarine is defined in the competition rulebook as, “a flooded underwater vehicle which fully encloses a pilot and all of the control and propulsion mechanisms. It must operate entirely beneath the surface of the water and be propelled by a fluid-coupled device, such as propellers, jets or wings.”
The competition’s design process is broken down into five main components:
- Hull design
- Propulsion system
- Transmission system
- Pilot safety and ergonomics
- Control system
Hull design and manufacture in particular is a determining step for most teams. This step will require research into appropriate designs, after which teams will create a CAD model and then proceed to the actual build. After that, teams will design the propulsion and other systems and install or attach all the additional parts to the hull.
The design aspect of the competition will be evaluated through the submission of two report documents and a presentation on the engineering and design of the sub.
Regardless of the propulsion system a team designs, there are some general specifications that must be followed for all submarines in the competition:
- Maximum dimensions of 5.5m in length and 1.5m wide
- The center of gravity when out of the water (dry or draining) must be between 2.1m and 3.1m from the bow or stern extremity
- It must be crewed by one or two pilots with diving certification and full scuba gear
- It must have a water-couple propulsion with a screw propeller or other propulsion system that is directly coupled to and powered by the pilot or pilots, who will be fully encapsulated within the hull
- Hydraulic, pneumatic and electric transmission systems are permitted only so long as all the energy used in the propulsion is produced by the pilot in real time
- Wheels or other mechanisms that generate movement through friction against the bottom or walls, or power sources such as flywheels and batteries are not permitted.
The full list of specifications is available in the 2016 eISR Rulebook.
The Racecourse
One unique aspect of the eISR race is that unlike other submarine competition races that use a timed straight-line speed course, the eISR has introduced a slalom course.
Races will still take place one submarine at a time in a timed race-the-clock format, but will incorporate an out-and-back race structure with slalom gates set up along the return leg of the race. The total length of the race course is approximately 175m, though the actual distances traveled may vary depending on how tight a given submarine manages to take the 180-degree turn at the halfway point.
Timing gates are set up 42 m into the first leg, with the midpoint turn on a 25m radius set between gates. A set of four slalom poles are set on the return leg and serve to showcase a sub’s maneuverability as well as slow the vehicle down on approach to the finish line area.
What Can Teams Win?
The competition offers awards for several aspects of design and manufacture as well as race performance.
Grand Prize – eISR Trophy and All-Round Runner Up
The overall winner will be determined according to combined design, manufacture, race performance and reliability factors.
Week’s Top Speed
This award will go to the team with the fastest transit of the timing gates during the week of competition. The submarine must complete the run in order for the speed to qualify.
Agility Award
Teams who qualify during the race heats will have the opportunity to run a double-length course, twice through the timing gates and slalom course, to provide an agility challenge.
Award for Innovation
This prize will be given to the team whom the judges deem to have presented the greatest engineering innovation in its design.
Best Presentation
This award will be given to the team that offers the best presentation of its submarine design, both visually and verbally.
Where and When
The 2016 competition takes place from July 6-15th at the QinetiQ Ocean Basin testing facility at Haslar, Gosport, England. The first day is a dry day for final preparations, dry judging of the submarine designs and diver checkouts. The following two days will be dedicated to ballast and wet inspections.
The race is structured into heats, one in the morning and one in the afternoon, with six submarines in each heat. At the end of the week, the panel of judges will present the awards to winning teams.
To follow the progress of these submarine races, check out the European International Submarine Races website.