Sub stratum--back to the races.
So our January issue carried the story. The team, from Sussex County Technical High School in Sparta, N.J., designed and built an entry for the 9th International Submarine Races and placed first for innovation and third overall in the competition.
There were 26 entries in the competition. Most of them were designed and built by college undergraduates. The races are held every second year at the model basin at the Naval Surface Warfare Center's Carderock Division in Bethesda, Md. The basin is 22 feet deep and the course is 100 meters long.
Our article, "Pedaling Against the Tide," discussed the students' approaches to designing the submarine, and their use of engineering tools. For instance, they had used CFdesign CFD software from Blue Ridge Numerics and the Solid Edge CAD system from Siemens PLM Software. Computer analysis helped them optimize the propeller and the 16-foot-long hull.
We didn't say much about what was inside the hull or how the races were conducted.
After seeing the article and the photo we published, a reader wrote in expressing some reasonable concerns.
"I was alarmed at the lack of description of the safety items required for a submerged vehicle," the letter said. The reader had other questions, about air purification, freedom of motion, egress, and the propulsion system, and doubted that the submarine photographed being held aloft by the students was the one that had competed in the model basin.
We forwarded the reader's questions to Chris Land, a teacher at the school and the team's advisor. This is his reply:
"The sub that the kids and I are holding is the one and only Umptysquatch 3.2. The sub fills with water. The pilot breathes from standard scuba tanks with regulator. This alleviates the necessity for atmosphere control equipment. Egress is made possible from simple two-way latches on the escape hatch that can be operated from inside and outside the hull. In addition, a safety buoy system is installed to alert Navy divers if the pilot has become incapacitated. The divers will remove the pilot and bring him/her to the surface. Freedom of motion was the main design driver for a linear propulsion system. The relatively streamlined characteristics of this system allowed for the use of the efficient hydrodynamic shape of the hull.
"Safety of all participants in the International Submarine Races is the absolute ultimate priority of the event. It should be made clear that the safety specifications for all entrants are well defined in the participant manual. All aspects of the event are closely monitored by ISR personnel and the full complement of U.S. Navy divers that support the event."
The races are organized by the Foundation for Underwater Research and Education in Brunswick, Maine. Major sponsors of the event were the IEEE Oceanic Engineering Society and the Electric Boat Corp.
There is more information about the team's work, its key members, and Umptysquatch 3.2 available online. Control Products Inc. of East Hanover, N.J., which provided waterproof switches for the submarine, has published an article on its Web site, www.cpi-nj.com, that also provides a link to the final design report for the sub.
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|Title Annotation:||INPUT OUTPUT|
|Date:||Sep 1, 2008|
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