Supercavitation is the use of cavitation effects to create a bubble of gas inside a liquid large enough to encompass an object travelling through the liquid, greatly reducing the skin friction drag on the object and enabling achievement of very high speeds. Current applications are mainly limited to projectiles or very fast torpedoes, and some propellers, but in principle the technique could be extended to include entire vehicles.
In a world of rapidly evolving threats, every branch of the military is looking for a way to respond as quickly as possible. But whereas the Air Force, Army and Marines can simply fly to whatever hot spot flares up next, the Navy, by its very nature, still needs to sail. That’s where the Underwater Express comes in.
Currently, the Navy’s fastest submarine can only travel at 25 to 30 knots while submerged. But if everything goes according to plan, the Underwater Express will speed along at 100 knots, allowing the delivery of men and materiel faster than ever.
The DARPA program, first announced in 2006, has finally reached the testing phase. Electric Boat, the company contracted to design the Underwater Express, is producing a quarter-scale model of the speedy sub, to be tested next year off the coast of Rhode Island.
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