Supercavitation

Supercavitation is the use of a cavitation bubble to reduce skin friction drag on a submerged object and enable high speeds.

Applications include torpedoes and propellers, but in theory, the technique could be extended to an entire underwater vessel.

A key feature of the supercavitating object is the nose, which typically has a sharp edge around its perimeter to form the cavitation bubble.

[6] The projectile's terminal ballistic design enables the explosive destruction of sea mines as deep as 45 meters (148 ft) with a single round.

[7] In 2000 at Aberdeen Proving Ground, RAMICS projectiles fired from a hovering Sea Cobra gunship successfully destroyed a range of live underwater mines.

As of March 2009, Northrop Grumman completed the initial phase of RAMICS testing for introduction into the fleet.

DARPA awarded contracts to Northrop Grumman and General Dynamics Electric Boat in late 2006.

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.

[11]A prototype ship named the Ghost, uses supercavitation to propel itself atop two struts with sharpened edges.

It operates fully submerged with wedge-shaped blades to force cavitation on the entire forward face, starting at the leading edge.