Marine Log

November 9, 2006

GD wins Underwater Express contract

General Dynamics Electric Boat has been awarded a $5.7 million contract to support development of the Defense Advanced Research Projects Agency (DARPA)Underwater Express, an undersea transport capable of controllable speeds up to 100 knots through supercavitation. Electric Boat is a wholly owned subsidiary of General Dynamics (NYSE: GD).

The DARPA-funded Underwater Express effort will help determine the feasibility of supercavitation technology to enable a new class of high-speed underwater craft for future littoral missions that could involve the transport of high-value cargo and/or small units of personnel. Supercavitation involves surrounding an object with a bubble that allows it to travel at high speed. This contract contains two options, which if exercised, would bring the cumulative potential value of this contract to $37.1 million.

Supercavitation offers 60-70% reduction in total drag, or over 90% reduction in skin friction, on an underwater body. It can be attained by going fast enough to develop a full vaporous cavity, or it can be induced at lower speeds by ventilating, i.e., injecting gas, into a partially-developed cavity. Although the technology has been applied to weapons with minimal control capability, its application to larger vessels with transport missions will require thorough development. DARPA's goal is to achieve tractable management and control of the dynamics of a supercavitating underwater body so that an eventual system, manned or unmanned, could be envisioned to travel in this state.

The best known current application of supercavitation is Russia's Shkval torpedo.

The Underwater Express Program will demonstrate stable and controllable high-speed underwater transport through supercavitation. The program will investigate and resolve critical technological issues associated with the physics of supercavitation and will culminate in a credible demonstration at a significant scale to prove that a supercavitating underwater craft is controllable at speeds up to 100 knots.