The striking appearance of the remarkable GHOST high-speed attack craft revealed to the public last year by Juliet Marine Systems, Inc., (JMS) of Portsmouth, NH, applies supercavitation technology to offer new capabilities in high speed craft performance.
Caption: GHOST, at rest with hull immersed during recent sea trials.
Image credit: PRNewsFoto/Juliet Marine Systems, Inc.
Although few propulsion details have been released what we do know is that the vessel has a centre hull and two movable sponsons allowing the main hull to run clear of the surface at higher speeds. At rest the sponsons move horizontally outward allowing the center hull to lower and float on the surface: thereby allowing the crew and cargo or passengers to embark / disembark.
At speed the wings carrying the sponsons move to a position approximately 30 degrees from vertical raising the center hull clear of the water surface.
Despite the scant details of the propulsion system as yet made public, propulsion power is provided by “gas turbines.” Looking at the material available, there are large grilles on the side of the main hull, suggesting that behind them the gas turbine are located - probably two in number, possibly driving generators.
Caption: GHOST showing the torpedo-like sponsons
Image credit: PRNewsFoto/Juliet Marine Systems, Inc.
The sponsons somewhat resemble the shape used in some SWATH designs but are perfectly round like a torpedo. I’m guessing but probably within the torpedo shaped sponsons are electric motors powering pulling propellers, perhaps counter-rotating. As to the supercavitation technology, the Soviet Union developed a supercavitating torpedo in the 1970's called Shkval (Russian for squall), with a speed in excess of 200 kn. It is rocket powered and ducts some of the exhaust gases to the front of the torpedo so it slides through the water in a gas bubble cloud. JMS however, is not claiming speeds anything like this but in the absence of detail, perhaps ducting the gas turbine’s exhaust gases to the torpedo, is part of the “secret” of GHOST - time will tell!
Caption: Artists impression of GHOST at speed.
Image credit: Juliet Marine Systems, Inc.