US 5,611,294 A · Multihulled air cushioned marine vehicle

Abstract

An improved multi-hull gas cushion supported marine vehicle that is, in its preferred embodiment, capable of transition to airborne surface effect operation is presented. This marine vehicle, known as SeaCoaster, has optional elongated knife shaped bows that slice into waves, very fine entry and low angle of divergence supporting gas cushions, water rejecting steps that extend high onto the sidehulls, and retractable water stabilizers to insure optimum performance in heavy seas. The retractable water stabilizers are in the form of inverted-T hydrofoils and/or small boat shaped members. Several variations of hydrofoil configurations are presented. It also has special, normally inverted-V shaped, gas cushion and wetdeck aft seals to insure minimum effect of wave impacts in those areas. The gas pressurization system normally includes powered blowers where a flap-like sealing device can be installed to seal gas leakage. This allows a gas pressurizing blower to either maintain cushion gas pressure for minimum draft or evacuate the gas cushion from minimum above water profile. The latter is valuable for patrol boat applications where a minimum radar signature is desired. Connecting ducts between gas cushions can include venturi's that restrict pressure pulses in one gas cushion from traveling to another gas cushion. Retractable or fixed sidewings are optionally proposed to add aerodynamic lift when SeaCoaster is airborne. These sidewings may include outrigger hulls for added stability and improved aerodynamic efficiencies.

Claims45

Dependent claims

In an improved marine vehicle including a propulsion system and with multiple hulls where said multiple hulls are in mechanical communication, the improvement comprising:

port and starboard sidehulls with each sidehull comprising an open bottomed recess that is artificially pressurized with gas from at least one gas pressurization means to thereby form a weight supporting gas cushion when said marine vehicle is waterborne with boundaries of said recess at least partially defined by water contacting substantially rigid sidekeels and a recess aft seal and where, as seen in a calm sea surface water-line with the gas cushions pressurized and the marine vehicle waterborne and moving forward at high speed, the sidehulls are separated by a water clearing wetdeck and are individually substantially boat shaped with narrow bows forward that then diverge, by way of the water contacting substantially rigid sidekeels, and with said sidekeels transforming to more parallel sections over their aft portions and wherein an average total divergence angle of the water contacting sidekeels of said sidehull recess, as measured from the narrow bow to where the sidekeels become more parallel over their aft portions, is on average less than twenty-two degrees and where each of said sidekeels diverges on average over a minimum of one third of its water contacting length going aft from the narrow bow forward to where the sidekeels become more parallel over their aft portions.

In an improved marine vehicle including a propulsion system and with multiple hulls where said multiple hulls are in mechanical communication, the improvement comprising:

an artificially pressurized gas cushion that supports part of marine vehicle weight, when said marine vehicle is waterborne, disposed at least partially in an open bottomed recess in a multiple hull with said multiple hull positioned, at least in part, between port and starboard sidehulls as a third hull that is in mechanical communication with and separated from said port and starboard sidehulls by water clearing wetdecks and where said third hull's open bottomed recess is at least in part defined by water contacting substantially rigid sidekeels and a recess aft seal and where said third hull, as seen in a calm sea surface waterline when the marine vehicle is waterborne and traveling forward at high speed, is individually boat shaped with a narrow bow forward that diverges, by way of the substantially rigid water contacting sidekeels, over at least one third of a water contacting length of said sidekeels going from the narrow bow forward to where the sidekeels develop more parallel sections aft and wherein an average total divergence angle, from the narrow bow forward to where the sidekeels become more parallel, of said sidekeels is less than twenty-two degrees.

In an improved marine vehicle including a propulsion system and with multiple hulls where said multiple hulls are in mechanical communication, the improvement comprising:

port and starboard sidehulls with each sidehull comprising an open bottomed recess that is artificially pressurized with gas from at least one gas pressurization means to thereby form a weight supporting gas cushion when said marine vehicle is waterborne and with boundaries of said recess at least partially defined by substantially rigid water contacting sidekeels and a recess aft seal and where, as seen in a calm sea surface waterline with the marine vehicle waterborne and moving forward at high speed, the sidehulls are separated by a water clearing wetdeck and are each substantially boat shaped with narrow bows that then diverge by way of the substantially rigid water contacting sidekeels such that an average total divergence angle of the sidekeels of each sidehull is less than 22 degrees and wherein said sidekeels then become more parallel from at least one third of a distance aft of the narrow bow forward and which further comprises a port and a starboard sidewing with said port and starboard sidewings extending outward beyond their respective port and starboard sidehulls such that, when the improved marine vehicle is at least partially airborne, said sidewings provide much of the aerodynamic lift required to keep the improved marine vehicle at least partially airborne.

Dependencies are inferred from the claim text.

Multihulled air cushioned marine vehicle

Life of this patent

Multihulled air cushioned marine vehicle

Life of this patent

Abstract

Claims45