WO2012135718A1 - High speed surface craft and submersible vehicle - Google Patents

High speed surface craft and submersible vehicle Download PDF

Info

Publication number
WO2012135718A1
WO2012135718A1 PCT/US2012/031607 US2012031607W WO2012135718A1 WO 2012135718 A1 WO2012135718 A1 WO 2012135718A1 US 2012031607 W US2012031607 W US 2012031607W WO 2012135718 A1 WO2012135718 A1 WO 2012135718A1
Authority
WO
WIPO (PCT)
Prior art keywords
hull
water
propeller
submersible vessel
craft
Prior art date
Application number
PCT/US2012/031607
Other languages
English (en)
French (fr)
Inventor
Gregory E. Sancoff
Original Assignee
Juliet Marine Systems, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US13/212,767 external-priority patent/US8857365B2/en
Priority claimed from PCT/US2011/052642 external-priority patent/WO2013043171A2/en
Application filed by Juliet Marine Systems, Inc. filed Critical Juliet Marine Systems, Inc.
Priority to CA2831921A priority Critical patent/CA2831921A1/en
Priority to JP2014502861A priority patent/JP2014512300A/ja
Priority to EP12763732.0A priority patent/EP2691290A4/en
Priority to AU2012236188A priority patent/AU2012236188B2/en
Priority to KR1020137028795A priority patent/KR20140079746A/ko
Publication of WO2012135718A1 publication Critical patent/WO2012135718A1/en
Priority to IL228628A priority patent/IL228628A0/en

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63G—OFFENSIVE OR DEFENSIVE ARRANGEMENTS ON VESSELS; MINE-LAYING; MINE-SWEEPING; SUBMARINES; AIRCRAFT CARRIERS
    • B63G8/00—Underwater vessels, e.g. submarines; Equipment specially adapted therefor
    • B63G8/001—Underwater vessels adapted for special purposes, e.g. unmanned underwater vessels; Equipment specially adapted therefor, e.g. docking stations
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63G—OFFENSIVE OR DEFENSIVE ARRANGEMENTS ON VESSELS; MINE-LAYING; MINE-SWEEPING; SUBMARINES; AIRCRAFT CARRIERS
    • B63G8/00—Underwater vessels, e.g. submarines; Equipment specially adapted therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B1/00—Hydrodynamic or hydrostatic features of hulls or of hydrofoils
    • B63B1/32—Other means for varying the inherent hydrodynamic characteristics of hulls
    • B63B1/34—Other means for varying the inherent hydrodynamic characteristics of hulls by reducing surface friction
    • B63B1/38—Other means for varying the inherent hydrodynamic characteristics of hulls by reducing surface friction using air bubbles or air layers gas filled volumes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B71/00—Designing vessels; Predicting their performance
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63G—OFFENSIVE OR DEFENSIVE ARRANGEMENTS ON VESSELS; MINE-LAYING; MINE-SWEEPING; SUBMARINES; AIRCRAFT CARRIERS
    • B63G8/00—Underwater vessels, e.g. submarines; Equipment specially adapted therefor
    • B63G8/08—Propulsion
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63G—OFFENSIVE OR DEFENSIVE ARRANGEMENTS ON VESSELS; MINE-LAYING; MINE-SWEEPING; SUBMARINES; AIRCRAFT CARRIERS
    • B63G8/00—Underwater vessels, e.g. submarines; Equipment specially adapted therefor
    • B63G8/14—Control of attitude or depth
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63G—OFFENSIVE OR DEFENSIVE ARRANGEMENTS ON VESSELS; MINE-LAYING; MINE-SWEEPING; SUBMARINES; AIRCRAFT CARRIERS
    • B63G8/00—Underwater vessels, e.g. submarines; Equipment specially adapted therefor
    • B63G8/14—Control of attitude or depth
    • B63G8/20—Steering equipment
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63G—OFFENSIVE OR DEFENSIVE ARRANGEMENTS ON VESSELS; MINE-LAYING; MINE-SWEEPING; SUBMARINES; AIRCRAFT CARRIERS
    • B63G8/00—Underwater vessels, e.g. submarines; Equipment specially adapted therefor
    • B63G8/36—Adaptations of ventilation, e.g. schnorkels, cooling, heating, or air-conditioning
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H1/00—Propulsive elements directly acting on water
    • B63H1/02—Propulsive elements directly acting on water of rotary type
    • B63H1/12—Propulsive elements directly acting on water of rotary type with rotation axis substantially in propulsive direction
    • B63H1/14—Propellers
    • B63H1/18—Propellers with means for diminishing cavitation, e.g. supercavitation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H25/00—Steering; Slowing-down otherwise than by use of propulsive elements; Dynamic anchoring, i.e. positioning vessels by means of main or auxiliary propulsive elements
    • B63H25/44—Steering or slowing-down by extensible flaps or the like
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H5/00—Arrangements on vessels of propulsion elements directly acting on water
    • B63H5/07—Arrangements on vessels of propulsion elements directly acting on water of propellers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42—AMMUNITION; BLASTING
    • F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
    • F42B10/00—Means for influencing, e.g. improving, the aerodynamic properties of projectiles or missiles; Arrangements on projectiles or missiles for stabilising, steering, range-reducing, range-increasing or fall-retarding
    • F42B10/32—Range-reducing or range-increasing arrangements; Fall-retarding means
    • F42B10/38—Range-increasing arrangements
    • F42B10/42—Streamlined projectiles
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42—AMMUNITION; BLASTING
    • F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
    • F42B19/00—Marine torpedoes, e.g. launched by surface vessels or submarines; Sea mines having self-propulsion means
    • F42B19/12—Propulsion specially adapted for torpedoes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F42—AMMUNITION; BLASTING
    • F42B—EXPLOSIVE CHARGES, e.g. FOR BLASTING, FIREWORKS, AMMUNITION
    • F42B19/00—Marine torpedoes, e.g. launched by surface vessels or submarines; Sea mines having self-propulsion means
    • F42B19/12—Propulsion specially adapted for torpedoes
    • F42B19/125—Torpedoes provided with drag-reducing means
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60F—VEHICLES FOR USE BOTH ON RAIL AND ON ROAD; AMPHIBIOUS OR LIKE VEHICLES; CONVERTIBLE VEHICLES
    • B60F2301/00—Retractable wheels
    • B60F2301/04—Retractable wheels pivotally
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60F—VEHICLES FOR USE BOTH ON RAIL AND ON ROAD; AMPHIBIOUS OR LIKE VEHICLES; CONVERTIBLE VEHICLES
    • B60F3/00—Amphibious vehicles, i.e. vehicles capable of travelling both on land and on water; Land vehicles capable of travelling under water
    • B60F3/0061—Amphibious vehicles specially adapted for particular purposes or of a particular type
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B1/00—Hydrodynamic or hydrostatic features of hulls or of hydrofoils
    • B63B1/02—Hydrodynamic or hydrostatic features of hulls or of hydrofoils deriving lift mainly from water displacement
    • B63B1/10—Hydrodynamic or hydrostatic features of hulls or of hydrofoils deriving lift mainly from water displacement with multiple hulls
    • B63B1/107—Semi-submersibles; Small waterline area multiple hull vessels and the like, e.g. SWATH
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B1/00—Hydrodynamic or hydrostatic features of hulls or of hydrofoils
    • B63B1/02—Hydrodynamic or hydrostatic features of hulls or of hydrofoils deriving lift mainly from water displacement
    • B63B1/10—Hydrodynamic or hydrostatic features of hulls or of hydrofoils deriving lift mainly from water displacement with multiple hulls
    • B63B1/14—Hydrodynamic or hydrostatic features of hulls or of hydrofoils deriving lift mainly from water displacement with multiple hulls the hulls being interconnected resiliently or having means for actively varying hull shape or configuration
    • B63B2001/145—Hydrodynamic or hydrostatic features of hulls or of hydrofoils deriving lift mainly from water displacement with multiple hulls the hulls being interconnected resiliently or having means for actively varying hull shape or configuration having means for actively varying hull shape or configuration
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B1/00—Hydrodynamic or hydrostatic features of hulls or of hydrofoils
    • B63B1/32—Other means for varying the inherent hydrodynamic characteristics of hulls
    • B63B1/34—Other means for varying the inherent hydrodynamic characteristics of hulls by reducing surface friction
    • B63B2001/345—Other means for varying the inherent hydrodynamic characteristics of hulls by reducing surface friction by ejecting friction reducing solids or liquids, e.g. polymers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B1/00—Hydrodynamic or hydrostatic features of hulls or of hydrofoils
    • B63B1/32—Other means for varying the inherent hydrodynamic characteristics of hulls
    • B63B1/34—Other means for varying the inherent hydrodynamic characteristics of hulls by reducing surface friction
    • B63B1/38—Other means for varying the inherent hydrodynamic characteristics of hulls by reducing surface friction using air bubbles or air layers gas filled volumes
    • B63B2001/382—Other means for varying the inherent hydrodynamic characteristics of hulls by reducing surface friction using air bubbles or air layers gas filled volumes by making use of supercavitation, e.g. for underwater vehicles
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B1/00—Hydrodynamic or hydrostatic features of hulls or of hydrofoils
    • B63B1/32—Other means for varying the inherent hydrodynamic characteristics of hulls
    • B63B1/34—Other means for varying the inherent hydrodynamic characteristics of hulls by reducing surface friction
    • B63B1/38—Other means for varying the inherent hydrodynamic characteristics of hulls by reducing surface friction using air bubbles or air layers gas filled volumes
    • B63B2001/387—Other means for varying the inherent hydrodynamic characteristics of hulls by reducing surface friction using air bubbles or air layers gas filled volumes using means for producing a film of air or air bubbles over at least a significant portion of the hull surface
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63G—OFFENSIVE OR DEFENSIVE ARRANGEMENTS ON VESSELS; MINE-LAYING; MINE-SWEEPING; SUBMARINES; AIRCRAFT CARRIERS
    • B63G8/00—Underwater vessels, e.g. submarines; Equipment specially adapted therefor
    • B63G8/001—Underwater vessels adapted for special purposes, e.g. unmanned underwater vessels; Equipment specially adapted therefor, e.g. docking stations
    • B63G2008/002—Underwater vessels adapted for special purposes, e.g. unmanned underwater vessels; Equipment specially adapted therefor, e.g. docking stations unmanned
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63G—OFFENSIVE OR DEFENSIVE ARRANGEMENTS ON VESSELS; MINE-LAYING; MINE-SWEEPING; SUBMARINES; AIRCRAFT CARRIERS
    • B63G13/00—Other offensive or defensive arrangements on vessels; Vessels characterised thereby
    • B63G13/02—Camouflage
    • B63G2013/027—Camouflage using stealth design, i.e. superstructures, hulls, or other vessel's components shaped or constructed for minimizing reflection of radar or sonar beams, or the like
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H1/00—Propulsive elements directly acting on water
    • B63H1/02—Propulsive elements directly acting on water of rotary type
    • B63H1/12—Propulsive elements directly acting on water of rotary type with rotation axis substantially in propulsive direction
    • B63H1/14—Propellers
    • B63H1/18—Propellers with means for diminishing cavitation, e.g. supercavitation
    • B63H2001/185—Surfacing propellers, i.e. propellers specially adapted for operation at the water surface, with blades incompletely submerged, or piercing the water surface from above in the course of each revolution
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H5/00—Arrangements on vessels of propulsion elements directly acting on water
    • B63H2005/005—Front propulsors, i.e. propellers, paddle wheels, or the like substantially arranged ahead of the vessels' midship section
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H21/00—Use of propulsion power plant or units on vessels
    • B63H21/20—Use of propulsion power plant or units on vessels the vessels being powered by combinations of different types of propulsion units
    • B63H2021/202—Use of propulsion power plant or units on vessels the vessels being powered by combinations of different types of propulsion units of hybrid electric type
    • B63H2021/207—Use of propulsion power plant or units on vessels the vessels being powered by combinations of different types of propulsion units of hybrid electric type the second power unit being a gas turbine
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H21/00—Use of propulsion power plant or units on vessels
    • B63H21/20—Use of propulsion power plant or units on vessels the vessels being powered by combinations of different types of propulsion units
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63H—MARINE PROPULSION OR STEERING
    • B63H5/00—Arrangements on vessels of propulsion elements directly acting on water
    • B63H5/07—Arrangements on vessels of propulsion elements directly acting on water of propellers
    • B63H5/08—Arrangements on vessels of propulsion elements directly acting on water of propellers of more than one propeller
    • B63H5/10—Arrangements on vessels of propulsion elements directly acting on water of propellers of more than one propeller of coaxial type, e.g. of counter-rotative type
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T70/00—Maritime or waterways transport
    • Y02T70/10—Measures concerning design or construction of watercraft hulls
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T70/00—Maritime or waterways transport
    • Y02T70/50—Measures to reduce greenhouse gas emissions related to the propulsion system
    • Y02T70/5218—Less carbon-intensive fuels, e.g. natural gas, biofuels
    • Y02T70/5236—Renewable or hybrid-electric solutions

Definitions

  • This invention relates to marine vessels in general, and more particularly to high-speed attack and reconnaissance craft.
  • Zodiac-type craft are not capable of maintaining a reliable defensive perimeter so far out from the battle group. In practice, with Zodiac-type craft, the defensive perimeter must generally be maintained much closer to the battle group, with the consequent loss of reaction time.
  • attack helicopters might be used to protect a naval battle group when it is at sea or at anchor.
  • attack helicopters generally have relatively limited range and, perhaps more importantly, relatively limited sortie time, which effectively prevents them from maintaining a reliable defensive perimeter a substantial distance out from the battle group.
  • attack helicopters generally have substantial radar, infrared and visual "signatures", thereby making them
  • the craft should provide a stable
  • the craft should be capable of remaining on station for a substantial period of time, in order to maintain a reliable defensive perimeter at a safe distance from the battle group.
  • the craft should also be capable of "stealth mode" operation, i.e., it should have small radar, infrared, visual and noise signatures, thereby making it difficult to detect and target.
  • a new and improved submersible vehicle e.g., submarine, torpedo, unmanned drone, etc. which is capable of moving through the water at high speeds .
  • the novel attack craft is small, fast, highly-maneuverable and heavily-armed .
  • the novel attack craft provides a stable platform even when running at high speed in substantial ocean swells, whereby to minimize physical stress on the crew and to provide a stable weapons platform.
  • the novel attack craft is capable of remaining on station for a substantial period of time, in order to maintain a reliable defensive perimeter at a safe distance from a naval battle group.
  • the novel attack craft provides an effective means for defending against a "small boat swarm", by
  • novel attack craft is also capable of "stealth mode" operation, i.e., it has small radar, infrared, visual and noise signatures, thereby making it difficult to detect and target.
  • novel attack craft also provides an
  • a novel submersible vehicle e.g., submarine, torpedo, unmanned drone, etc. which is capable of moving through the water at high speeds.
  • a marine vessel comprising:
  • first and second buoyant tubular foils and first and second struts for connecting the first and second buoyant tubular foils to the command module, respectively;
  • first and second buoyant tubular foils provide substantially all of the buoyancy required for the marine vessel
  • first and second struts are pivotally connected to the command module and fixedly connected to the first and second buoyant tubular foils, respectively;
  • first and second struts comprise substantially rigid planar structures.
  • a marine vessel comprising: a command module;
  • first and second buoyant tubular foils and first and second struts for connecting the first and second buoyant tubular foils to the command module, respectively;
  • first and second buoyant tubular foils provide substantially all of the buoyancy required for the marine vessel
  • the marine vessel further comprises first and second engines enclosed within the first and second buoyant tubular foils, respectively, and first and second propulsion units connected to the first and second engines, respectively, for moving the marine vessel through the water.
  • a marine vessel comprising:
  • first and second buoyant tubular foils and first and second struts for connecting the first and second buoyant tubular foils to the command module, respectively;
  • first and second buoyant tubular foils provide substantially all of the buoyancy required for the marine vessel
  • the marine vessel further comprises first and second propeller mechanisms mounted on the leading ends of the first and second buoyant tubular foils, respectively, for moving the marine vessel through the water .
  • a marine vessel comprising:
  • first and second buoyant tubular foils and first and second struts for connecting the first and second buoyant tubular foils to the command module, respectively;
  • first and second buoyant tubular foils provide substantially all of the buoyancy required for the marine vessel
  • the marine vessel further comprises a plurality of spoilers mounted on the first and second buoyant tubular foils for steering the marine vessel as it moves through the water.
  • a marine vessel comprising:
  • a propeller mechanism mounted on the leading end of the buoyant tubular foil for moving the marine vessel through the water.
  • a marine vessel comprising:
  • a marine vessel comprising:
  • a propeller mechanism mounted on the leading end of the buoyant tubular foil for moving the marine vessel through the water
  • each of the spoilers comprises a plate movable between (i) an inboard position wherein the plate is substantially aligned with the skin of the buoyant tubular foil to which the spoiler is mounted, and (ii) an outboard position wherein the plate projects into, and deflects, the water flowing by the buoyant tubular foil to which the spoiler is mounted.
  • a method for moving through water comprising:
  • a marine vessel comprising:
  • first and second buoyant tubular foils and first and second struts for connecting the first and second buoyant tubular foils to the command module, respectively;
  • first and second buoyant tubular foils provide substantially all of the buoyancy required for the marine vessel; wherein the first and second struts are pivotally connected to the command module and fixedly connected to the first and second buoyant tubular foils, respectively;
  • first and second struts comprise substantially rigid planar structures
  • a method for moving through water comprising:
  • a marine vessel comprising:
  • first and second buoyant tubular foils and first and second struts for connecting the first and second buoyant tubular foils to the command module, respectively;
  • first and second buoyant tubular foils provide substantially all of the buoyancy required for the marine vessel
  • the marine vessel further comprises first and second engines enclosed within the first and second buoyant tubular foils, respectively, and first and second propulsion units connected to the first and second engines, respectively, for moving the marine vessel through the water; and
  • a method for moving through water comprising:
  • a marine vessel comprising:
  • first and second buoyant tubular foils and first and second struts for connecting the first and second buoyant tubular foils to the command module, respectively;
  • first and second buoyant tubular foils provide substantially all of the buoyancy required for the marine vessel
  • the marine vessel further comprises first and second propeller mechanisms mounted on the leading ends of the first and second buoyant tubular foils, respectively, for moving the marine vessel through the water; and
  • a method for moving through water comprising:
  • a marine vessel comprising:
  • first and second buoyant tubular foils and first and second struts for connecting the first and second buoyant tubular foils to the command module, respectively; wherein the first and second buoyant tubular foils provide substantially all of the buoyancy required for the marine vessel;
  • the marine vessel further comprises a plurality of spoilers mounted on the first and second buoyant tubular foils for steering the marine vessel as it moves through the water;
  • a method for moving through water comprising:
  • a marine vessel comprising:
  • a propeller mechanism mounted on the leading end of the buoyant tubular foil for moving the marine vessel through the water
  • a method for moving through water comprising:
  • a marine vessel comprising:
  • a method for moving through water comprising:
  • a marine vessel comprising:
  • a propeller mechanism mounted on the leading end of the buoyant tubular foil for moving the marine vessel through the water
  • each of the spoilers comprises a plate movable between (i) an inboard position wherein the plate is substantially aligned with the skin of the buoyant tubular foil to which the spoiler is mounted, and (ii) an outboard position wherein the plate projects into, and deflects, the water flowing by the buoyant tubular foil to which the spoiler is mounted;
  • a marine vessel comprising:
  • first and second propellers mounted on a forward end of said vehicle and adapted in operation to move said vehicle through water; said first and second propellers comprising leading and trailing propellers;
  • leading and trailing propellers are adapted to rotate in opposite directions to each other simultaneously;
  • a marine vessel comprising:
  • propeller means mounted on a forward end of said vehicle
  • said propeller means being operable to move said vehicle through water and to produce super-cavitated water for flow aft of said propeller means and
  • a marine vessel comprising:
  • first and second buoyant tubular foils are first and second buoyant tubular foils
  • first and second struts connecting said first and second foils to said command module; wherein said first and second foils provide all buoyancy required for the vessel;
  • struts are each pivotally connected to said command module and to one of said foils;
  • first and second struts comprising generally rigid planar structures
  • first and second propellers mounted on forward ends of said foils for moving the vessel through water ;
  • first and second propellers comprise leading and trailing propellers
  • leading and trailing propellers rotate in opposite directions to create air skirts around the foils and extending along lengths of the foils to decrease foil surface friction.
  • a marine vessel comprising:
  • a propeller mounted on a forward end of said vehicle and adapted in operation to move said vehicle through water;
  • said propeller being of a size and configuration to provide propeller generated super-cavitated water flowing from said propeller and thence along an outer surface of said vehicle;
  • a marine vessel comprising:
  • first and second buoyant tubular foils and first and second struts for connecting the first and second buoyant tubular foils to the command module, respectively;
  • first and second buoyant tubular foils provide substantially all buoyancy required for the marine vessel
  • the marine vessel further comprises first and second propeller mechanisms mounted on the forward ends of the first and second buoyant tubular foils, respectively, for moving the marine vessel through water; and
  • a method for moving through water comprising:
  • a marine vessel comprising:
  • a propeller mechanism mounted on the forward end of the buoyant tubular foil for moving the marine vessel through the water
  • a method for moving through water comprising:
  • a marine vessel comprising:
  • a propeller mechanism mounted on the forward end of the buoyant tubular foil for moving the marine vessel through water
  • each of the spoilers comprises a plate movable between (i) an inboard position wherein the plate is substantially aligned with a skin of the buoyant tubular foil to which the spoiler is mounted, and (ii) an outboard position wherein the plate projects into, and deflects, water flowing by the buoyant tubular foil to which the spoiler is mounted;
  • an elongated tubular foil for travel through water, the foil being provided with a
  • said propulsion means comprising in part a propeller means rotatably mounted on a forward end of the foil and adapted to move the foil through the water ;
  • said propeller means being adapted to effect supercavitation of water while operative to move the foil through the water;
  • the body in an elongated tubular configuration having a propulsion means rotatably mounted on a forward end of the body and adapted to move the body through the water;
  • an elongated tubular body for travel through water, the elongated tubular body being provided with a propulsion means; said propulsion means comprising in part a propeller means rotatably mounted on a forward end of the elongated tubular body and adapted to move the elongated tubular body through the water;
  • said propeller means being adapted to effect supercavitation of water while operative to move the elongated tubular body through the water to thereby create a skirt of supercavitated water adjacent at least a portion of an outer skin of the elongated tubular body;
  • the body in an elongated tubular configuration having a propulsion means rotatably mounted on a forward end of the body and adapted to move the body through the water;
  • a submersible vessel comprising:
  • At least one propeller mounted on a forward end of said hull and adapted to move said hull through water ;
  • said at least one propeller being of a size and configuration such that when it is rotated at an appropriate speed, it generates supercavitated water flowing from said at least one propeller and thence along an outer surface of said hull so as to diminish friction on the outer surface of said hull and
  • a method for moving through water comprising:
  • At least one propeller mounted on a forward end of said hull and adapted to move said hull through water ;
  • said at least one propeller being of a size and configuration such that when it is rotated at an appropriate speed, it generates supercavitated water flowing from said at least one propeller and thence along an outer surface of said hull so as to diminish friction on the outer surface of said hull and
  • Fig. 1 is a schematic view showing a novel fleet protection attack craft formed in accordance with the present invention
  • Figs. 2-9 are schematic views showing further construction details of the novel attack craft shown in Fig. 1, including further details of its command module, buoyant tubular foils (BTFs) and struts;
  • BTFs buoyant tubular foils
  • Figs. 10-15 are schematic views showing further details of the BTFs and struts, and the internal components thereof;
  • Figs. 15A and 15B are schematic views showing how a gaseous envelope may be provided around the BTFs so as to reduce drag as the vessel moves through the water ;
  • Figs. 16-26 are schematic views showing further details of the spoilers used to steer the novel attack craft and adjust its attitude;
  • Figs. 27-36 are schematic views showing how the position of the struts and BTFs can be adjusted relative to the command module
  • Fig. 37 is a cross-sectional view of a buoyant tubular foil (BTF) having air trap fins disposed on some or all of its periphery, and further shows preferred configurations for the air trap fins - in addition, this view shows a plurality of air outlet holes formed in the hull of the buoyant tubular foil;
  • BTF buoyant tubular foil
  • Fig. 37A is a view similar to that of Fig. 37, but showing a substantially complete array of air trap fins mounted on the outer hull of the buoyant tubular foil (BTF) ;
  • Figs. 37B and 37C are side elevational views of a buoyant tubular foil (BTF) and a strut supporting the buoyant tubular foil, wherein the buoyant tubular foil comprises air trap fins on its periphery, and further wherein the buoyant tubular foil and the supporting strut have a plurality of air outlet holes formed therein;
  • BTF buoyant tubular foil
  • strut supporting the buoyant tubular foil
  • Fig. 37D is a cross-sectional view of a buoyant tubular foil (BTF) having air outlet holes formed therein;
  • Fig. 37E is a schematic view of a buoyant tubular foil (BTF) having a single front propeller mechanism for generating a supercavitated air curtain
  • Fig. 38 is a schematic view of a submarine comprising a buoyant tubular foil (i.e., a tubular hull) equipped with a front pulling propeller
  • Figs. 38A, 38B, 38C and 38D are schematic views of a novel submarine formed in accordance with the present invention.
  • Fig. 39 is a schematic view of a torpedo
  • buoyant tubular foil i.e., a tubular hull
  • front pulling propeller a buoyant tubular foil
  • Fig. 40 is a schematic view of a novel unmanned submersible craft formed in accordance with the present invention.
  • Fig. 41 is a schematic view showing one manner of using the novel unmanned submersible craft shown in Fig. 40.
  • Attack craft 5 generally comprises a command module 100 for carrying a crew, weapons and payload (including passengers) , a pair of buoyant tubular foils (BTFs) 200 for providing buoyancy, propulsion and steering, and a pair of struts 300 for supporting command module 100 on BTFs 200.
  • BTFs buoyant tubular foils
  • struts 300 can be disposed in a variety of different positions vis-a-vis command module 100, so that attack craft 5 can assume a number of different configurations, depending on the desired mode of operation, whereby to provide high speed, extreme stability and stealth capability.
  • attack craft 5 may be placed in the configuration shown in Fig. 4 (i.e., so that struts 300 are disposed approximately 45 degrees off the horizon, and at approximately a right angle to one another) so that command module 100 is safely out of the water and the vessel has modest radar, infrared and visual signatures.
  • attack craft 5 may be placed in the
  • attack craft 5 may be placed in a configuration somewhere between those shown in Figs . 4 and 7.
  • Attack craft 5 is also designed to operate in stealth mode, by lowering its physical profile. In this case, attack craft 5 may be placed in the
  • command module 100 is disposed just above, or actually in, the water, reducing its radar, infrared and visual
  • This mode can be very useful when attack craft 5 is being used for reconnaissance purposes and/or to deliver small teams of special forces behind enemy lines and/or to extract the same.
  • attack craft 5 is normally operated in the
  • attack craft 5 may be operated in the configuration shown in Fig. 7, so that command module 100 stands well clear of any swells. And, when desired, attack craft 5 may be operated in the configuration shown in Fig. 8 so as to assume a stealth mode. Or, attack craft 5 may be operated in a selected configuration somewhere between those shown in Figs. 4 , 7 and 8.
  • SWATH Waterplane Area Twin Hull
  • Hydrofoils have been in experimental use for many years, and today are in active service around the world for a variety of applications. Hydrofoils generally employ small airplane- like wings ("lifting foils") which provide lift for the hull of the vessel. These lifting foils are typically lowered into the water while the vessel is underway. At higher speeds, the lifting foils are capable of lifting the hull of the vessel completely out of the water, thereby allowing the vessel to operate with only its lifting foils (and their supporting struts) in the water, whereby to minimize drag and increase vessel speed. However, the lifting foils themselves provide no buoyancy and therefore cannot support the vessel at slower speeds. Thus, the vessel can only operate in hydrofoil mode when moving at substantial speeds. In addition, due to the thin nature of the hyrdofoil's lifting foils, it is not possible to house the
  • SWATH vessels employ two or more torpedo- shaped structures which are disposed underwater and attached to the main body of the vessel with fixed vertical struts.
  • the torpedo- shaped structures provide
  • SWATH vessels resemble catamarans, except that the two pontoon hulls of the catamaran are replaced by
  • the SWATH design generally provides excellent stability because the underwater torpedo- shaped structures are less affected by wave action than a traditional wave-riding hull.
  • the SWATH design generally provides excellent stability because the underwater torpedo- shaped structures are less affected by wave action than a traditional wave-riding hull.
  • hydromantic shape, of the large underwater torpedo- shaped structures generally result in higher power consumption. This higher power consumption in turn necessitates the use of larger engines and/or results in reduced vessel speed.
  • the use of larger engines is itself problematic, since the engines must then be housed in the hull or, if the engines are to be housed in the underwater torpedo- shaped structures, the underwater torpedo- shaped structures must be enlarged. Housing the engines in the hull introduces all of the power transmission problems discussed above with respect to hydrofoils, inasmuch as the propellers are mounted to the underwater torpedo- shaped
  • the present invention overcomes the problems associated with the prior art through the provision and use of novel fleet protection attack craft 5.
  • Attack craft 5 supports its command module 100 on a pair of buoyant tubular foils (BTFs) 200 via movable struts 300.
  • BTFs 200 normally provide all of the buoyancy required for the craft, with command module 100 remaining completely out of the water. More particularly, BTFs 200 and struts 300 are often the only portions of the craft which contact the water, and they provide low friction hydromantic cross- sections so as to minimize water resistance.
  • BTFs 200 house substantially all of the propulsion, fuel and steering systems for the craft, thereby providing the craft with an unusually low center of gravity and permitting the volume of command module 100 to be dedicated to crew, weapons and payload.
  • struts 300 are movable relative to command module 100, thereby permitting the craft to assume a number of different configurations. This unique approach results in a craft with unparalleled speed and stability regardless of sea conditions, and with lower radar, infrared and visual signatures, thereby making it difficult to detect and target.
  • command module 100 generally comprises a watertight enclosure 105 (Fig. 3) having a hull-like bottom surface 110 (Figs. 4, 5, 7 and 8) .
  • Command module 100 includes a cockpit 115
  • Command module 100 further includes a rear hatch 125 (Figs. 5, 6 and 9) for permitting entry and exit of crew, weapons and payload (including passengers) , and a top hatch 130
  • FIGs. 2, 6 and 9 for permitting various weapons systems to be raised out of bay 120, fired, and then lowered back into bay 120.
  • Command module 100 is armored to protect all occupants, weaponry and payload.
  • Windscreens 135 are arranged to protect all occupants, weaponry and payload.
  • FIGs. 7 and 9 are formed out of bullet-resistant materials .
  • Command module 100 comprises watertight bulkhead enclosures which, combined with hull -like bottom surface 110, allow waves to wash over the command module without effect when attack craft 5 is operating in its stealth mode (see below) .
  • Automatic vent doors seal any open systems against water leakage when attack craft 5 is in this stealth mode.
  • command module 100 is preferably based on so-called "stealth" principals in order to minimize the radar signature of the craft. More particularly, the outer surface of command module 100 is designed to deflect radar energy and return only a minimal amount of radar energy to the radar transmitter. To this end, the exterior surfaces of command module 100 are preferably highly angular, with the angles being selected so as to reflect the radar energy either downward towards the water or upward into the sky. In any case the exterior surfaces of command module 100 minimize the amount of radar energy reflected directly back to the sender. Furthermore, command module 100 preferably incorporates a radar- absorbent paint which is capable of absorbing or further reducing any incident radar energy.
  • Command module 100 is also configured to house all of the control systems for piloting the attack craft, all of the weapons control systems for
  • an auxiliary generator for supplemental power
  • the weapons systems carried by attack craft 5 preferably comprise (i) one 20 mm Vulcan Gatling gun, equipped with optic and night vision; (11) two 30 caliber Miniguns equipped with optic and night vision;
  • the Gatling gun, Miniguns and rockets are housed within bay 120 for elevated deployment through top hatch 130, and the "mini" torpedoes are mounted to the exterior of command module 100, e.g., such as is shown at 140.
  • BTFs Buoyant Tubular Foils
  • a pair of buoyant tubular foils (BTFs) 200 provide buoyancy, propulsion and steering for attack craft 5.
  • Each of the BTFs 200 generally comprises a hollow tubular structure 205 which houses an engine 210 for powering a propeller system 215, a fuel tank 220 for supplying fuel to engine 210, and steering elements (or spoilers) 225 for steering attack craft 5.
  • Hollow tubular structure 205 generally comprises a hollow hull which provides buoyancy for attack craft 5. Hollow tubular structure 205 is configured so as to provide stability at low speed operations while still providing low water friction and an improved hydromantic profile so as to enable speeds of over eighty (80) knots. At high speeds, the configuration of hollow tubular structure 205 provides extraordinary stability for the vessel, due to the flow of water over the elongated tubular structure.
  • hollow tubular structure 205 has a cross-section which is between about 1/10 and about 1/30 of the length of hollow tubular structure 205, and preferably about 1/20 of the length of the hollow tubular structure.
  • excellent performance can be achieved when the hollow tubular structure 205 has a 3 foot outer diameter and a 60 foot length.
  • hollow tubular structure 205 comprises a plurality of disconnectable sections that permit easy access to components disposed within the interior of hollow tubular structure 205, e.g., for maintenance and quick replacement of power and sensor modules.
  • hollow tubular structure 205 can comprise a center section 230 which is mounted to a strut 300, a forward section 235 which is dismountable from center section 230, and a rear section 240 which is dismountable from center section 230.
  • interior components are equipped with slides for easy entry into, and removal from, hollow tubular structure 205.
  • Fig. 14 shows how engine 210 may be equipped with slides 245 for supporting engine 210 within hollow tubular section 205, and to facilitate insertion into, and removal from, hollow tubular structure 205.
  • Foward section 235 and rear section 240 can mount to center section 230 in a variety of ways.
  • the sections can be mechanically held together (e.g., by hydraulics, power screw actions, etc.) or they can twist lock together (e.g., in the manner of a bayonet-type mount) .
  • a watertight seal is provided between the sections so as to ensure hull integrity.
  • the seal can be a
  • hollow tubular structure 205 e.g., a resilient 0- ring having a round or flat cross-section.
  • the 0-ring can be an inflatable seal (e.g., like the inner tube of a bicycle tire) that can provide adjustable sealing forces by the injection of an appropriate amount of fluid (e.g., gas or liquid) .
  • each 0-ring seal has two sealing surfaces, i.e., the face surface between adjacent sections and the face surface against the skin of hollow tubular structure 205.
  • sections of hollow tubular structure 205 permits the rapid servicing and/or replacement of the various components contained within hollow tubular structure 205, e.g., engine 210, fuel tank 220, etc.
  • Engine 210 can be a conventional diesel engine, internal combustion engine, rotary engine, electric motor, etc.
  • engine 210 comprises a gas turbine (jet) engine, e.g., of the sort used in aircraft, and particularly of the sort used in
  • a gas turbine engine is preferred due to its high power, small size and low weight. More particularly, a gas turbine engine typically has a horsepower-to-weight ratio of about 2.5 horsepower (HP) per pound. By comparison, a modern marine diesel engine typically has a horsepower-to-weight ratio of about 0.5 HP per pound. Inasmuch as there is
  • a high power, low weight engine in a high speed craft.
  • a gas turbine engine is the preferred propulsion unit for attack craft 5.
  • a gas turbine engine is also ideal for use in attack craft 5 inasmuch as its size and configuration are perfectly suited for disposition within hollow tubular structure 205. More
  • gas turbine engines typically have an elongated, somewhat cylindrical configuration which easily fits within a hollow tubular structure.
  • gas turbine engines generally have relatively modest cross-sections, such that the gas turbine engines can fit within a relatively small diameter tube.
  • T53L13 gas turbine (jet) engine manufactured by Lycoming Engines (a division of Avco Corporation, a wholly owned subsidiary of Textron, Inc.) of
  • PA has a diameter which is ideally suited for disposition within hollow tubular structure 205 of attack craft 5.
  • the gas turbine engine provides a starter generator that performs two functions, i.e., (i) to start the turbine engine, and (ii) to generate DC power. More particularly, most gas turbine engines provide 24 volts DC at 300 amps. This allows attack craft 5 to power all of its electrical systems from the gas turbine engines, with the need for only a small supplemental generator for charging batteries. In addition, placing a gas turbine engine inside hollow tubular structure 205, which is always
  • gas turbine engines are generally designed to be quickly and easily removed (e.g., by sliding) from an aircraft fuselage. Similarly, the gas turbine engine can be quickly and easily removed
  • hollow tubular structure 205 (e.g., by sliding) from hollow tubular structure 205.
  • the gas turbine engine usually has a high
  • a gearbox 250 using planetary gears connects engine 210 to propeller system 215. This approach provides a gearbox which is smaller than the outside diameter of the gas turbine engine .
  • the "Achilles heel" of a gas turbine engine is its need to rapidly intake large quantities of fresh air and to rapidly expel large quantities of exhaust air.
  • gas turbine engines have not heretofore been a candidate for use in underwater structures (e.g., submarines and the submerged portions of SWATH vessels) due to the inability to adequately aspirate the jet engines.
  • attack craft 5 A critical aspect of attack craft 5 is the air intake and exhaust systems which support the use of gas turbine engines underwater.
  • the design of the air intake and exhaust systems is complicated by the fact that attack craft 5 is designed to change configurations (e.g., as shown in Figs. 4, 7 and 8) and the air intake and exhaust systems must be able to accommodate these configuration changes.
  • the gas turbine engines are housed underwater in BTFs 200, the BTFs 200 are disposed at the ends of struts 300, and struts 300 are movable relative to command module 100 (see Figs. 4, 7 and 8) .
  • the air intake and exhaust systems of attack craft 5 must be capable of rapidly moving large quantities of air in and out of the gas turbine engines, and through struts 300, while at the same time accommodating movement of struts 300 relative to command module 100.
  • attack craft 5 comprises an air intake and exhaust system for rapidly delivering large quantities of fresh air to gas turbine engine 210 and for rapidly expelling large quantities of exhaust air from gas turbine engine 210.
  • the air intake and exhaust system generally comprises an engine intake duct 255 and an engine exhaust duct 260.
  • the intake side of engine intake duct 255 is disposed in command module 100 so that it can access cool air, which increases the efficiency of gas turbine engines 210.
  • the intake side of engine intake duct 255 is funneled so as to generate ram air forces while attack craft 5 is moving at speed, which further increases the efficiency of gas turbine engines 210.
  • the outlet side of engine exhaust duct 260 is disposed in command module 100 so as to provide efficient exhaust venting with a minimal heat signature.
  • Engine intake duct 255 and engine exhaust duct 260 preferably pass through a flexible coupling located at the junction of the strut and the command module, in order to accommodate movement of the strut vis-a-vis the command module. This flexible coupling also
  • struts 300 accommodates other lines passing from command module 100 to BTFs 200 via struts 300, e.g., fuel re-fill lines, electrical power lines, electrical control lines, etc.
  • the flexible coupling is configured so as to allow engine intake and engine exhaust to be vectored and bent while still accommodating the large gas volumes associated with the gas turbine engine. Furthermore, the flexible coupling is designed to accommodate the high exhaust temperatures created by the gas turbine engine. The use of heat-resistant flexible materials in the coupling is essential to allow movement of the struts relative to the command module.
  • engine exhaust duct 260 is routed inside air intake duct 255 so as to allow the exhaust to be cooled by the intake air, whereby to provide a lower thermal signature for attack craft 5.
  • engine exhaust duct 260 is not routed inside air intake duct 255 - rather, in this form of the invention, engine exhaust duct 260 is separate from air intake duct 255, and the exhaust in engine exhaust duct 260 is
  • insulation may be used to keep the cool air in air intake duct 255 from being heated by the hot exhaust in engine exhaust duct 260 in order to increase the efficiency of gas turbine engines 210.
  • engine exhaust duct 260 includes insulation to prevent the heat of gas turbine engine 210 from overheating the outer skin of strut 300.
  • engine exhaust ducts 260 are double-walled, so as to allow a fluid to be circulated around the inner hot duct, whereby to further cool the engine exhaust and provide a lower thermal signature.
  • attack craft 5 also includes an electric motor (not shown) and batteries (not shown) for selectively driving propeller system 215. More particularly, in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e.g., in certain circumstances (e., in certain circumstances (e., in certain circumstances (e.g., in certain circumstances
  • propellers move through, stern-mounted, pushing propellers are generally impractical for high speed craft .
  • hydroplanes and ocean racing boats use stern-mounted, surface-penetrating, forward- facing propellers that ride partially submerged in agitated water with air mixed in.
  • These piercing propellers are designed with a heavy trailing edge and anti -cavitation cupping. These piercing propellers withstand the extreme forces of high horsepower and high rpm because the propeller is never fully engaged in the water.
  • the present invention utilizes a propeller system 215 which comprises a pair of
  • a propeller system 215 is placed at the bow of each BTF 200 so that the forward- facing, pulling propellers can "bite” into virgin water, whereby to obtain maximum efficiency.
  • each propeller system 215 comprises two propellers, a leading propeller 265 and a trailing propeller 270, operated in a timed, counter-rotating mode, so as to provide reduced cavitation for the forward propeller.
  • Leading propeller 265 is the main propulsion element and does the majority of the work of pulling of the vessel.
  • Trailing propeller 270 spins in the opposite direction from the leading propeller and evacuates water from behind the leading propeller, thereby permitting the leading propeller to work with maximum efficiency.
  • propeller 270 moves water out from behind leading propeller 265 so that the leading propeller can pull more water in. This provides increased propeller efficiency, which translates into higher speed and lower fuel consumption.
  • propellers 265, 270 also permits smaller propeller diameters to be used. This is because the surface areas of the two propellers combine so as to provide an overall effective surface area which is equivalent to the surface area of a single, larger diameter propeller. However, it is difficult to rotate a large diameter propeller at high speeds due to the forces involved. Thus, the use of serially-mounted, counter- rotating propellers permits the propellers to be rotated at higher rpms, thereby permitting higher speeds to be achieved.
  • side torque in propellers is the result of the centrifugal forces created by the rotation of the propeller. This side torque creates a tendency for the vessel to turn in the direction of the rotation of the blade. Side torque is not desired with attack craft 5, since it involves a loss of energy and can create steering issues for the vessel.
  • a gearbox 250 connects a gas turbine engine 210 to a propeller system 215. More particularly, gearbox
  • the 250 is configured to convert the single rotational motion of the output shaft of a gas turbine engine 250 into the dual, co-axial, counter-rotational motions needed to drive the counter-rotating propellers, 265, 270.
  • the propellers are able to pull the vessel through clean, undisturbed, virgin water, thereby ensuring optimal propeller performance.
  • the two propellers are able to pull the vessel through clean, undisturbed, virgin water, thereby ensuring optimal propeller performance.
  • attack craft 5 is able to generate a highly gaseous environment, comprising a jet stream of dense collapsing bubbles, that
  • Attack craft 5 can also include additional means for producing an encompassing gaseous envelope. More particularly, a plurality of small holes 275 (Fig. 15B) are preferably located immediately behind
  • trailing propeller 270 and disposed in a circler fashion about the periphery of the BTF structure.
  • holes 275 are in communication with ductwork leading to the outside air, allowing the trailing propeller to create a siphon effect, drawing air down for release just aft of the trailing propeller, whereby to create an even more dense gaseous envelope for reducing BTF friction.
  • a siphon effect drawing air down for release just aft of the trailing propeller, whereby to create an even more dense gaseous envelope for reducing BTF friction.
  • pressurized gas source connected to small holes 275 can also be used to release gas immediately aft of the trailing propeller, whereby to create the desired gaseous envelope for reducing BTF friction.
  • a supply of friction- reducing fluid e.g., detergent
  • Conventional rudders are continuously deployed in the water, so that they create friction and drag not only when being manipulated so as to change the direction of the vessel, but also under normal
  • attack craft 5 provides forward and aft steering elements (or spoilers) 225 that are projectable from, and retractable into, the outer skin of hollow tubular structure 205. In this respect it should be
  • each of the spoilers 225 can be projected an adjustable amount outboard from hollow tubular structure 205.
  • command module 100 can be provided with various control systems which permit each of the spoilers 225 to be operated in a coordinated fashion or, if desired, independently from one another.
  • sixteen spoilers 225 are provided: four spoilers 225 at the front of each BTF 200 and four spoilers 225 at the rear of each BTF 200, with spoilers 225 being disposed at the "12 o'clock", “3 o'clock”, “6 o'clock”, and “9 o'clock” positions.
  • This arrangement allows spoilers 225 to apply left, right, up and/or down forces (or any combination thereof) to the front and/or rear of each of the BTFs 200 while attack craft 5 is underway.
  • spoilers 225 provide substantially no drag when the vessel is underway and no directional changes are needed - this is because the spoilers then reside flush with the outer skins of hollow tubular structures 205.
  • Spoilers 225 impose drag on the vessel only when they are extended outwardly from the skins of hollow tubular structures 205, whereby to provide the forces necessary to maneuver the vessel - and they are thereafter returned to their inboard (i.e., flush, and no-drag) positions as soon as the maneuver is completed and the vessel returns to standard forward motion.
  • spoilers 225 on the fore and aft portions of hollow tubular structures 205 permits the application of more dramatic turning forces. More particularly, by setting a fore spoiler to turn in one direction and a corresponding aft spoiler to turn in the opposite direction, significant turning forces can be quickly and easily applied to the vessel using spoilers of relatively modest size. Thus, course corrections can be effected quickly, making the vessel extremely agile, while permitting the turning friction of the spoilers to be applied only for short durations.
  • Spoilers 225 can be used for turning left or right (see Figs. 16-19), for adjusting the trim (i.e. the up/down attitude) of the vessel (see Figs. 20-23) and/or to enhance deceleration of the vessel (see Figs . 24-26) .
  • Spoilers 225 can be flush plates that protrude from the outer skins of hollow tubular structures 205 and cause friction when needed to change direction.
  • spoilers 225 can be made of an
  • elastomeric material that can be inflated with air, fluids, etc. and which protrude from the outer skins of hollow tubular structures 205.
  • Fuel tanks 220 are housed inside BTFs 200, preferably in the center section 230.
  • Fuel tanks 220 preferably comprise double-walled tanks made of a flexible bladder material (e.g., a flexible bladder disposed inside another flexible bladder) . This arrangement allows for a fluid (e.g., seawater) to be pumped into the outer bladder in order to compensate for the consumption of fuel from within the inside bladder, thereby ensuring that the buoyancy of the attack craft remains constant .
  • a fluid e.g., seawater
  • the center of gravity for attack craft 5 is intended to be as low as possible, in order to
  • connecting struts 300 attach BTFs 200 to command module 100.
  • struts 300 are designed to be fixed to BTFs 200 and pivot on command module 100 so as to allow attack craft 5 to assume different configurations (Figs. 4, 7 and 8) , whereby to permit command module 100 to sit different distances from the water.
  • struts 300 comprise hydraulic or electric jack screws 305 connected to load arms located within struts 300, whereby to move struts 300 relative to command module 100.
  • Figs. 27-29 show struts 300 in a position corresponding to the attack craft
  • Figs. 30-32 show struts 300 in a position corresponding to the attack craft configuration shown in Fig. 7, and Figs. 33-36 show struts 300 in a position corresponding to the attack craft configuration shown in Fig. 8.
  • struts 300 extend into the water, it is important to keep the struts as thin as possible so as to minimize drag.
  • struts 300 relies primarily on the strength of the load arms located within the struts acting in conjunction with the outer skin of the struts, while using minimal internal frames. This is important, since struts 300 need to have large areas of uninterrupted volume in order to permit engine intake to pass uninterrupted through the interior of the struts.
  • sensors are located on hull -like bottom surface 110 of command module 100 and continuously measure the distance of the command module from the water surface.
  • a computer automatically adjusts the disposition of struts 300 so as to maintain the command module a desired distance above the water surface.
  • attack craft 5 may be placed in the configuration shown in Fig. 4 so that command module 100 is safely out of the water and the vessel has modest radar, infrared and visual signatures .
  • attack craft 5 may be placed in the
  • attack craft 5 may be placed in a selected configuration between those shown in Figs. 4 and 7.
  • Attack craft 5 is also designed to operate in stealth mode, by lowering its physical profile. In this case, attack craft 5 may be placed in the
  • command module 100 sits just above, or actually in, the water, reducing its radar, infrared and visual signatures. This mode can be very useful when attack craft 5 is being used for reconnaissance purposes and/or to deliver small teams of special forces behind enemy lines and/or to extract the same.
  • attack craft 5 is normally operated in the
  • attack craft 5 may be operated in the configuration shown in Fig. 7, so that command module 100 stands well clear of any swells. And, when desired, attack craft 5 can be operated in the configuration shown in Fig. 8 so as to assume a stealth mode.
  • attack craft 5 may be operated in a selected configuration between those shown in Figs. 4, 7 and 8.
  • speed sensors feed speed data to a main computer, which adjusts the sensitivity of the steering controls so that, while travelling at low speeds, the controls are more reactive and when travelling at high speeds, the controls are less reactive.
  • main computer which adjusts the sensitivity of the steering controls so that, while travelling at low speeds, the controls are more reactive and when travelling at high speeds, the controls are less reactive.
  • the steering controls e.g., a joystick
  • large movements of the steering controls e.g., a joystick
  • small movements of the steering controls are required at slow speeds to make
  • BTFs 200 can be provided with an extendible boom.
  • This boom is deployable from the trailing end of the BTF, and is preferably flexible.
  • the extendible boom can serve two purposes .
  • the extendible boom can have controllable surface protrusions along its length that can be enlarged or contracted so as to allow drag to be applied to the boom, thus further stabilizing the BTF in a manner similar to the tail of a kite.
  • the protrusions cause drag that stabilizes the vessel in both the horizontal and vertical planes.
  • protrusions can be controlled by elastic bladders which are inflated so as to increase size (and hence drag) as desired, or a mechanical device located at the end of the boom that provides mechanical drag resistance, thereby increasing stability.
  • the extendible boom can also house sonar, listening devices, magnetometers, gravity interruption sensors, etc. that can be used for the identification of submerged objects. By mounting these devices on the end of an extendible boom, the devices can be isolated from the remainder of attack craft 5, so as to minimize interference with device function.
  • the BTF For Constraining Movement Of The Supercavitated Air Skirt Relative To The Hull Of The
  • buoyant tubular foil BTF
  • the air skirt is created around the hull of the buoyant tubular foil (BTF) by propeller-generated supercavitation and, optionally, by ejecting air through the hull and into the flow of water around the hull.
  • the hull is provided with many air outlet holes 405 for ejecting air out of the hull and supplementing the propeller-generated supercavitation bubble stream.
  • these air outlet holes 405 extend horizontally along the length of the buoyant tubular foil 200, ensuring that the air curtain covers substantially the entire length of the hull of BTF 200. See Figs. 37 and 37A-37C.
  • Air ejection holes 405 may also be provided on struts 300, e.g., on the leading edge of the struts (see Figs. 37, 37B and 37C) .
  • the hull of BTF 200 is also provided with a plurality of horizontally-extending air trap fins 410.
  • Air trap fins 410 channel the air bubbles along the length of the hull and retard movement of the air bubbles away from the hull. See Figs. 37 and 37A-37C.
  • air trap fins 410 may be
  • air trap fins 410 may be
  • Air trap fins 410 may be of a scallop-type design, thereby providing recessed channels along the hull of the BTF, whereby to hold the air against the hull of the BTF.
  • This water-flow boundary comprises a water density gradient extending between dense sea water (spaced from the BTF) and an air and water mixture (adjacent to the BTF) .
  • the height of the air trap fins 410 helps determine the thickness of the water- flow boundary layer. It should be appreciated that the height of the air trap fins 410 can be
  • the air trap fins may be shorter, and for a longer hull the air trap fins may be taller.
  • Air trap fins 410 may run for only a portion of the length of the hull or for the entirety of the length of the hull, and may be radially distributed on all surfaces (Figs. 37A and 37C) .
  • air trap fins 410 may be
  • This configuration can provide better support for the craft, inasmuch as the water beneath (and supporting) the craft is relatively free of air and hence substantially not compressible under the weight of the craft .
  • the marine vessel propeller system comprises a single propeller 415 placed at the bow of a buoyant tubular foil 200.
  • the propeller 415 is sized and configured such that, in operation, the propeller creates and dispenses rearwardly an intense stream of supercavitated water which envelopes the hull of the buoyant tubular foil, which is also preferably provided with air trap fins as previously described, and operative to prevent immediate escape of the supercavitated water from the buoyant tubular foil (BTF) 200.
  • steering may be provided by spoilers as previously disclosed herein or, alternatively, by conventional rudders 420 (and, optionally, planes 425) as shown in Fig. 37E.
  • a novel fleet protection attack craft 5 which generally comprises a command module 100 for carrying crew, weapons and payload (including passengers) , a pair of buoyant tubular foils (BTFs) 200 for providing
  • a novel submersible water craft (which may also sometimes hereinafter be referred to herein as a vehicle or vessel, with the terms craft, vehicle and/or vessel meant to be interchangeable) , such as a submarine and/or a torpedo and/or an
  • unmanned drone, etc. which utilizes a single (buoyant) tubular hull, generally of the sort disclosed above in connection with buoyant tubular foil (BTF) 200, as the hull of the submersible water craft (e.g., submarine, torpedo, unmanned drone, etc.) .
  • buoyant tubular foil BTF
  • such a tubular hull may be considered to be a buoyant tubular foil (BTF) , and may sometimes be so referred to herein.
  • submarine 430 which comprises a tubular hull (i.e., BTF) 435, and front-pulling propeller or propellers 440 for providing propulsion and an air skirt
  • BTF tubular hull
  • front-pulling propeller or propellers 440 for providing propulsion and an air skirt
  • Novel submarine 500 is uniquely suited to rapidly and covertly deploying small teams of personnel to any coastline in the world.
  • submarine 500 generally comprises a tubular hull (i.e., BTF) 505 having a conning tower 510 extending upwards therefrom, and including a pilot cockpit 515, crew quarters 520, an engine room 525, and an area 530 for storing fuel (e.g., in fuel tanks and/or fuel bladders, etc., not shown) and/or other cargo (e.g., weapons).
  • BTF tubular hull
  • conning tower 510 extending upwards therefrom, and including a pilot cockpit 515, crew quarters 520, an engine room 525, and an area 530 for storing fuel (e.g., in fuel tanks and/or fuel bladders, etc., not shown) and/or other cargo (e.g., weapons).
  • fuel e.g., in fuel tanks and/or fuel bladders, etc., not shown
  • other cargo e.g., weapons
  • Submarine 500 also comprises front-pulling propeller or propellers 535 for providing propulsion and an air skirt (supercavitation) for engulfing the hull of the submarine in the manner previously
  • a pair of counter-rotating propellers 535 are used, with the pair of counter-rotating propellers being arranged to cancel out any rotational forces which might induce the submarine to spin on its lengthwise axis.
  • submarine 500 preferably comprises nozzles 545 disposed just aft of propeller (s) 535, and also disposed on the front edges of conning tower 510, for ejecting fluids (e.g., gases and/or low friction liquids) from the submarine and into the flow of water around the submarine, whereby to further reduce friction as the submarine moves through the water.
  • Submarine 500 preferably also comprises a pair of horizontal stabilizers 550 for providing additional attitude control for the submarine, e.g, while the submarine is operating at low speeds.
  • Horizontal stabilizers 550 are preferably retractable into hull 505 for reduced friction when the submarine is running at high speeds .
  • a gas turbine engine 555 aspirated through a telescoping snorkel 560, is provided for high speed propulsion when the submarine is running on the surface of the water or at a depth shallow enough for snorkel 560 to function.
  • An electric motor 565 powered by batteries 570, is provided for propulsion when the submarine is
  • submarine requires "silent" running (e.g., for covert operations) .
  • Ballast tanks (not shown) of the sort well known in the art are provided for regulating the buoyancy of the submarine in the water.
  • An air lock 575 is preferably provided in hull 505 in order to permit divers to exit and enter the hull while the submarine is submerged.
  • an air lock (not shown) may be provided in conning tower 510 for access via top hatch 580. If desired, retractable wheels 585 may be
  • submarine 500 travels through the ocean at high speeds, powered by its gas turbine engine 555, which is aspirated through telescoping snorkel 560. This is preferably done with the submarine operating fully submerged at snorkel depth, although it may also be done with the conning tower 510 protruding above the surface of the water while the hull 505 is submerged below the surface of the water.
  • Front-pulling propeller (s) 535 which provide both propulsion and an air skirt
  • nozzles 545 (disposed just aft of propeller (s) 535, and also disposed on the front edges of conning tower 510) eject fluids (e.g., gases and/or low friction liquids) from the submarine and into the flow of water around the submarine, whereby to further reduce friction as the submarine moves through the water.
  • fluids e.g., gases and/or low friction liquids
  • horizontal stabilizers 550 are preferably retracted into hull 505 for reduced friction.
  • the submarine can submerge below snorkel depth and switch to battery power. While this typically results in limited operating time and/or in slower operating speeds due to the limited onboard battery capacity, it allows the submarine to operate substantially
  • horizontal stabilizers 550 may be used to enhance attitude control.
  • the submarine When the submarine is to approach a shoreline (e.g., to deploy a covert team of personnel), the submarine can operate on battery power so as to minimize noise and avoid detection.
  • Personnel can exit and enter the submarine while the submarine is submerged via air lock 575 and/or top hatch 580.
  • batteries 570 may be replaced by, and/or supplemented by, fuel cells of the sort known in the art .
  • a single tubular structure such as a body 445 of a torpedo 450
  • a warhead e.g., detonator and high explosives
  • buoyancy including negative buoyancy where desired
  • propulsion and steering as is known in the art.
  • buoyancy is preferably provided by ballast tanks contained within the body 445 of the torpedo 450.
  • Propulsion is provided by at least one front- pulling propeller 455 of the sort disclosed above, and an electric motor contained within the body 445 of the torpedo 450, with the front-pulling propeller or propellers 455 providing an air skirt
  • steering may be provided by spoilers as previously disclosed herein or, alternatively, rudders 420 (and, optionally, planes 425) as shown in Fig. 39.
  • Fig. 40 there is shown a novel unmanned submersible craft 600 formed in accordance with the present invention. Novel unmanned
  • submersible craft 600 is uniquely suited to rapidly and covertly enter areas where it is necessary to gather visual, electronic (including radar and sonar) and/or chemical data in order to assess a situation.
  • unmanned submersible craft 600 generally comprises a tubular hull (i.e., BTF) 605 having an equipment area 620, an engine room 625, and an area 630 for storing fuel (e.g., in fuel tanks and/or fuel bladders, etc., not shown) and/or other cargo (e.g., weapons) .
  • BTF tubular hull
  • fuel e.g., in fuel tanks and/or fuel bladders, etc., not shown
  • other cargo e.g., weapons
  • Unmanned submersible craft 600 also comprises front-pulling propeller or propellers 635 for
  • a pair of counter-rotating propellers 635 are used, with the pair of counter-rotating propellers being arranged to cancel out any rotational forces which might induce the submarine to spin on its lengthwise axis.
  • nozzles 645 disposed just aft of propeller(s) 635 for ejecting fluids (e.g., gases and/or low friction liquids) from the unmanned
  • Unmanned submersible craft 600 preferably also comprises a pair of horizontal stabilizers 650 (only one of which is shown in Fig. 40) for providing additional attitude control for the unmanned submersible craft, e.g, while the unmanned submersible craft is operating at low speeds.
  • Horizontal stabilizers 650 are preferably retractable into hull 605 for reduced friction when the unmanned submersible craft is running at high speeds.
  • a gas turbine engine 655 aspirated through a pivotally-retractable or telescoping snorkel 660, is provided for high speed propulsion when the unmanned submersible craft is running on the surface of the water or at a depth shallow enough for snorkel 660 to function.
  • An electric motor 665 powered by batteries 670, is provided for propulsion when the unmanned submersible craft is submerged below snorkel depth and/or when the unmanned submersible craft requires “silent" running (e.g., for covert operations).
  • Ballast tanks (not shown) of the sort well known in the art are provided for regulating the buoyancy of the unmanned submersible craft in the water.
  • unmanned submersible craft 600 be able to gather visual, electronic (including radar and sonar) and/or chemical data in the area around the craft.
  • This typically means gathering visual, electronic and/or chemical data from above the surface of the water, although in some circumstances it may also involve gathering visual, electronic and/or chemical data from below the surface of the water.
  • the visual, electronic and/or chemical data is gathered from above the surface of the water while the unmanned submersible craft remains in a submerged condition so as to minimize the possibility of detection.
  • the visual, electronic and/or chemical sensors are preferably adapted to be advanced from the
  • unmanned submersible craft to a position above the surface of the water while the unmanned submersible craft remains below the surface of the water. This may be done by mounting visual, electronic and/or chemical sensors to snorkel 660 so that visual, electronic and/or chemical sensors project above the surface of the water while snorkel 660 is in its deployed condition. Additionally, visual, electronic and/or chemical sensors may be mounted to a
  • visual, electronic and/or chemical sensors may be raised to the surface of the water while the unmanned submersible craft remains below the surface of the water.
  • visual, electronic and/or chemical sensors may be mounted in nose cone 680, and/or tail cone 685, so that visual, electronic and/or chemical data can be gathered by the unmanned submersible craft.
  • submersible craft 600 travels through the ocean at high speeds, powered by its gas turbine engine 655, which is aspirated through telescoping snorkel 660. This is done with the unmanned submersible craft operating fully submerged at snorkel depth.
  • Front- pulling propeller (s) 635 which provide both
  • nozzles 645 disposed just aft of propeller(s) 635) eject fluids (e.g., gases and/or low friction liquids) from the unmanned submersible craft and into the flow of water around the unmanned
  • horizontal stabilizers 650 are preferably retracted into hull 605 for reduced friction.
  • the unmanned submersible craft 600 can submerge below snorkel depth and switch to battery power. While this typically results in limited operating time and/or in slower operating speeds due to the limited onboard battery capacity, it allows the unmanned submersible craft to operate substantially silently.
  • horizontal stabilizers 650 may be used to enhance attitude control .
  • the unmanned submersible craft may be carried by an aircraft to an area closer to its final destination, and then dropped from the aircraft, so as to shorten the distance to be traveled by the unmanned submersible craft and still maintain its stealth approach.
  • the unmanned submersible craft When the unmanned submersible craft has reached the area in which it is to gather visual, electronic and/or chemical data, it preferably remains submerged and runs under battery power, except for short periods of time when it may rise to snorkel depth and run under its gas turbine engine 655 so as to recharge its batteries. With the unmanned submersible craft remaining submerged, visual, electronic and/or chemical data is gathered by the sensors carried by the craft, e.g., from above the surface of the water by raising sensors to the surface by a telescoping mast (not shown) or a floating buoy (not shown) projected from deployment chamber 675, and/or from below the surface of the water via the sensors carried by nose cone 680 and/or tail cone 685.
  • the sensors carried by the craft e.g., from above the surface of the water by raising sensors to the surface by a telescoping mast (not shown) or a floating buoy (not shown) projected from deployment chamber 675, and/or from below the surface of the water via the sensors carried by nose cone 680
  • the unmanned submersible craft may reposition itself into a
  • tail cone 685 projects above the surface of the water, such that the sensors in tail cone 685 may be used to acquire visual, electronic and/or chemical data from above the surface of the water.
  • the data acquired by the unmanned submersible craft may then be transmitted back to a base station by conventional radio transmission of the sort well known in the art .
  • batteries 670 may be replaced by, and/or supplemented by, fuel cells of the sort known in the art .
  • nose cone 680, and/or tail cone 685, and/or hull 605 may carry fittings for
  • a fuel source e.g., a surface vessel, a
  • propeller mechanism is used to both (i) pull the buoyant tubular foil (BTF) 200 (or other tubular structure) though the water, and (ii) generate the friction-reducing air curtain which engulfs the trailing BTF 200 (or other tubular structure) .
  • BTF buoyant tubular foil
  • the same element i.e., the front pulling propeller mechanism
  • the front pulling propeller mechanism is used to simultaneously provide both propulsion and the supercavitating friction-reducing air curtain.
  • each of these aspects provides significant improvements in propulsion efficiencies, with (i) the front pulling propeller mechanism biting into virgin water, which enhances the propulsion action of the propeller mechanism, and (ii) the front pulling propeller mechanism providing the supercavitating friction-reducing air curtain which reduces hull friction as the BTF 200 (or other tubular structure) moves through the water.
  • the front pulling propeller mechanism is used to
  • BTF 200 (or other tubular structure) is part of a SWATH surface vessel, or is the hull of a submarine or other submersible vessel, or is the fuselage of another form of submersible vehicle such as a torpedo or unmanned drone.
  • BTF 200 or other tubular structure
  • the front pulling propeller mechanism simultaneously provides its dual function (i.e., propulsion and the supercavitating friction-reducing air curtain) for the elongated hull structure (i.e., the BTF 200 or other tubular structure) which trails the front pulling propeller mechanism.
  • the elongated hull structure i.e., the BTF 200 or other tubular structure
  • the front pulling propeller mechanism simultaneously provides its dual function (i.e., propulsion and the supercavitating friction-reducing air curtain) for the elongated hull structure (i.e., the BTF 200 or other tubular structure) which trails the front pulling propeller mechanism.
  • the elongated hull structure i.e., the BTF 200 or other tubular structure
  • the front pulling propeller mechanism be configured (e.g., blade shape, blade size, number of blades employed, counterrotation of the blades if more than one blade is provided, etc.) and operated (e.g., blade rotation speed, etc.) for both efficient propulsion and efficient air curtain generation.
  • the propeller mechanism should generate an air curtain of sufficient size and volume to engulf all (or substantially all) of the perimeter of the trailing hull structure (e.g., the BTF 200) .
  • not all front pulling propeller mechanisms will generate the supercavitating friction-reducing air curtain desired in the present invention.
  • a propeller rotating relatively slowly will generate minimal
  • supercavitation function (which may be a desired design feature, such as on a ballistic missile
  • a relatively small propeller may throw off a bubble stream, but the bubble stream may not be large enough to engulf the perimeter of the trailing hull structure and thereby provide the desired air curtain about the outer surface of the trailing hull structure.
  • the configuration of the front pulling propeller mechanism e.g., blade shape, blade size, number of blades employed, counterrotation of the blades if more than one blade is provided, etc.
  • the operation of the front pulling propeller mechanism e.g., blade rotation speed, etc.
  • the front pulling propeller mechanism comprises a pair of counterrotating propellers to efficiently provide both propulsion and the supercavitating friction-reducing air curtain, with the propellers having a diameter which is approximately 33 percent to approximately 90 percent of the diameter of the trailing BTF, and most preferably approximately 66 percent of the diameter of the trailing BTF 200 (or other tubular structure) , and a rotation speed of approximately 2000 to
  • attack craft 5 is described in the context of its use for military applications. However, it should be appreciated that attack craft 5 may also be used for other, non- military applications such as security applications (e.g., police, immigration and drug enforcement purposes), public safety applications (e.g., sea rescues) , high-speed servicing and re-supply
  • security applications e.g., police, immigration and drug enforcement purposes
  • public safety applications e.g., sea rescues

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Ocean & Marine Engineering (AREA)
  • Aviation & Aerospace Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • General Engineering & Computer Science (AREA)
  • Other Liquid Machine Or Engine Such As Wave Power Use (AREA)
  • Toys (AREA)
PCT/US2012/031607 2011-03-30 2012-03-30 High speed surface craft and submersible vehicle WO2012135718A1 (en)

Priority Applications (6)

Application Number Priority Date Filing Date Title
CA2831921A CA2831921A1 (en) 2011-03-30 2012-03-30 High speed surface craft and submersible vehicle
JP2014502861A JP2014512300A (ja) 2011-03-30 2012-03-30 高速水上艇および潜水航行体
EP12763732.0A EP2691290A4 (en) 2011-03-30 2012-03-30 SURFACE BOATING AND SUBMERSIBLE HIGH SPEED VEHICLE
AU2012236188A AU2012236188B2 (en) 2011-03-30 2012-03-30 High speed surface craft and submersible vehicle
KR1020137028795A KR20140079746A (ko) 2011-03-30 2012-03-30 고속 수상 크래프트 및 잠수 비클
IL228628A IL228628A0 (en) 2011-03-30 2013-11-14 A vessel for fast movement on the surface of the water and for diving

Applications Claiming Priority (8)

Application Number Priority Date Filing Date Title
US201161469143P 2011-03-30 2011-03-30
US201161469127P 2011-03-30 2011-03-30
US61/469,143 2011-03-30
US61/469,127 2011-03-30
US13/212,767 US8857365B2 (en) 2008-06-16 2011-08-18 Fleet protection attack craft and underwater vehicles
US13/212,767 2011-08-18
PCT/US2011/052642 WO2013043171A2 (en) 2011-09-21 2011-09-21 Fleet protection attack craft and submersible vehicle
USPCT/US2011/052642 2011-09-21

Publications (1)

Publication Number Publication Date
WO2012135718A1 true WO2012135718A1 (en) 2012-10-04

Family

ID=46931956

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2012/031607 WO2012135718A1 (en) 2011-03-30 2012-03-30 High speed surface craft and submersible vehicle

Country Status (8)

Country Link
US (2) US8683937B2 (ko)
EP (1) EP2691290A4 (ko)
JP (2) JP2014512300A (ko)
KR (1) KR20140079746A (ko)
AU (1) AU2012236188B2 (ko)
CA (1) CA2831921A1 (ko)
IL (1) IL228628A0 (ko)
WO (1) WO2012135718A1 (ko)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20150121997A (ko) * 2014-04-22 2015-10-30 대우조선해양 주식회사 마스트 모듈을 포함하는 함교 구조물 및 이를 적용한 잠수함
ES2570079A1 (es) * 2014-11-13 2016-05-13 Advance Intelligent Developments S.L. Embarcación convertible
CN105620652A (zh) * 2016-03-01 2016-06-01 哈尔滨工程大学 机动控制和阻滞气体泄漏的可收缩空化器结构和一种多级可伸缩空化器
CN106364624A (zh) * 2016-10-27 2017-02-01 中国运载火箭技术研究院 一种应用于航行体自主稳定航行的控制装置及方法
EP3019396A4 (en) * 2013-07-10 2017-03-15 Juliet Marine Systems, Inc. High speed surface craft and submersible craft
CN107054596A (zh) * 2016-09-19 2017-08-18 管理 一种双椭球冠螺旋桨对称前置的潜艇舰船超空泡技术
US9783275B2 (en) 2008-06-16 2017-10-10 Juliet Marine Systems, Inc. High speed surface craft and submersible craft
CN110027669A (zh) * 2019-05-09 2019-07-19 哈尔滨工程大学 一种用于超空泡水面艇的通气减阻支柱结构
CN110758695A (zh) * 2019-11-27 2020-02-07 中国人民解放军国防科技大学 一种自适应连续可调的空化器结构

Families Citing this family (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8857365B2 (en) 2008-06-16 2014-10-14 Juliet Marine Systems, Inc. Fleet protection attack craft and underwater vehicles
US9168978B2 (en) 2008-06-16 2015-10-27 Juliet Marine Systems, Inc. High speed surface craft and submersible craft
CA2831921A1 (en) * 2011-03-30 2012-10-04 Juliet Marine Systems, Inc. High speed surface craft and submersible vehicle
US9032900B2 (en) * 2012-04-25 2015-05-19 Georgia Tech Research Corporation Marine vehicle systems and methods
IL228688B (en) * 2013-10-02 2018-05-31 Elta Systems Ltd Mast system and method for operating a mast system
JP2015196410A (ja) * 2014-03-31 2015-11-09 ヤンマー株式会社 燃料電池船
WO2015151983A1 (ja) * 2014-03-31 2015-10-08 ヤンマー株式会社 燃料電池船
CN103926051B (zh) * 2014-05-06 2016-07-06 中国船舶重工集团公司第七○二研究所 带有内置舵机装置的超空泡航行体模型
CN105711733B (zh) * 2016-03-21 2018-01-23 刘石全 船用浮筒的制造方法
WO2018016863A1 (ko) * 2016-07-19 2018-01-25 현대중공업 주식회사 마찰저감장치 및 이를 포함하는 선박
CN106184665B (zh) * 2016-08-16 2018-08-24 武汉工程大学 一种潜艇的被动防护方法
CN109383206B (zh) * 2017-08-10 2021-10-22 益阳天华两栖车艇有限公司 一种折叠式滑水板装置
WO2019106683A1 (en) * 2017-11-28 2019-06-06 Maria Ivan John Apparatus for improving acceleration, stability, safety, maneuverability and deceleration of water crafts
RU2694670C1 (ru) * 2018-12-13 2019-07-16 Михаил Алексеевич Макаров Многофункциональный вездеход
CN109987207B (zh) * 2019-04-24 2024-01-12 合肥天鹅制冷科技有限公司 一种基于plc控制系统的舰船潜水舱环控装置
CN110274750B (zh) * 2019-07-25 2020-10-30 哈尔滨工业大学 一种带有弹性尾缘的超空泡航行体试验模型
CN110723270B (zh) * 2019-10-10 2022-07-12 上海交通大学 一种大尺度刚柔一体结构的平流层飞艇
CN113844631A (zh) * 2020-06-28 2021-12-28 广州极飞科技股份有限公司 无人船的动力装置、船体和无人船
CN111942551A (zh) * 2020-09-07 2020-11-17 北京大学 基于仿生两栖型机器人的水下空气润滑辅助推进器
CN112319750B (zh) * 2020-11-05 2021-08-13 广州黄船海洋工程有限公司 一种饱和潜水系统应急逃生系统
CN112440634B (zh) * 2020-11-12 2022-08-23 内蒙古第一机械集团股份有限公司 一种适用于两栖车的整流装置
JP7114119B1 (ja) * 2021-04-01 2022-08-08 株式会社タジマモーターコーポレーション 水素タンク船舶

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2823636A (en) * 1955-02-13 1958-02-18 Aerojet General Co Vessel
US3683622A (en) * 1968-10-09 1972-08-15 Asea Ab Method of supplying a propulsion device with fuel
US3987742A (en) * 1974-03-19 1976-10-26 Etat Francais Represente Par Le Deleque Ministeriel Pour L'armement Swivel air lock for airtight connection between submergibles
US4186679A (en) * 1965-03-17 1980-02-05 The United States Of America As Represented By The Secretary Of The Navy Torpedo drag reduction employing polymer ejection
US20020152947A1 (en) * 1999-11-24 2002-10-24 Hilleman Terry B. Bow mounted system and method for jet-propelling a submarine or torpedo through water
US20040200399A1 (en) * 2003-04-11 2004-10-14 Moustafa Abdel-Maksoud Method and apparatus for enhancing the internal combustion engine performance for submarines in snorkel running
US20080132130A1 (en) * 2004-06-07 2008-06-05 Thales Holding Uk Plc Buoyant Device

Family Cites Families (73)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3016865A (en) 1959-05-21 1962-01-16 Thompson Ramo Wooldridge Inc Method and apparatus for reducing drag on submerged vehicles
US3106179A (en) 1961-12-11 1963-10-08 Lockheed Aircraft Corp Propulsion system for a hydrofoil vessel
US3163980A (en) 1963-01-23 1965-01-05 James J Turner Water jet propulsion
US3343513A (en) 1966-05-27 1967-09-26 Bader John Hydrofoils and retraction mechanism therefor
US3411301A (en) 1966-07-15 1968-11-19 Douglas R. Olsen Thermal hydrojet
US3430595A (en) 1967-02-20 1969-03-04 Harry Werner Tulleners Watercraft
US3779199A (en) 1969-09-25 1973-12-18 R Mayer Boundary layer control means
US3678872A (en) * 1970-09-14 1972-07-25 Luigi Migliaccio Emergency underwater escape vehicle
US3730123A (en) 1971-11-18 1973-05-01 T Lang High speed ship with submerged hull
GB1413845A (en) 1972-02-11 1975-11-12 Rolls Royce Marine propulsion
US3830178A (en) 1973-04-26 1974-08-20 Us Navy Semisubmerged ship with hull extensions
US4346662A (en) 1980-05-07 1982-08-31 The United States Of America As Represented By The Secretary Of The Navy Self-contained backflush/start system for suction LFC undersea vehicle
JPS5768481U (ko) * 1980-10-14 1982-04-24
US4546721A (en) * 1983-05-05 1985-10-15 Mobil Oil Corporation Submerged single point mooring system
JPS59213592A (ja) * 1983-05-17 1984-12-03 Mitsubishi Heavy Ind Ltd 抵抗用フイン制御式水中航走体
US4681508A (en) 1984-11-14 1987-07-21 Kim Choong W Supercavitation centrifugal pump
US4902254A (en) 1985-09-05 1990-02-20 Chas Jean Bernard Propulsion device with conditioned inertia
JPS62119000U (ko) * 1986-01-13 1987-07-28
US4680017A (en) 1986-03-10 1987-07-14 Eller Dennis E Motorboat propeller guard for improved performance
DE3614291A1 (de) 1986-04-26 1987-10-29 Peter Labentz Wasserfahrzeug
JPS63193997U (ko) * 1987-05-30 1988-12-14
US4819576A (en) 1988-01-20 1989-04-11 Shaw Chung Chen C Hydrofoil - submarine vessel system
US4831297A (en) 1988-02-16 1989-05-16 Westinghouse Electric Corp. Submersible electric propulsion motor with propeller integrated concentrically with motor rotor
US4981099A (en) 1988-03-17 1991-01-01 Ron Holder Watercraft
US4962718A (en) 1988-04-27 1990-10-16 Westfoil International Hydrofoil propulsion system
JPH03125694A (ja) * 1989-10-12 1991-05-29 Ishikawajima Harima Heavy Ind Co Ltd 外周型推進装置
US5252875A (en) 1990-08-23 1993-10-12 Westinghouse Electric Corp. Integral motor propulsor unit for water vehicles with plural electric motors driving a single propeller
FR2671048A1 (fr) 1991-01-02 1992-07-03 Jean Bernard Chas Propulseur attele dans son jet creux.
US5279247A (en) * 1991-06-28 1994-01-18 The United States Of America As Represented By The Secretary Of The Navy Submarine mast fairing bearing configuration
US5277142A (en) 1991-11-01 1994-01-11 Connor Dennis P Variable-beam catamaran
US5191848A (en) 1991-12-11 1993-03-09 Gold Coast Yachts, Inc. Multihull vessels, including catamarans, with wave piercing hull configuration
US5237947A (en) 1992-08-03 1993-08-24 The United States Of America As Represented By The Secretary Of The Navy Variable draft hull
US5301624A (en) 1993-02-24 1994-04-12 Swath Ocean Systems, Inc. Stern planes for swath vessel
US5355827A (en) 1993-05-28 1994-10-18 Dcd, Ltd. Catamaran
US5645008A (en) 1993-12-01 1997-07-08 Pacific Marine Supply Co., Ltd. Mid foil SWAS
US5794558A (en) 1993-12-01 1998-08-18 Pacific Marine Supply Co., Ltd. Mid foil SWAS
US5359958A (en) 1994-05-06 1994-11-01 Guild Johnithan R High-speed watercraft
US5503100A (en) 1994-05-09 1996-04-02 Shaw; Clifford C. C. Hybrid water vessels
US5813358A (en) 1994-06-24 1998-09-29 Roccotelli; Sabino Surface-piercing surface effect marine craft
US5598700A (en) 1994-06-30 1997-02-04 Dimotech Ltd. Underwater two phase ramjet engine
US5941189A (en) 1995-01-13 1999-08-24 Johansson; Nils Erik Watercraft
US5551369A (en) 1995-03-31 1996-09-03 The United States Of America As Represented By The Secretary Of The Navy Dualcavitating hydrofoil structures
US5601047A (en) 1995-03-31 1997-02-11 The United States Of America As Represented By The Secretary Of The Navy Dualcavitating hydrofoil structures for multi-speed applications
US5511504A (en) 1995-08-09 1996-04-30 Martin; John R. Computer controlled fins for improving seakeeping in marine vessels
US5632658A (en) 1996-05-21 1997-05-27 The United States Of America As Represented By The Secretary Of The Navy Tractor podded propulsor for surface ships
US5634419A (en) 1996-06-26 1997-06-03 Cymara; Hermann K. Front-drive boat
WO1998008732A1 (en) 1996-08-27 1998-03-05 Newport Technologies, Ltd. Hydroskiing marine vessel
US6095076A (en) 1998-10-14 2000-08-01 Nesbitt; Glenn Scott Hydrofoil boat
US6058872A (en) 1998-10-22 2000-05-09 Board Of Supervisors Of Louisiana State University And Agricultural And Mechanical College Hybrid hull for high speed water transport
US6470817B2 (en) 1999-03-01 2002-10-29 Barry E. Delfosse Small waterplane area multihull (SWAMH) vessel
US6427618B1 (en) 1999-11-24 2002-08-06 Terry B. Hilleman Bow mounted system and method for jet-propelling a submarine or torpedo through water
US6725797B2 (en) 1999-11-24 2004-04-27 Terry B. Hilleman Method and apparatus for propelling a surface ship through water
JP3995855B2 (ja) * 2000-01-20 2007-10-24 カヤバ システム マシナリー株式会社 長尺浮遊物の揚収方法および揚収装置
JP4435932B2 (ja) * 2000-04-18 2010-03-24 三菱重工業株式会社 水中航走体用の通信システム、および、そのための自走中継器
JP2001349272A (ja) * 2000-06-07 2001-12-21 Chuzaburo Ichiyoshi 洋上風力発電システム
US6591776B2 (en) 2001-11-14 2003-07-15 Kunio Miyazaki Semi-submergence type hydrofoil craft
US6789490B2 (en) 2002-02-19 2004-09-14 Lockheed Martin Corporation Ship constructions for achieving stability at high speed through the use of multiple, low wave-making resistance, submerged hullform pods and control fins
US6761331B2 (en) 2002-03-19 2004-07-13 Raytheon Company Missile having deployment mechanism for stowable fins
JP4401293B2 (ja) 2002-08-14 2010-01-20 ヘイリング テクノロジーズ ピーティーワイ リミテッド 船舶
US6651433B1 (en) * 2002-09-13 2003-11-25 Leslie C. George, Jr. Brayton screw engine with brayton bottoming system
JP2005096497A (ja) * 2003-09-22 2005-04-14 Mitsubishi Heavy Ind Ltd 水中航走体
ITGE20040013A1 (it) 2004-02-24 2004-05-24 Giorgio Brighi Appendici di carena retrattili per il governo e per la stabilizzazione di natanti a motore.
WO2006083261A2 (en) 2004-04-30 2006-08-10 Lockheed Martin Corporation Reconfigurable attack and reconnaissance vessel i
DE102004024972A1 (de) * 2004-05-21 2005-12-15 Howaldtswerke-Deutsche Werft Gmbh Verfahren zur Fahrtplanung eines Unterseebootes
US7225748B2 (en) 2004-12-31 2007-06-05 Mga Entertainment Stealthy powered catamaran
JP4616662B2 (ja) * 2005-02-17 2011-01-19 三菱重工業株式会社 水中航走体及びその制御方法
FR2883547B1 (fr) 2005-03-25 2007-06-08 Frederic Jouffroy Dispositif amovible a flotteurs repliables pour transformer une embarcation monocoque en une embarcation multicoque et embarcation le comportant
FR2887224B1 (fr) * 2005-06-16 2008-10-17 Julien Apeloig Engin multimilieux
US7096810B1 (en) * 2005-09-20 2006-08-29 Adams Robert D Bow mounted vessel propulsion system
JP2007276609A (ja) * 2006-04-06 2007-10-25 Osaka Prefecture Univ 水中グライダー
GB2456179B (en) * 2008-01-07 2012-02-15 Converteam Technology Ltd Marine power distribution and propulsion systems
US8857365B2 (en) * 2008-06-16 2014-10-14 Juliet Marine Systems, Inc. Fleet protection attack craft and underwater vehicles
CA2831921A1 (en) * 2011-03-30 2012-10-04 Juliet Marine Systems, Inc. High speed surface craft and submersible vehicle

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2823636A (en) * 1955-02-13 1958-02-18 Aerojet General Co Vessel
US4186679A (en) * 1965-03-17 1980-02-05 The United States Of America As Represented By The Secretary Of The Navy Torpedo drag reduction employing polymer ejection
US3683622A (en) * 1968-10-09 1972-08-15 Asea Ab Method of supplying a propulsion device with fuel
US3987742A (en) * 1974-03-19 1976-10-26 Etat Francais Represente Par Le Deleque Ministeriel Pour L'armement Swivel air lock for airtight connection between submergibles
US20020152947A1 (en) * 1999-11-24 2002-10-24 Hilleman Terry B. Bow mounted system and method for jet-propelling a submarine or torpedo through water
US20040200399A1 (en) * 2003-04-11 2004-10-14 Moustafa Abdel-Maksoud Method and apparatus for enhancing the internal combustion engine performance for submarines in snorkel running
US20080132130A1 (en) * 2004-06-07 2008-06-05 Thales Holding Uk Plc Buoyant Device

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See also references of EP2691290A4 *

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9783275B2 (en) 2008-06-16 2017-10-10 Juliet Marine Systems, Inc. High speed surface craft and submersible craft
US10730597B2 (en) 2008-06-16 2020-08-04 Juliet Marine Systems, Inc. High speed surface craft and submersible craft
EP3019396A4 (en) * 2013-07-10 2017-03-15 Juliet Marine Systems, Inc. High speed surface craft and submersible craft
KR20150121997A (ko) * 2014-04-22 2015-10-30 대우조선해양 주식회사 마스트 모듈을 포함하는 함교 구조물 및 이를 적용한 잠수함
KR101596129B1 (ko) * 2014-04-22 2016-02-19 대우조선해양 주식회사 마스트 모듈을 포함하는 함교 구조물 및 이를 적용한 잠수함
ES2570079A1 (es) * 2014-11-13 2016-05-13 Advance Intelligent Developments S.L. Embarcación convertible
CN105620652A (zh) * 2016-03-01 2016-06-01 哈尔滨工程大学 机动控制和阻滞气体泄漏的可收缩空化器结构和一种多级可伸缩空化器
CN107054596A (zh) * 2016-09-19 2017-08-18 管理 一种双椭球冠螺旋桨对称前置的潜艇舰船超空泡技术
CN106364624A (zh) * 2016-10-27 2017-02-01 中国运载火箭技术研究院 一种应用于航行体自主稳定航行的控制装置及方法
CN110027669A (zh) * 2019-05-09 2019-07-19 哈尔滨工程大学 一种用于超空泡水面艇的通气减阻支柱结构
CN110758695A (zh) * 2019-11-27 2020-02-07 中国人民解放军国防科技大学 一种自适应连续可调的空化器结构
CN110758695B (zh) * 2019-11-27 2020-09-18 中国人民解放军国防科技大学 一种自适应连续可调的空化器结构

Also Published As

Publication number Publication date
IL228628A0 (en) 2013-12-31
KR20140079746A (ko) 2014-06-27
EP2691290A4 (en) 2015-09-09
AU2012236188A1 (en) 2013-11-14
US8683937B2 (en) 2014-04-01
US9592894B2 (en) 2017-03-14
EP2691290A1 (en) 2014-02-05
AU2012236188B2 (en) 2016-10-20
US20150068441A1 (en) 2015-03-12
CA2831921A1 (en) 2012-10-04
JP2014512300A (ja) 2014-05-22
US20120315811A1 (en) 2012-12-13
JP2017197182A (ja) 2017-11-02

Similar Documents

Publication Publication Date Title
US10730597B2 (en) High speed surface craft and submersible craft
US9592894B2 (en) High speed surface craft and submersible vehicle
US9555859B2 (en) Fleet protection attack craft and underwater vehicles
US9403579B2 (en) Fleet protection attack craft
US9168978B2 (en) High speed surface craft and submersible craft
US9663212B2 (en) High speed surface craft and submersible vehicle
US5713293A (en) Unmanned sea surface vehicle having a personal watercraft hull form
US3236202A (en) Water craft
US7278364B2 (en) Reconfigurable attack and reconnaissance vessel I
EP3019396A2 (en) High speed surface craft and submersible craft
FR2688466A1 (fr) Embarcation militaire pour harcelement de grosses unites navales.
WO2013043171A2 (en) Fleet protection attack craft and submersible vehicle
US3250238A (en) Transportable observation station
CN1333163A (zh) 不用注排压载水就可快速升潜的潜水船
RU2389639C2 (ru) Патрульный комплекс
CN106516053A (zh) 一种微型潜艇的外挂仓
CN106741768A (zh) 微型潜艇外挂仓分离装置
FR3018262A1 (fr) Vehicule d'embarcation hybride submersible semi rigide
CN118289189A (zh) 水面-水下两栖可滑行变水深带载隐身无人艇
August Sentinel-Like UUV Design Concepts for Coastal Defense

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 12763732

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2014502861

Country of ref document: JP

Kind code of ref document: A

Ref document number: 2831921

Country of ref document: CA

NENP Non-entry into the national phase

Ref country code: DE

WWE Wipo information: entry into national phase

Ref document number: 2012763732

Country of ref document: EP

ENP Entry into the national phase

Ref document number: 20137028795

Country of ref document: KR

Kind code of ref document: A

ENP Entry into the national phase

Ref document number: 2012236188

Country of ref document: AU

Date of ref document: 20120330

Kind code of ref document: A