Alternate Propulsion System for

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Alternate Propulsion System for Air Cushioned
Vehicles (APROPS) First Semester Project
Proposal Group 4 Michelle Aranowski Regina
Forstell Elochukwu Obimdike Sean F.
Pedrizetti Anthony T. Piccolo
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• Objective
• to develop an alternate propulsion system
  (APROPS) to replace the current air screw system
  that is currently employed on the US Navy Landing
  Craft Air Cushion (LCAC)
• the application of a new propulsion system for
  the Joint Surface Assault Connector (JSAC), which
  is currently in development as a replacement to
  the LCAC

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Technical Background

• ACV or Hover Crafts were first developed in
  Britain in 1959
• Developed for the military as ship-to-shore
  transports
• The unique amphibious qualities of the ACV enable
  it to land on 70 of the worlds shore line
• The US currently has had a fleet of Landing Craft
  Air Cushion (LCAC) for the past 20 years

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Current Air Screw System Limitations

• High Power Requirements
• weight of the ACV and payload
• size of Air Screw

• Structural Vibrations
• obstruction of the air flow path
• obstructed mainly by cargo

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Joint Surface Assault Connector (JSAC)

• The US military is currently looking for a new
  ship-to-shore amphibious transport vehicle
• The will replace the LCAC that is currently in
  operation
• The JSAC will be required to carry a larger
  payload than previous ACV
• A new propulsion system is needed

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Function Flow Diagram

• Assumption vehicle starts on ship
• 1. Getting off Ship
• 1a Prep Craft
• loading Crew/Payload
• starting Primary Engines
• power up controls
• unplugging from ship
• starting on-ship propulsion system
• 1b Move off Ship
• exit the ship in reverse

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Function Flow Diagram

• 2. Ship to Surf Zone
• 2a Switch to over water propulsion
• disengage on-ship propulsion system
• engage over water propulsion system
• 2b Move over Water
• maintain speed in specified conditions
• maintain maneuverability

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Function Flow Diagram

• 3. Over Surf Zone
• 3a Switch to Surf Zone propulsion
• disengage over water propulsion system
• engage surf zone propulsion system
• 3b Move over off shore bar
• get to Bar
• negotiate obstacles
• mover past Bar
• 3c Move through Surf Zone
• get to surf zone
• compensate for increased wave height
• maintain maneuverability

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Function Flow Diagram

• 4. Beach Landing
• 4a Switch to over land propulsion
• disengage surf zone propulsion system
• engage over land propulsion system
• 4b Move up beach
• 8 slope
• over range of terrain requirements
• maintain landing speed
• maintain maneuverability
• 4c Move over land to Landing Zone
• negotiate obstacles
• maintain landing speed
• maintain maneuverability
• stop at Landing Zone
• unload Payload
• check vehicle for return trip

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Requirements Weight and Size

• Weight and Payload 224.5 long tons
• Including 89.3 long tons payload
• Craft Dimensions
• Cargo deck requirements

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Requirements Performance over water and land

• Range
• 50 to 100 nautical mile over water
• 1 mile over land
• Speed
• 40 knots over water
• 10 knots over land
• Over Water Conditions
• Over Land Terrain
• mud flats, marsh, dry sand, and wet sand
• 8 slope

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Approach

• Develop of either a hybrid propulsion system or a
  standalone propulsion system
• Hybrid Propulsion system
• Dual Propulsion system
• Separate over water system
• Separate over land system
• Standalone propulsion system
• Dual functioning system for over land and water

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Approach and Trade-off analyses

• Brain Storm propulsion systems
• Run trade-off analyses for Hybrid system
• Run trade-off analyses for Standalone systems
  Including high scoring Hybrid system
• Trade off parameters
• Maneuverability, Effectiveness, Transition,
  External Force Effect, Weight, Power, Size,
  Maintenance, Life cycle, Deck arrangements, Well
  deck storage, Cost, Noise/Vibration, Technology
  risk, Ease of acquisition, and Manufacturability

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Conceptual Design

• Standalone
• Jet Turbine
• Water Wheel
• Archimedes Screw
• Air Screw
• Strictly Land
• Wheels
• Tracks
• Winches w/ Grappling Hook
• Rollagons
• Strictly Water
• Water Screw
• Water Jet

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Project Breakdown Structure
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Questions?