HYDROFOILS

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HYDROFOILS HOVERCRAFTS
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WHO KNOWS WHAT A HYDROFOIL IS?
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WHAT IS A HYDROFOIL ?

• A Foil is another word for a wing.
• A Hydrofoil is simply a wing that flies in the
  water.
• Hydrofoils let a boat go faster by getting the
  hull out of the water.

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HISTORY OF A HYDORFOIL

• The first Hydrofoil vessel was built in 1905 by
  the Italian engineer Enrico Forlanini.
• In 1918, Alexander Graham Bell built the HD-4, a
  hydrofoil vessel 60 ft long which attained a
  speed of 70.86 mph.

BELL HD-4
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HOW DOES IT WORK?

• When a boat moves forward, most of the energy
  used goes to moving the water out of the way.
• The Hydrofoils special design lifts the hull of
  the boat out of the water to reduce the drag,
  which increases speed and fuel efficiency.

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HOW DOES IT WORK?
                                                                           
Detail of Pressure At Points Over An Airfoil

• Hydrofoils lift the watercraft the same way that
  airplane wings keep the plane supported.
• Foils create lift when the water traveling over
  the top goes faster than the water traveling over
  the bottom
• Where there is faster velocity, there is lower
  pressure.

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HOW DOES IT WORK?

• The higher pressure on the bottom of the foil
  causes the lifting force needed.
• The lift can be optimized by positioning the
  hydrofoil at an angle (angle of attack).

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Detail of Hydrofoil a) Pressure Profile    b) Momentum Transfer    c) Circulation     d) Streamlines
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COMMERCIAL USES

• Cargo Vessels
• Passenger Vessels
• Military Vessels

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RECREATIONAL USES

• Sailing
• Wakeboarding
• Air Chairs

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WHO KNOWS WHAT A HOVERCRAFT IS?
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WHAT IS A HOVERCRAFT?

• A Hovercraft is a vehicle supported on a cushion
  of air supplied by a powered fan mounted on the
  back of the vehicle.
• AKA Air Cushion Vehicle (ACV).

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HOW DOES A HOVERCRAFT WORK?

• A Hovercraft is powered by a motor, which drives
  a fan.
• The bigger the vessel the bigger the motor and
  fan needed.
• The fan creates the thrust to drive the
  Hovercraft forward

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HOW DOES A HOVERCRAFT WORK?

• Part of the fan thrust is ducted through the hull
  to lift the craft off the surface on a cushion of
  air.
• The air is held under the craft by a flexible
  skirt which keeps the air cushion pressure up.

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HISTORY OF THE HOVERCRAFT

• The first recorded design for an air cushion
  vehicle was put forward by Swedish designer and
  philosopher, Emmanual Swedenborg in 1716.

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HISTORY OF THE HOVERCRAFT

• The first hovercraft was built by Christopher
  Cockerell in 1956.

SRN1
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HISTORY OF THE HOVERCRAFT

• The theory behind the Hovercraft was originally
  tested in 1955 using an empty cat food tin inside
  a coffee tin, an industrial air blower and a pair
  of kitchen scales.

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WHAT IS SO SPECIAL ABOUT A HOVERCRAFT?

• What makes a Hovercraft so unique is the fact
  that it can travel over any surface, as long as
  it is relatively smooth.
• EX Water, Grass, Ice and Snow.

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WHAT IS SO SPECIAL ABOUT HOVERCRAFTS?

• Hovercrafts can be used year round due to their
  unique design.
• They are used for
• Sports
• Recreation
• Utility/Commercial
• Rescue Purposes

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SPORTS / RECREATIONAL USES

• Cruising
• Hunting
• Fishing
• Touring

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COMMERCIAL USES

• Hovercrafts are mainly used as icebreakers,
  ferrying crafts and hauling vehicles.

• Its primary use of
• commercial hovercrafts is hauling. It is
  sometimes used instead of barges or ocean line
  due to maneuverability and versatility

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RESCUE USES

• The versatility of the Hovercraft allows it to be
  used in most rescue operations
• Flooded areas, mud, ice, sandbars, swamps and
  other dangerous surfaces

Hoverguard 1000
Hoverguard 700
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ANY QUESTIONS?