Post on 07-Apr-2018
8/4/2019 27507856 Hovercraft Presentation
http://slidepdf.com/reader/full/27507856-hovercraft-presentation 1/19
Presentation on
HOVERCRAFTS
8/4/2019 27507856 Hovercraft Presentation
http://slidepdf.com/reader/full/27507856-hovercraft-presentation 2/19
Contents
Introduction
History Design
Working
Parts
Piloting a Hovercraft
Conclusion
8/4/2019 27507856 Hovercraft Presentation
http://slidepdf.com/reader/full/27507856-hovercraft-presentation 3/19
Introduction
An amphibious military or civilian vehicle
Travels on any kind of surface (flat)
Supported by a cushion of pressurized air
It is closely related to aircrafts then
automobiles or boats
Also called Air Cushion Vehicle (ACV)
8/4/2019 27507856 Hovercraft Presentation
http://slidepdf.com/reader/full/27507856-hovercraft-presentation 4/19
History
1716 Emmanual Swedenborg recorded a
design, but was short lived
1870 Sir John Thornycroft filled patentsinvolving air lubricated hulls
Christopher Cockrell began experimenting
He built a 2-ft prototype
1959 one person hovercraft was built
8/4/2019 27507856 Hovercraft Presentation
http://slidepdf.com/reader/full/27507856-hovercraft-presentation 5/19
One Person Hovercraft
8/4/2019 27507856 Hovercraft Presentation
http://slidepdf.com/reader/full/27507856-hovercraft-presentation 6/19
SRN 4 Hovercraft
8/4/2019 27507856 Hovercraft Presentation
http://slidepdf.com/reader/full/27507856-hovercraft-presentation 7/19
Design
Can be powered by one or more engines
Small crafts have a single engine with the
drive split through a gearbox
Usually one engine drives the fan
responsible for lifting the vehicle
The other forces air from the back andpushes the craft forward
8/4/2019 27507856 Hovercraft Presentation
http://slidepdf.com/reader/full/27507856-hovercraft-presentation 8/19
Working
Two main principles:
– Lift
– Propulsion
A skirt is required to quarantine airflow
No contact with ground, hence friction is
eliminated The shape of the body affects stability
All parts are essential for proper working
8/4/2019 27507856 Hovercraft Presentation
http://slidepdf.com/reader/full/27507856-hovercraft-presentation 9/19
8/4/2019 27507856 Hovercraft Presentation
http://slidepdf.com/reader/full/27507856-hovercraft-presentation 10/19
Parts
Lifting fan: Usually
used is a centrifugal
fan
When rotated air is
sucked into the center
hole
It is coupled via agearbox and connected
to the engine
8/4/2019 27507856 Hovercraft Presentation
http://slidepdf.com/reader/full/27507856-hovercraft-presentation 11/19
8/4/2019 27507856 Hovercraft Presentation
http://slidepdf.com/reader/full/27507856-hovercraft-presentation 12/19
Parts (Contd.)
Thrust propellers: Anaircraft type with variable
type pitch blades Diameter ranges from nine
feet to nineteen feet
In bigger crafts, the
propellers are rotated In smaller ones, rudders
are used
8/4/2019 27507856 Hovercraft Presentation
http://slidepdf.com/reader/full/27507856-hovercraft-presentation 13/19
Parts (Contd.)
Skirt: Flexible strip fitted below bottom
edges of the plenum chamber
Most sensitive design, it protects the craftand helps to lift it even higher
Engine: Earlier engines were piston type,
now gas turbines are used Consists of a compressor, to compress air
8/4/2019 27507856 Hovercraft Presentation
http://slidepdf.com/reader/full/27507856-hovercraft-presentation 14/19
8/4/2019 27507856 Hovercraft Presentation
http://slidepdf.com/reader/full/27507856-hovercraft-presentation 15/19
Parts (Contd.)
Air box: Placed right above the fan
Prevents air from escaping the fan
Power: 15 ft long and 7 ft wide weighs
about 2000 lbs, power taken would be
19 lbs/sq.ft
Requires 4 Hp/sq.ft = 176 Hp to lift thecraft 1ft above the ground
8/4/2019 27507856 Hovercraft Presentation
http://slidepdf.com/reader/full/27507856-hovercraft-presentation 16/19
Piloting a Hovercraft
The friction with the ground is minimum
People say best way to ride is by leaning
back and forth like a jet ski
It is possible to do a 360 degree turn
without stopping even once
8/4/2019 27507856 Hovercraft Presentation
http://slidepdf.com/reader/full/27507856-hovercraft-presentation 17/19
Conclusion
In theory hovercrafts are simple machines
But a plethora of problems exist to make a
functioning hovercraft
The plans and designs must be flawless
To build a hovercraft one must be well
aware of the demands of construction
Only then can one design a hovercraft
8/4/2019 27507856 Hovercraft Presentation
http://slidepdf.com/reader/full/27507856-hovercraft-presentation 18/19
References
Wikipedia – The free encyclopedia
www.quicktechhobby.com
Google search
8/4/2019 27507856 Hovercraft Presentation
http://slidepdf.com/reader/full/27507856-hovercraft-presentation 19/19
THANK YOU