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