HOVERCRAFTS

P RE S EN

TAT I ON

BY

AYUSH

SH

AR

MA

OUTLINE OF PRESENTATION Introduction History Elements of typical hovercraft Operation of the hovercraft Advantages Disadvantages Applications of hovercraft Future of hovercraft Conclusion

HOVERCRAFT What is a Hovercraft? A hovercraft is a vehicle that “flies like a plane,

float like a boat, drive like a car. A Hovercraft , also known as an air cushion vehicle

or ACV, is a craft capable of travelling over grass, water, mud or ice and other surface.

Hovercraft are hybrid vessels operated by a pilot as an aircraft rather than a captain as a marine vessel.

HISTORY

The first design by Swedish designer Emmanuel Swedenborg in 1716.

In 1915 Austrian Dagobert Muller built the world first ‘water effect’ vehicle.

In 1931 finnish aero engineer Toivo J. Kaario began designing a developed version of a vessel using an air cushion and built a prototype.

INVENTION

He invented the hovercraft and patented in 1955. With diligent work he was able to bring his idea to reality with the first commercial hovercraft in 1959. British hovercraft corporation developed the first commercial hovercraft for passenger. From there on the idea took with numerous developments with the vehicle.

1952 Sir Christopher Cockerell (British Engineering)

ELEMENTS OF A TYPICAL HOVERCRAFT Propeller:-

It pushes the hovercraftahead by pushing air behind.

Fan:-

Primary purpose is to inflatethe cushion containing withinthe skirt beneath the craft aswell as to provide thrust withwhich to propel the craft Forward.

ELEMENTS OF A TYPICAL HOVERCRAFTHull

This is where the driver operates the hovercraft and passengers or cargo are located. It is the main body of the hovercraft which acts as the base for attaching of the other parts.

ELEMENTS OF A TYPICAL HOVERCRAFT

Lifting SystemThis consist of a centrifugal fan attached to a motor or an engine, which provides air for the cavity underneath the craft (called the plenum chamber) and also for filling the skirts.

ELEMENTS OF A TYPICAL HOVERCRAFT

Thrust SystemThis consists of propeller that moves air from in front of the craft and accelerates it out the back. This accelerated mass of air then generates thrust which pushes the craft forwards.

ELEMENTS OF A TYPICAL HOVERCRAFTSkirt

This is the flexible wall that is attached all around the bottom of the craft. The skirts prevents the pressurized air from escaping from the plenum chamber.

ELEMENTS OF A TYPICAL HOVERCRAFT

EngineA typical hovercraft uses one engine but larger sizes can use more sometimes up to six engines. They usually utilized the typical marine engines since they are quieter and fuel efficient.

ELEMENTS OF A TYPICAL HOVERCRAFTControl System

This consists of a set of rudders that steer the craft by directing the air from the thrust system toward either left or right which consequently steers the craft.

The lift fan pushes a large volume of air under the hovercraft which is prevented from escaping by the skirt.As the fan continues to force air into this cushion, the pressure under the hovercraft increases. When the pressure under the hovercraft exceeds the weight of the hovercraft, the hovercraft begins to rise off the ground this can be around 6’’ to 105’’ depending on the size of the craft.Eventually the hovercraft raises high enough to lift the skirt off the ground.Air begins to escape through the gap between the ground and the skirt (called the hovergap).At some point the hovercraft reaches equilibrium point at which the amount of air being forced into the cushion can not exceed the amount of air escaping through the hovergap.At this point the hovercraft is hovering at its maximum hover height.Fans mounted on top creates thrust air which is used to propel the hovercraft forward and moving the thrust air with rudders controls hovercraft direction.

OPERATION OF THE HOVERCRAFT

Brakes & Steering

SteeringSteering is accomplished by use of the rudders. The rudders are placed at the back of the craft in the direction of the thrust air flow. As the direction of the rudders are changed so is the direction of the craft.

BrakesHovercraft have no braking system. Simply reduce power until the craft no longer hovers. Thrust reversers can be used.

OPERATION OF THE HOVERCRAFT

Fuel Consumption

This will depend on the speed and other conditions which the craft is driven under. But it uses less fuel as compared to cars and boats under the same condition.

OPERATION OF THE HOVERCRAFT

Advantages • Travel over any surface.• Shortcutting routes.• Travel in dry water beds.• No collision with debris, logs etc.• Access to 75% of coastal area instead of only 5%

with conventional vessels.• Hovercraft are very fuel efficient as hovercraft do

not have to plough through the water but “fly” above the surface. At maximum speed fuel consumption of a hovercraft is approx. 70% less than of a fast petrol boat with similar payload capacity

Disadvantages• They move a lot of air and can be relatively

loud(Noise Pollution).• Steep grade can be issue.• Potential of skirt damage.• Not exactly agile(e.g.: cornering).• The hovercraft is bulky and its high speed make it

difficult to control while on land.

APPLICATION OF HOVERCRAFT

Future of Hovercraft• The future of hovercraft seems uncertain, but there is good chance

there will be huge port all over the world. Thinner hovercraft might be built so civilian can drive safely on road.

• Development in Neoteric Hovercraft Technology• The future is more promising than ever before.

• The hovercraft is in operation today throughout the world for variety of purpose and its use is growing giving raise to new and improved designs resulting in greater applications.

• With its safety and adaptability it can become one of the most important and economic transport in future.

CONCLUSION

• www.google.com• http://images.google.co.in/

images• http://en.wikipedia.org/wiki/

hovercraft• http://en.wikipedia.org/wiki/

aircushion

REFERENCES

THANK U!

THE END