Hovercrafts are advanced vehicles, conceptualized in the beginning of the last century, and brought into reality in the 1930s, by Soviet Russia. Since then, commercial hovercrafts have been designed and operated in civilian as well as defense applications. The advantage of these vehicles is their all terrain use. They can move over land, water, and air. They are veritable fortresses, floating in air. This characteristic makes them indispensable, in defense applications. You might recall seeing a hovercraft in the action sequence from 'Die Another Day', where 007 escapes from the Korean military base.
Projects are an important part of your science education. Science is not just reading books. The real fun of learning science is in applying scientific principles to understand the various phenomena in nature and apply it to solve real problems in life. Science teaches you about the physical laws of nature. Applying those simple laws, we can create machines like the hovercraft that float on air. As Napoleon Hill has said, 'What the mind can conceive, it can achieve.' Man has to be realistic, but that does not mean you stop imagining. Imagine, conceptualize, and work on bringing your concept into reality. That is applied science or engineering.
Science fair projects are opportunities to learn and have a lot of fun. How about creating your own little hovercraft? Though your miniature version won't solve your transportation problems, it will certainly give you an idea about how they work. The one that you will learn to build here will actually lift you off the ground. So let us get started with the assembly instructions.
Things You Will Need
This is the list of essentials.
- Battery-operated leaf blower or vacuum cleaner with blower outlet
- Hard plywood square sheet, 3 feet or 4 feet in length, ½ inch thick or a round table top, around 50 inch in diameter, with the same thickness
- A thick plastic sheet, which is 1 foot larger in diameter than the above plywood sheet (An old shower curtain or visqueen sheet will do.)
- Plastic disc (Could be a coffee can lid), 6 inch in diameter, about 1/8 inch thick or a wooden disc of same dimensions)
- 2 inch bolt, 1/4-20
- Nut, 1/4-20
- 2 Fender washers
- Electric saw
- Staple gun
- Duct tape
- Old bike tires or duct tape
- Smooth floor for operation (Smooth concrete floor will do)
Building Your Own Hovercraft
Here is a stepwise procedure. If you are still in school and have no experience with using tools, take the help of someone who knows how. Watch and learn.
Step 1: Make the Round Wooden Disk
Draw a round disk outline, of desired diameter, on the square piece of plywood. Cut the plywood along the outline. You can also keep it square, but then round is safer, as square edges may hurt. Next, mark the exact center of the disk or square. Drill a hole in the center, about 5/16 inch in diameter. Check that the 2 inch bolt passes through it easily.
Step 2: Make a Hole for the Leaf Blower
Next, you must make another hole for the leaf blower. The hole should be about halfway between the center and the edge of the disk or square. Keep the leaf blower or vacuum cleaner, face down on the plywood and draw an outline of its mouth. Then, cut out the hole and make sure that the leaf blower snugly fits into that hole. Once inserted, the mouth of the blower must be level with the underside of the disk.
Step 3: Stick the Plastic Sheet Skirt
Spread the plastic sheet on the floor. Keep the plywood disc over it. Wrap the plastic sheet over the disc totally, such that one whole side of the disk is wrapped in it. Make sure that this wrapping is tight but not too tight.
When air is blown into this plastic sheet, it is going to inflate and if it's too tight, it will tear. This will ground your hovercraft instantly and its hovering days will be over. Use a staple gun to staple the plastic wrapping tightly. Staple at regular intervals along the edge of the disk. You could also use duct tape and secure the plastic in place. This forms the 'skirt' of the hovercraft. The plastic sheet side is its bottom.
Step 4: Fix the center bolt and make holes in plastic.
Next, it is time to put the center bolt in. Drill a hole through the small disk and keep it at the center bottom of the disk. The bolt head should be on the bottom side and everything should be aligned in the following order: the bolt, washer, and the plastic disk on the bottom side and then another washer and fixing nut of the bolt, on the other side.
Next, cut small holes in the plastic sheet, about two inch in diameter, around the small plastic disk. Make sure that the holes are not too close as otherwise the fabric tears.
Step 5: Fix the leaf blower and then it's hovering time.
Once you are done with the holes, the disk is completely ready for launch. Fix the leaf blower in the hole made for it. Place the disk on a smooth floor surface. Lift it up a bit and then start the leaf blower. The skirt will inflate and it will start hovering over the ground.
This is a simplest method to make a hovercraft. The air cushion pressure, created under the disk, counterbalances gravity and eventually, it lifts the vehicle in air. Thus, the principle of working of this vehicle is simple enough to explain. The amount of weight a hovercraft can lift, completely depends on the amount of air pressure created under it, by the air cushion. If you want a more powerful craft, install a more powerful blower.
Hope you enjoy working on this project. If you find any flaws with this construction, then make improvements and keep improvising, till it starts hovering.