Summer Science Camp: Hovercraft

The summer we offered a middle school version of science camp, we had fun making hovercrafts.  The "teacher-versions" were the full 4' (diameter) circles.  We had a handful of kids and they each made their own from a 2' (diameter) circle of plywood.

We followed Daryl Taylor's instructions, which I'll let you read on your own. 

In short:
The hovercraft is basically a large circle of plywood covered with plastic.  A shop vac motor (one whose motor can be switched to blow) is attached to the craft.  The motor pushes air into the space between the wood and the plastic, creating a buble.  The plastic has several small holes in it - the air is forced out of those holes and in turn the craft is pushed up, hovering above the ground.  Left alone, the hovercraft will stay in one place - add an outside force and you'll start to see physics laws in action!

Here are some pictures to aid in your construction (sorry, no action shots - go here to see Daryl's in action).

The bottom side:

In the center you'll place something to hold the plastic down.  Most people would use a plastic lid, we used something my friend's husband had lying around in his workshop - I'm not even sure what it is! 

You'll notice that ring of duct tape - it's not just decorative!  It reinforces the plastic, so you can cut holes in it without shredding the whole thing.



The top:

A masterpiece in duct tape:

It really does take vast amounts of duct tape to make sure the plastic is held down and no air will leak out. 

In the above picture, you'll notice a small hole cut out, near the bottom of the picture, slightly to the left.  That's where your shop-vac hose will connect to the hover craft, turning it from a heavy-piece-of-plywood-covered-with-duct-tape into a hovering-piece-of-plywood-covered-with-duct-tape!

It's not the most beautiful contraption ever, but it is a very cool demonstration of all kind of physics principles and it really does work!