APLR (air pressure launched rockets)...stomp rockets

For those not familiar with stomp rockets, these are for those who like flying inexpensively. The cost of engines and rocket kits can be daunting. I started out with these a few months ago, there's a builder- designer over on the papermodelers site name Yogi, he does alot with kids in school and developed the design for these. Mike Bauer from Alaska has taken then to a new level. When I got into them I started off with the basic design of the launcher but after going through several plastic bottles I started searching for some thing better. The first launcher design I found on the net but found some draw backs to it so I redesigned it.

The first pic is of the basic design, it's actually used with a two liter plastic bottle but tey6 don't last long so I hooked up a pump for camping gear. This grew old quickly also so I built the launche found on the net. The problem with this one is you have to have a tabble to set it on unless you like squatting down alot and the table you use can't be too high or the tire pump hose won't reach.

The last one is just a redesign of the first and adapted for rocket launching specifically. I eliminated one nintey and one of the pipes. It has the same capasity as the first by lengthening one of the tubes.

Here are a few flight shots, you can achieve some pretty impressive hights.The highest I've achieved sofar is 100 feet, this all depends on air pressure, the PSI tube and size of the rocket.

The Sat-V on the left is the stomp rocket, it's 1/144 scale. Mike Bauer is woeking on one of these thats siw foot tall.

There is a problem with these, they go up strait and fast and come down strait and fast causing extensive cone dammage, luckily they are designed so you can build extra cones. I've been working on one with a parachute recovery but haven't quite got the design down. I made a cone with a fishing bullit weight in the tip thats attached with fishing line. When the rocket noses over the weight slides out snatching the cone off deploying the chute. However there are still a few problems with this design, I'm still experimenting.

This is one rocket that really has potential for conversion. The Black Bart

You can use the "spud gun" technique to launch as well. Less gear to carry out into the field, and much less work to launch. And you can get some serious altitude if your combustion chamber is large enough. I developed this technique simply as a quick/simple/cheap method to test my homebrew avionics, but I've had a lot of fun playing with it in its own right.

If you don't have any avionics for deployment, it isn't terribly difficult to fashion a pneumatic shock absorber to prevent damage from the inevitable lawn-dart landings.

rockets4kids said:

You can use the "spud gun" technique to launch as well. Less gear to carry out into the field, and much less work to launch. And you can get some serious altitude if your combustion chamber is large enough. I developed this technique simply as a quick/simple/cheap method to test my homebrew avionics, but I've had a lot of fun playing with it in its own right.

If you don't have any avionics for deployment, it isn't terribly difficult to fashion a pneumatic shock absorber to prevent damage from the inevitable lawn-dart landings.

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Doesn't the spud gun use some sort of excellerant? The ones I've seen used had hair spray for prepulsion.

Here's a little APL rocket, they're really easy to build. The PSI tube is CRUCIAL in the rockets, too tight and they don't slid off the launch tube, the plug in the top has to be secure.

Engine farings, fins and cm

Quick and fairly easy, abiut four hours of build time. These could easily be used with engines.

closet astronaut said:

Doesn't the spud gun use some sort of excellerant? The ones I've seen used had hair spray for prepulsion.

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Yes. Hair spray makes a sticky mess, and from what I hear, fewer and fewer brands of hair spray actually work any more. I've had excellent results with denatured alcohol. I'm currently working on metered propane injection.

If you want to keep things *really* simple and safe, you can go with the classic stomp rocket approach and use a 2 or 3 litre soda bottle. I recently stumbled onto a stash of box-wine bladders which could work even better if I can figure out a way of plumbing them up.

Actually you can build a compressed air spud gun that is far safer and less noisy, you may want to look up designs for that, more height too.

rockets4kids said:

Yes. Hair spray makes a sticky mess, and from what I hear, fewer and fewer brands of hair spray actually work any more. I've had excellent results with denatured alcohol. I'm currently working on metered propane injection.

If you want to keep things *really* simple and safe, you can go with the classic stomp rocket approach and use a 2 or 3 litre soda bottle. I recently stumbled onto a stash of box-wine bladders which could work even better if I can figure out a way of plumbing them up.

Click to expand...

At this point I couldn't go back to bottles, but getting the pressure up to 35-40 psi with a bicycle tire pump gets old fast. portable air tanks empty and need electricty to refill. A new type launcher utilizing starter fluid and a lighter. We used to make cannons fron three inch exhaust pipe, smash one end flat using a torch brun a small hole in the end, stuff some rags in the open end. Using the torch fill the pipe with oxyceteline wave the flame over the small hole and ...BOOM!

Could this some how be converted to put over the end of a paintball gun barrel? I know it gives off quite a good shot of air when you shoot..... Interesting idea.

deffinantly..just make the PSI tube the same diameter as the barrel. Wrap a piece of paper around the barrel, mark an overlapping glue line and glue, just make sure the PSI tube slide on and off the barrel easily.