Ya I started a discussion on the Robot Fighting League forum on building a Hybride Rocket engine just for fun.
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Boy ya know as soon as a simple rocket motor design becomes known to the masses. Some fun loving folks find interesting ways to apply it to a bicycle just to see what happens.

Well Kiddies heres a nice application of a hybrid rocket motor similar to the one used on Spaceship one. Basically it's built from a Steel pipe linned with roofing ashphalt. A valve is attached to one end of the pipe and a bottle of nitrous oxide is attached to the valve.

Ignition is provide by a small chunk of a Estes rocket motor or a Safe and Sane sparkler. Thats about where the Safe and Sane part ends. Jeese I kinda want one of these. ;)

bikerodnkustom3.homestead.com/dan...html

The Propane powered Pulsejet bike is pretty cool too
bikerodnkustom3.homestead.com/jet...html

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This fellow Tim Pickens has built a lot of motors. For some reason I think I would like meeting him. Anyways heres a page with the internal drawings of the Hybrid motors and about 8 pictures down is the external motor case. It's pretty high tech stuff from your local Lowes or Home Depot hardware store.

realrocketman.tripod.com/rocket.htm

Hmm... Now if I could just get me a 2 Ft long 2 inch diameter schedule 80 pipe nipple and (1) 2 inch pipe cap, (1) 2 inch to 1 inch reducer and (1) 1 inch 6 inch long pipe nipple and a 25 lb chunk of roofing tar.

It looks like you could just hang a piece of 1/4 inch or 1/2 inch Steel rod in the center of the empty pipe and heat up the tar on a Coleman stove in a aluminum cooking pot and and just pour the liquid tar in the motor case and then pull out the rod after the tar had cooled a bit. And there ya go one loaded hybrid rocket motor. Now of course there are some picture on this page of a slighly better design with the bell shapes added to the output end of the motor case. These will enhance the motors performance.

I still havent figured out if there is a jetting orifice for the Nitrous oxide or if they are just dumping it into the motor with what looks like a 3/16 to 1/4 inch fitting and a simple valve.

Also on another interesting note Tim mentions on one page the use of a Salami being used as Fuel. Apparently the Fat in the Salami is being used a the Fuel. I love that one He He.

Some more Links.....

realrocketman.tripod.com/uncletim.htm

realrocketman.tripod.com/menu.htm

A little Rocket Math for the Math guys.
members.aol.com/cv192/engine.html

A audio interview with Tim Pickens. He wants us all to build rockets.
I like his way of thinking. Garage Builders Rule!
www.thespaceshow.com/detail.asp

www.harcspace.com/photos.php

home.hiwaay.net/~hal5/

www.hobbyspace.com/AAdmin/a...3-09.html

The bike Racing folks have some ideas about Rocket bikes and flywheel lanched bikes also.
bikerodnkustom2.homestead.com/IBRKA.html

Serious Rocket Racers from around the world....
meditech.ch/ete.dragracing/gb/index.html

So what happens to the Salami when it is used as a rocket fuel? Does it change it's chemical propertys enough to become a Hot Dog?

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So then I got to looking for an ignition source, Having built and launched many model rockets when I was a kid. I knew you could buy igniters for the solid fuel motors. I even made a few of my own a couple of times.

But of course I wanted to see how the Big (N) series motors are fired. I found this cool page on building igniters with Ni-Chrome wire some gunpowder and nitrocellulose lacquer. Apparently you can add a little Magnesium or Aluminum powder to give them a little more kick.

www.sparksrocketry.com/igniters.htm

Boy I wish I had some of theses back in my home made Cannon days. I used to just roll up some smokless powder in a cigarette rolling paper and stick it in the touch hole of the cannon. Then we would light it and run behind a concrete building and listen for the BIG bang.

Hmm... I wonder what happens when you add Nitrous Oxide to a Magnesium or Aluminum fire.

One day I was cutting some bolts off of some Surplus Aluminum plate and I tried cutting these strange looking bolts. Apparently some of the bolts were made from Magnesium. I noticed that they wouldn't turn Red when I heated them.

But Boy they sure lit up the garage when I hit them with the oxygen from the torch. I was sorta sad when I vaporized the last one. They were fun to watch. They made a pretty (brilliant blue white flash) and lots of sparks.

Disclaimer: Playing with fire is dangerous, be very careful.

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found this page when searching for more Data about hybrid rocket engines.
These guys have a lot of neat stuff for sale on their pages. And yes Boys and Girls some of it can be used in Robotic Combat. They even sell Exstreamly High pressure Pneumatic Valves. Not to mention that they even have kits for rocket engines and stuff

www.aeroconsystems.com/

I went for maximum p/w ratio, while trying to keep it as foolish yet simple as possible.

I got 4 10amp motors out of leafblowers, put them all in an old small tailgate style bbq pit, and have each motor independently drive a 4 inch wheel.

Havent really tested yet, but by the book at 110v that will produce about 6-8 HP, and the weight machine's weight is practically all motors. Will be fun to see how it does!