http://www.youtube.com/watch?v=tYd6leIxmuo&search=rocket
You have to see this to believe it, even after you see it you still wont beleive it
I don’t believe it.
The Mythbusters tried to replicate what those crazy Japanese claimed to have done without any real success.
What a hoot!
(I didn’t think that would work)
Used to shoot “Bottle Rockets” like that with the boys. The DCSF guy thought it was a hoot and went to get himself a stopper so he could show his kids. Of course, we used the air compressor 
I’m assuming this works like the water powered pump rockets you used to be able to get at the five and dime … the air you pump in blasts the water out a small nozzle for thrust …
How do you make it work with a soda bottle?
Furthermore … being a Mythbuster fan, but having missed that episode … how did the guys get all the bottles to go at once?
The part I like the best in the video is the “parachute” made of net … it doesn’t slow the boost phase down any but seems to help the guy have a bit softer landing at the end … some neat physics there.
Looks a bit like the human cannonball approach to “Punkin Chunkin” if you ask me … 
So … who will be the first to adapt this to railcar propulsion?
Matthew (OV)
They may be barmy , but you have to admit , it looks bloody funny . And cleverly done , too .
Mike M
Matthew (OV) said:
So ... who will be the first to adapt this to railcar propulsion?Matthew (OV)
Perhaps using Diet Coke and Mentos???
Yes, it’s just a 2 liter water rocket.
You need a football needle, like for blowing up basketballs, and a stopper that fits tightly into the neck of the bottle. Stick the needle through the stopper, fill the bottle about 1/2 way with water, hook up your air pump and stand out of the way. The tighter your stopper fits the farther the bottle will go when it blows the stopper out.
ja, sure, you betcha! did that last week. NOT!
Have you seen the idiots trebucheting themselves into a lake? Looks like fun, but one girl ruptured her spleen when she hit the water. See http://www.trebuchet.com and scroll down.
If you find barefooted boy with a lego trebuchet on that site, that’s my Ethan.