Water rockets are plenty of fun, but they can be even more fun if you go wild with the engineering. [The Q] is one such experimenter, who built a dual-thrust water rocket that even has a parachute for landing!
The dual-thrust concept is an interesting one, and is well explained by fellow YouTube channel [Air Command Rockets]. The basic idea is to use several chambers on the water rocket, one which provides an initial short “boost” phase of high acceleration, followed by a longer “sustain” level of acceleration from a secondary chamber.
It’s a great way to send a water rocket ever higher, but [The Q] didn’t stop there. The build was also fitted with a wind-up module from a little walking toy, colloquially referred to as a “Tomy timer” in the water rocket scene. A rubber band is wound around the timer’s output shaft, holding a door shut containing a parachute. At launch, the windup mechanism is released, and its output shaft turns, eventually releasing the parachute. The trick is setting up the timer to release the chute just after the rocket is done with its thrust phase.
It’s a neat build, and one that would serve as a great guide to those eager to start their own journey down the rabbit hole of advanced water rockets. We’ve seen similar work before, too. Video after break.
This is great ! I remember the plastic water rocket with the pump that I had as a kid. I think it was 2 stage as well. Maybe this could work as a sounding rocket with some kind of guidance system. I wonder if a Mentis/Coke rocket would generate more thrust?
Here is a 2 stage water rocket with parachute.
https://youtu.be/0qzOzjRJpaU
Mentos (darned autocorrect)
It does make me wonder, how many bottles could be, practically, strapped together and how high could this sort of set up reach. I do quite like the idea of a purely mechanical rocket. Perhaps some sort of multistage ignition system could be implemented, by using sequentially triggered wind up motors and depleted stages could be jettisoned.
The rocket equation, that you have to lift all the mass of the fuel (in this case, pressurized water) with more fuel, says this is going to get pretty limited pretty quickly, but it would be cool to see a multistage.
I’m wondering about using an accelerometer to sequence both multiple stages and the parachute.
Check out Air Command: http://www.aircommandrockets.com
He’s done that experiment and more. Wonder how high you could make a carbon-fiber 1000 psi water rocket go? He’s got your answer.
Like the drilled cork plug and release system. We used all rubber truck tire stem