2 Stage Water-Powered Rocket?

[Skylon]

I was thinking of making a simple water-powered rocket, but then I started to wonder if a two stage rocket was possible without external control. I was thinking of some kind of electromagnet/capacitor release, with the magnet attached to the first stage and an iron ring on the second stage. The biggest problem is pressurising/connecting the second stage for launch without the pressure and water escaping before the stages connect. And the electromagnet and iron may be too heavy to make it worthwhile.If anyone else could have a go, that would be cool  

Edited May 13, 2017 by Skylon

[wumpus]

I clicked the link thinking about a toy from my youth [1970s, although I think the toy dates from the 1960s].  I'm guessing it was the same tech as a supersoaker only pointed down (I don't recall trying to use one as a water pistol, then again it would be hard to fire and there was no throttle).  I think there was a more expensive model with a standard (small) rocket and a larger first stage.  I suspect when the water pressure of the base dropped enough below the water pressure of the top stage, a spring released and launched the top stage.

Don't expect the thing to go too high.  The only thing slowing down the flight down was the angled rear fins that made the thing spin on the way up/down.

[Zeiss Ikon]

Water rocket fliers have been doing two and even three stage birds for decades.  Do some digging on YouTube and Google and you'll find lots of information on how they pressurize the upper stage (I believe it's done through the first stage nozzle), how they control staging, and even how they arrange parachutes to deploy at apogee rather than when the upper stage is empty.  The altitude record, last time I recall, was over 2000 feet.

[Ultimate Steve]

http://aircommandrockets.com/

You're welcome.

They've done one launch that was two staged with boosters and probably hold the altitude record for non-fiberglass water rockets.