Water Rocket Forum

Hi, I am a belgian student of the sixth year secondary school and I study sciences and mathematics.
We need to do a research about physics, geography, biology or chimics. Our group will do research about waterrockets: What's the ideal water/air ratio, what's the best kind of wings and noses,...
currently, we are searching for a system to attach the wings to different diameters of rockets and for a way to fit different noses to the different bottles. If anyone has suggestions about how doing this, please comment.
Also, currently, as a parachute deployment system, we have tried the normal NOAA method, but the nose gets pressed tight on the rocket and won't come off. Now I am thinking on a chimical methode with vinegar and sodium carbonate (baking powder) in a film canister with a balloon attached. the balloon will inflate and so puch the nose of the rocket to set free the parachute. As a parachute, we use a sort of pilot chute. Why doesn't anyone else use this kind of parachute? It's ropes can't tangle, so it's more reliable.

Could the deploy system work? Maybe a little bit more info: the vinegar is in a little cup in the canister, the baking powder is loose in the canister. At apogee the vinegar makes contact with the baking powder and the balloon inflates.

Toy clockworks (aka tomy timers) are much more reliable and less messy.

And what about the pilot chute as a parachute? I agree, it is a bit more difficult than a normal one, but the folding doesn't require a technique (just don't wind its cord around it).

I agree with bugwubber on the tomy timer over the Vinegar + Baking Soda method. If the two don't mix correctly you may end up with a lawn dart, too much of a risk for me.

As for the pilot chute, as far as I am aware that should work fine. I have yet to have a standard chute tangle to the point where it failed to slow down the rocket enough.

The best thing to do would be to put together a test rocket and give it a try!!!

Thanks for the helpfull information!

We're trying to make an arduino-based servo deploy, based on the launchpad alTImeter from uswaterrockets (http://www.uswaterrockets.com/documents ... manual.htm). This will also fix our problem with our altimeter: a garmin wrist-worn altimeter like the image (in the link below), wich would severely outbalance the rocket and will only record once in a second.http://images.esellerpro.com/2295/I/243 ... erf-lg.jpg (sorry couldn't get it in the post).
There is only one problem: I don't know how to program the auto-apogee deploy
Is there anyone who can help?
already, thanks

Here is some code that shows the apogee detection code.

thanks. My dad (a rookie when it comes to programming) also came up with another way. Code is posted later (now I am to buzzy preparing everything for the test week. Sadly, it's raining and windy here, so it could be we won't be able to launch.

Awesome! I can't wait to hear how it turns out!

Idee voor de vinnen: Lijm je vinnen op een andere fles, knip ze uit een laat een paar cm plastiek steen rond de vin en plak ze met plakband op een raket naar keuze. Op die manier maken wij al een paar jaar raketten.

Discovery WR wrote:Idee voor de vinnen: Lijm je vinnen op een andere fles, knip ze uit een laat een paar cm plastiek steen rond de vin en plak ze met plakband op een raket naar keuze. Op die manier maken wij al een paar jaar raketten.

Als je naast mijn naam kijkt, dat is de manier waarop we het uiteindelijk hebben opgelost. Ze hingen vast aan een soort van metalen kooi. Het geheel met hoogtemeter en kooi woog ongeveer een halve kilo en we zijn tot een hoogte geraakt van 40 meter (een druk van 7 bar) met een fles van 1,5 liter met daarin ongeveer 0,6 liter water (1/3 van het feitelijke volume van de fles).
Maar als ik ooit nog eens start, zal ik zeker denken aan deze manier.