Welcome to the Water Rocket Forum, sponsored by The Water Rocket Achievement World Record Association.

Since our founding in 2003, we've become the largest, most sophisticated and ground breaking group supporting you, the serious water rocket flyer! Whether you are a beginner or an expert, the WRA2 has something for everyone.

A water rocket is a type of model rocket using water as its reaction mass. The pressure vessel (the engine of the rocket) is constructed from thin plastic or other non metallic materials (usually a used plastic soft drink bottle) weighing 1,500 grams or less. The water is forced out by compressed air. It is an example of Newton's third law of motion.

WR-car competition rules discussion

Discussions about water rocket powered cars, sleds or boats.
Post Reply
User avatar
RaZias
WRA2 Member
WRA2 Member
Posts: 751
Joined: Mon Jul 14, 2008 3:16 pm

WR-car competition rules discussion

Post by RaZias » Wed Nov 03, 2010 2:35 pm

I see that in no way a WR-car might have guiding system that is outside of itself.

But I wonder if we can use a guiding rail like we do for 9mm nozzle rockets ?

Maybe a rail of the the same lenght (or with the doble of the lenght) of the WR-car could help in a WR-speed competition.

So is this acceptable ?


Research and Development is the soul of WR

User avatar
thampson
Current WRA2 Dragster Speed & Distance Record Holder
Current WRA2 Dragster Speed & Distance Record Holder
Posts: 230
Joined: Wed Jul 16, 2008 8:19 am

Re: WR-car competition rules discussion

Post by thampson » Thu Nov 04, 2010 8:17 am

RaZias .. :)

I dont think it will make much difference to be honest to keep the car straight after it leaves the guide rail. I know when we started making 1 bottle cars that they started out straight for the first few metres then did a 90 or 180 degree turns if we had too much thrust. Have a look at these videos to see what I mean

Look at 1:35 of this video, as soon as we had too much thrust (140psi) it spun, less thrust it went pretty straight
http://www.youtube.com/watch?v=xzi8r7S6Cp8

Also this one, look at 1:37, left hand 90 degree turn when there was too much thrust, you will see at 120psi the same car went pretty straight
http://www.youtube.com/watch?v=bW_n7lh0WYo

Having said that I cant see why a guide rail shouldn't be allowed for the first 2m or so.

-todd-


HHWRSA
Hornsby Heights Water Rocket Space Agency
http://wrocket.hampson.net.au

User avatar
U.S. Water Rockets1
WRA2 Member
WRA2 Member
Posts: 1771
Joined: Sat Feb 03, 2007 3:24 pm

Re: WR-car competition rules discussion

Post by U.S. Water Rockets1 » Sat Nov 06, 2010 10:26 pm

thampson wrote:RaZias .. :)

I dont think it will make much difference to be honest to keep the car straight after it leaves the guide rail. I know when we started making 1 bottle cars that they started out straight for the first few metres then did a 90 or 180 degree turns if we had too much thrust. Have a look at these videos to see what I mean

Look at 1:35 of this video, as soon as we had too much thrust (140psi) it spun, less thrust it went pretty straight
http://www.youtube.com/watch?v=xzi8r7S6Cp8

Also this one, look at 1:37, left hand 90 degree turn when there was too much thrust, you will see at 120psi the same car went pretty straight
http://www.youtube.com/watch?v=bW_n7lh0WYo

Having said that I cant see why a guide rail shouldn't be allowed for the first 2m or so.

-todd-

For a competition, the guide rail should be limited in length to something reasonable. It might be a good idea to say that the maximum length of any guide system would be two times the length of the car. That would be an easy to verify size that could be checked in photographs and videos.


Team U.S. Water Rockets
Visit USWaterRockets.com
Visit our Blog
Tune in to our YouTube Channel
Visit our Facebook page
Visit our Twitter Page
Opportunity is missed by most people because it is dressed in overalls and looks like work. --Thomas Edison

Post Reply