This blog covers the day to day progress of water rocket development by the Air Command Water Rockets team. It is also a facility for people to provide feedback and ask questions.

Tuesday, March 01, 2011

Foam flights

This weekend we went to the NSWRA launch event again, but because we didn't have the Polaron G2 rocket quite ready yet, we just flew smaller rockets. These were basically assembled the night before launch out of spare components. The update is here along with a highlights video:

http://www.AirCommandRockets.com/day101.htm

8 comments:

Doug said...

Hey george

The bent rocket begining made me laugh :P So close yet so far for your moon landing there :)

Regards Doug

Rodrigo said...

hi George.
Do you know why the parachute didn´t came out the last time?

Regards Rodrigo

George Katz said...

@Doug: Heh Heh, ...yeah, we'll get there one day... I think we need more tape. :)


@Rodrigo I believe the parachute got stuck in the deployment mechanism. It was designed for a bigger parachute, and the ejection plate had a bit of a gap underneath it and I suspect it got stuck in there. We put a smaller parachute on the rocket to stop it drifting in the wind.

Anonymous said...

Good Show as usual George.

Being more of am arm chair water rocket entheusiast given how much time quality rockets can take, it is still interesting to look for possible improvements.

One thing I note is that nozzles wether from turbofans or jet ski motoes (see link below) have a 'bypass ratio' this aims to reduce the exahust velocity to more the same as the water speed/ air speed to increase the overall efficiency. Seems to be simply done by placing a scoop on the back which captures incoming air/ water from in front - mixing with the thrust medium - and togeather movingout the back togeather - fast moving and slow moving water/ air combined. I am not sure if it could apply to water rocket nozzles but in theory it should work. Maybe worth a look. Keep up the good work. Charlie

http://en.wikipedia.org/wiki/File:Pump_jet.PNG

George Katz said...

@Anonymous (Charlie)

This is a concept that does need looking into. It is similar to air amplifiers where high pressure air is used to move large volumes of air at slower speed. I have heard several people mention this approach now, but I haven't seen anyone actually build it. One drawback is the added weight and potentially some additional drag.

It would be interesting to do the maths to see what or if any extra efficiency/thrust one could generate.

Doug said...
This comment has been removed by the author.
Anonymous said...

It is the goal of my "diffuseur" system.
Dadu05
http://www.techno-challenge.org/fus/modules/newbb/viewtopic.php?topic_id=1705&forum=1&post_id=24983#forumpost24983

George Katz said...

Hi Dadu,

Good luck with the diffuser system. :) I think there is real potential for improving performance when combining air and water. Keep up the great work!