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, May 10, 2011

Polaron G2 flight day report

I've uploaded the update from this weekend's NSWRA launch on our main website here:

The update includes photos and video of the Polaron G2 launch. The flight was encouraging for us in order to keep pushing further with the G2 development. Although the 210psi launch pressure was 20% lower than what the rocket was designed for, we decided to at least get a couple of good flights in before increasing the pressure again. Also encouraging is that the simulator results from two different simulators predicted the altitude quite accurately for this flight. This means we can continue to use the simulators to predict the behaviour of this class of rocket.

The G2 in this configuration still has room for improvement on two fronts. Each 10psi increase in pressure beyond the 210psi adds around 50 feet to the altitude. These pressure chambers have been hydro tested to 270psi. The rocket is designed to be extended by a further spliced-quad like we used in the first attempt. This extra spliced quad should add a further 100 feet or so. How the rocket stands up to higher speeds and stresses is unknown at this stage, so more fights will follow.

We also flew a second high pressure rocket on the day - Axion G2 - that is based on the Axion series of rockets. The rocket flew well, but failed to deploy the parachute and crashed. I can see the G2 name is going to get confusing here. The 'G' in the name simply stands for "Glass"-reinforced and the 2 is just the second in the series.


jkdenham said...

Hi George does sound very different, very nice flight. You are starting to get some nice performance from the Polaron G2 rocket, 240 meters is a nice altitude.

Jeremy - DY Water Rockets

dan b said...

Hey George
Very nice video i really enjoyed it all the rockets performed well axion was my favourite i have been waiting to see how jet foaming works at a higher pressure well done George
keep up the work
Dan B

Anonymous said...

HI Georg,

for the last couple of weeks I am following your projects and enjoying the knowledge of your webpage.
I was looking to see the G2 finaly fly but for the first time I can`t open the youtube video "This video includes content of beggars and is not available in your country".
It would be great if you could post it somehow that I can enjoy it here in Germany as well.

Keep up the great work
Greetings from germany.


MariusD said...

Hi George,
Great to see G2 finally did fly, according to plan ! :) Deployment time was accurate also!
The idea with that tube (you called jet foaming) is a good one. In all situation, with or without foam.
I was fixing this problem with a speed launch, so it could not drop all the water in the lower chamber! You can do this with Robinson Coupling, not Tornado.
If you use altimeter in all your rockets I think is a good idea to modify the software so you can use the altimeter to detect the apogee!
Great fly! I am looking for the next ones.

Todd said...


Congratulations on the successful Launch of G2, its a wonderful looking rocket. I would think the 1000' mark is well within reach of this class of rocket :)


George Katz said...

Thanks guys. :)

@Anonymous (Jorg): I noticed that it was blocked in Germany. I have uploaded the video to Vimeo here:
Hopefully that is not blocked.

@MariusD: We try to not fly the altimeters too often, as we don't want to break them. :) But eventually we plan on integrating a barometric sensor into the FC. For now the timer works well with the Magnetic Apogee Detector (uMAD from Whooshtronics)

@Todd: Thanks Todd, You're going to enjoy launching your dragster at the higher pressures and bigger nozzles. :D This rocket reached a peak velocity of ~270km/h. You can expect similar speeds from your dragster, especially with the multiple nozzles. :)

MariusD said...

I was planning also to integrate a barometric sensor into FC. I am thinking to buy a microcontroller with ADC (i.e. PIC16F88, also from Microchip) for this, but the sensors I found are not cheap.
Do you have some suggestion on sensor?

cyril said...

Georges super flight!
I'd say the third flight was good ;)

lucrockets said...

hey George
I'm following your rocket work closely. I try many things from you too. i was waiting to see flying the G2. It was a great flight! I wonder how the G2's with boosters are going to fly.

luc of team lucrockets

George Katz said...

Thanks Luc,

We too are looking at how to mount the boosters at the moment. It is going to be slightly different to the previous versions simply because of the forces involved. But should be a fun one to launch. :)