2 stage water rocket explosion

Today we launched the new 2 stage rocket, but things didn't turn out to well. The new 2 stage rocket has a 2L second stage instead of the 0.5L old rocket.We changed this because the small rocket wasn't secure when attached to the booster, it kept bending when it was full of water because it was too heavy. The new 2L sustainer has a ring fin that just slipped over the top of the booster. The staging mechanism is exactly the same as before.

When we launched it there was no wind and perfect flying weather, but it was only launched at 80psi because the staging mechanism was leaking. This may be the problem why it flew in a big arch. Its strange why the staging mechanism failed because it had worked in all our previous tests. The explosion was really loud and it echoed for while, we are so glad that it didn't land too close to us!

This rocket idea is going to be scrapped because we have had to many problems with 2 stage rockets, we will stick with using single stage rockets because they are much simpler and more reliable. The next project will probably be a new 8L rocket with reinforced bottles and we will attempt to beat our old record of 408ft

New 2 stage rocket

This is our new 8L 2 stage rocket, and it should work this time. The Flight Computer is between the two bottles (about half way down the booster) because it reduces the height of the rocket and probably reduces the weight too. Most of the things on the rocket are the same as the old 2 stage (staging mechanism and flight computer are the same). The only things that have changed are the pressure bottles and the booster's parachute system. The parachute for the booster is deployed when the sustainer is launched, the sustainer pulls a pin (at separation) and out flies the parachute, the parachute is also between the two bottles.

The weather forcast are forcasting 20mph winds for the next week, so i don't think it will be good rocket flying weather.

2 Stage water rocket update

Unfortunately, we haven't been able to fix the cluster launcher, so we have decided to make another 2 stage rocket that it isn't a cluster. The new rocket will be 8L (4 bottles coupled together) and will hopefully be more reliable because it is simpler (it only has one nozzle). The sustainer won't change and the staging mechanism will still stay the same too. This new rocket should be finished quite soon but we don't know when it will be launched because the weather forecast is not good.

When it is finished we will upload some photos and more details!

2 stage rocket CRASH!!!

The new 2 stage rocket was all complete until it was launched. On the launch pad it fell over and launched at a 45 degree angle, this was caused by one launch tube that wasn't secured in place. The launch tube came out of the launch and blocked one of the nozzles, this made it fly sideways. 

The only good news about this launch is that the staging mechanism worked, you can't see it in the video but if you listen carefully you can hear it separate. The next launch probably won't be for another few days because the booster will need to be rebuilt, luckily the sustainer was almost undamaged although it was fired towards the ground at 80mph. The rocket still managed to reach 111ft.

2 stage rocket

This our first 2 stage rocket and will hopefully break our personal record. The 2 stage mechanism is controlled by a Flight Computer that we bought from Aircommand water rockets and the release mechanism is pretty much the same. There is a servo that pulls the release on a garden hose connector and launches the sustainer. The launcher is very simple and it works, there are 3 male hose connectors that are being released by elastic bands and a piece of wood stops them from releasing until launch.

If none of this makes any sence to you, then watch this video:

If this links doesn't work click here

Details:

Booster

Capacity: 12L

Water: 3L

Weight: 745g (1075g with sustainer)

Nozzle: 3 x 7mm

sustainer

Capacity: 0.5L

Water: 0.2L

Weight: 140g

Nozzle: 5mm

Update June (cluster project)

Because of the windy conditions lately, we have be doing some thinking and have made a new launcher for a cluster rocket. The launcher is very simple and will hold high pressure (110psi+), I will update some pictures in a later update. The rocket will be a 2 stage and the rocket dart will be the second stage, the dart will be pressurised. The booster will be 12litres and will have 3 nozzles.

This is a 3d design of the rocket.

Details (these are only estimations)

Sustainer

Capacity: 0.5L

Weight: 140g

Nozzle: 5mm

Booster

Capacity: 12L

Weight: 600g

Nozzle: 3 x 7mm

new rocket dart design

This new dart design should be more reliable than the last design, now that we have added the new parachute system. The dart has been made longer to improve stability but other than that, it is still the same rocket. Another change to the booster, it is now a straight 4litre rocket with a 10mm nozzle, the problem with the cluster rocket is it couldn't hold very high pressures.

 The booster doesn't have fins because it is stable during the thrust phase of the flight and the dart separates at the end of the thrust phase, so the booster just tumbles back down to earth!

Rocket Dart

We have finally launched the rocket dart but it wasn't as successful as we had hoped, we launched it three times and it crash three times. We thought it would be a good idea to use an airspeed flap for the parachute deploy but it just increased the drag and made the rocket crash. The rocket will be modified to use a tommy timer (wind up mechanism) because this is more reliable! The highest altitude recorded was only 171ft so we were very disappointed. 

Dart Prototype

We have made a prototype dart and booster. The booster is a cluster, just the same as the drop away booster rocket except the boosters don't fall off. the dart uses an airspeed flap for the recovery system so it keeps the rocket simple. The dart will only carry the alitimeter but later models might have a camera.

Details

Dart

weight:   120g

Diameter:   40mm

Booster

Capacity: 5L

Weight: 260g

nozzle:  1x  10mm   

              3x  11mm 

Rocket Dart Idea

We have been looking at the Water Rocket Index and they have made a rocket/dart that is powered up to high speed using an ordinary water rocket (22mm nozzle for high speed) and then the dart coasts the rest of the flight. The dart is not pressurise but it is quite heavy, so it will carry a lot of inertia. The Water Rocket Index haven't put a payload on their dart but we thought that we could attach our altimeter on it and then make some kind of recovery system. They estimated theirs to reach 400ft at 100psi so we would like to run a couple of tests with this dart idea.

For more info, here is a link to their page:

http://ourworld.compuserve.com/homepages/pagrosse/h2oRocketRb.htm