This is a record of the days we launched rockets and the
events that took place.
 

Team Members at Launch Event: PK, GK, John K and Paul K.
Number of launches: 5

We were really looking forward to today, after almost a month of tests we were going to fly both the foam and the baffle to see how static fire tests compare with the real thing.

Flight Day Events

• First off the pad was Polaron III. Since it was a first for us in using foam we decided not to fly the camera. From the tests we were expecting that the thrust will be fairly low on take off and so the rocket could tip over and fly horizontally! We also saw in the tests that the thrust phase was a lot longer, so we decided to set the deploy delay a little later too.
  
  We pressurised it to 120psi and launched. The rocket took off real slow and proceeded to accelerate leaving a beautiful foam trail behind it. It almost looked like a pyro rocket. The rocket arced over gently and the parachute deployed soon after the thrust phase so it didn't coast for too long. The total flight time was 29.88 seconds which was probably the longest for this rocket at this pressure. (typical flight is ~27 seconds for 130psi) Although we don't have qualitative measurements yet, we believe that foam even without a CD nozzle improved the rockets performance, but it is too early to tell - more tests are needed. The three seconds may no sound like much but the rocket was only at 120 psi, probably carried about 100 - 150 mL more water than usual, and the parachute deployed a little early.
  
  Water Rocket using Jet Foaming - very good
  
  (If the video does not play, try the latest Flash player from Macromedia)

  Compare the thrust profile for the same rocket at 130 psi pressure but with a normal water/air mix here: Day 25 Highlights video.

• The noise produced by the rocket is also very different to normal water/air mix. The audio is a more continuous noise with occasional hick-ups but no definite air pulse.
• We loaded it up again and this time put the camera in it. The rocket took off slowly again at a bit of an angle and proceeded to accelerate but now flying quite pitched over. We watched it disappear on the other side of the river. We did not see the chute deploy, and there was a cheer from the neighbouring baseball game. It took us about 10 minutes to find it, completely destroyed. The flight computer was still on, and the parachute was out, but not the secondary parachute. The main chute probably came out after impact. The camera survived and provided an interesting point of view of the flight. Later on Google Earth we measured the distance to the impact site from the launcher and it was over 200 meters. We are still investigating why the parachute failed to deploy. Well another excuse to rebuild the rocket - parts of it can be reused.
• We also flew J4 II with the foam and it also had a nice take off and left a great foam trail. The parachute deployed a little early, and the rocket landed well.
• We weren't game to test the 7mm nozzle as the total thrust on takeoff  is even less. We will try the 7mm nozzle with higher pressures.
• Because of the Polaron III crash we weren't able to fly the baffle to see what effect it has on flight. It will have to wait for the rebuild.
• We also tested an older rocket - Jordan with the 15mm nozzle and a 300mm launch tube. Quite a difference in take off speed is evident, and sounds more like a gun shot than the typical restricted nozzle flights. The rocket flew nice and high and survived the landing well despite having no recovery system.
• The launcher also sprung a leak at the hand tightened nut that attaches the different release mechanisms. We'll have to figure out why, but it is most likely that it just wasn't tight enough as we swapped the release mechanisms. It has been sealing fine up this point.

Flight Record

Notes to Self

• Put a beeper on the rocket to make it easier to find.