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A couple of weeks before the UKRA '99 event I ordered a load of parts from Pete's Rockets, amongst these parts were two of the new 2.6" PML Quantum Tubes. I already had an idea of what I was going to build with one of them but I had no idea of what to do with the second one. As it turned out I didn't get the parts until a couple of days before the event and there was no time for me to build the intended rocket.
After the International Rocket Weekend at Largs I sat down with RockSim and designed two rockets for two new motors I wanted to fly, one of them was the R.A.T.T. Works H70 and the other the new Aerotech 29mm I200. I didn't want both of the rockets to be constrained design wise to having to fly on the H70, so I designed one rocket for each motor, although Mongrel, the other rocket, will fly on all the 29mm motors I have except the R.A.T.T. Works I70 which is just a shade too long.
I used RockSim to calculate a rough altitude for the I200 and it came out with a value that was too high for me to use single deployment at apogee with the flying sites that I use. So I knew I would have to build dual deployment into the rocket and loose a little bit of altitude with the slightly increased weight of the altimeter bay. I just happened to be at Pete's Rockets one Saturday and got the tube cut and slotted in all the right places and a set of G10 fins made up, everything was ready for the construction.
I've finally managed to get this rocket into a flyable state for the Thurst meeting at the weekend, I also managed to fly it on my I200 that I've had since last October. The flight wasn't perfect in that it didn't go straight up so it was no where near the 4,000 foot RockSim prediction. Even then it was no where near 10% off the RockSim prediction and ended up round about 3,012 feet.
The rocket is a bit on the stable side, about 2.12 calibers with an I200 installed, so it waether cocked a bit in the light wind. I think I also need to move the upper rail guide a bit closer to the center of gravity, as this might result in a better take off.
Other than that the only thing I can bitch about is RockSim and the I200 motor files I've got, the simulation reckoned a 29-30 Gee take off. On initial downloading it was apparent that it was about half of that, so what's going on there I've got no idea... When I get the file from Pete Davy's Palm Piolt I'll graph it and post the data here.
Mean while look out for me at the next Thrust launch with another I200 as I try to get that I altitude record of over 3,400 feet.