Kiwi static fire: L-1

Tomorrow, USCRPL will be conducting our first operation of 2013: a series of three static fires in our 4" filament-wound motor case. The primary objective of the tests is to gather performance data on our usual propellant formulation as well as on burn rate suppressants.

Each test has one grain weighing about 3.3 pounds. The first grain is our normal propellant made of ammonium perchlorate and aluminum. The second has some oxamide, (CONH2)2, which according to motor chemistry calculations should slow down the rate at which the propellant burns. Oxamide has been tried by the lab before with inconclusive results, but this time we have a more homogenous grain and better data gathering capabilities. The third grain has melamine as an additive, C3H6N6, which is an another burning rate suppressant.

The benefit of slowing down the burn is that a high-performance vehicle such as Traveler would lose less energy due to drag, not need as much thermal protection material, and not be subjected to as high an acceleration. The data we gather during tomorrow's firings will inform the design of our future vehicles.

It's also worth noting that this will be the third time USCRPL has used a filament-wound motor case, and the first time that one will be reused. That will be a noteworthy achievement in itself.

One final technology that this project is helping develop is head-end ignition. Usually, to light the motors on our rockets, we insert an igniter up through the nozzle and connect it to a ground-based power source. But for the upper stage of Texas Two Step (...more details on that soon...) we need the avionics to send current to an igniter below the motor bulkhead. We'll be testing our method for doing that during these firings, albeit without avionics involved. Basically, we have an insulating insert in the forward bulkhead, with screws going through it to transmit the electricity.

You may be wondering about the name for this static fire -- Kiwi. Our hope is that the motor will remain as flightless as the bird.

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