This past Saturday I successfully fired my first LOX hybrid motor at the FAR site. It was a busy day as I also launched our 75mm Sugar Shot to Space small scale sustainer. I am fortunate enough to have many friends that helped make both projects a success. The sustainer was recovered intact and will be launched atop our small scale booster that has now had 3 successful static test firings.
The LOX hybrid was fired three times on Saturday using 2 different fuel grain formulations. The first firing did not completely burn the fuel grain due to low pressure and filling of the tank. We then fired the second grain as the first grain was being refurbished for a second burn. Being my first LOX motor, it was for evaluation only for a larger one. It proved so successful that several of my solid motor friends helping now want to build their own LOX motors...it was impressive!
Because of the low Isp of sugar motors I have not seriously thought about the N-Prize (we've been working on a sub-orbital vehicle). Now with this LOX motor, it changes everything.