Originally Posted by wjwj

Hi,

A question for any of you rocketry/chemistry experts out there. I am a radio-control enthusiast who has recently been experimenting with rocket motors. What I am trying to do is create a "rocket plane", but unlike typical rocket planes, I am putting much time and care into making a craft that is both light and aerodynamic to achieve high flights.

Here is my question: I want to use sugar motors (KNO3 and sucrose) to power this thing. I have made a few already, but the problem is that they burn way too fast with too much thrust. What I want to do is modify the motor to slow the burn. Here is my idea:

Add baking soda to the KNO3/sucrose mixture since baking soda is non-flammable. I know this is done to create a delay charge, but I don't want it to burn that slow. Also, I would probably decrease the nozzle diameter to accommodate the pressure decrease.

What are your thoughts on this? Does it seem doable? Are there any formulas/methods for determining how much baking soda to add? If I could extend the burn from ~2s to ~10s then I would be happy.

Thanks for your help!