Tuesday, May 6, 2008
The goal of this project is to send a sugar motor rocket into space. This will be a fairly large rocket, and will contain two combustion chambers and one nozzle. In effect, it has the longer thrust duration of a two stage rocket, or a slower burning fuel, by having a booster motor and a sustainer motor that both share the same nozzle. After the burnout of the first motor chamber, a delay will burn through the bulkhead at the top end, igniting the next motor.
"Sugar propellant used by amateur rocketry experimentalists worldwide due to its inherent simplicity and safety, is not a high performance propellant. Therein lies much of the challenge of this project."
If this project works, it will be a huge step as only the third amateur rocket on record to get into or near space. (I include the RRS boosted dart as essentially a space launch, though technically it did not appear to hit space.) As of right now, only one team has ever made it to space... that would be the CSXT with the GoFast rocket (ugh what a name, the things you have to do for sponsors). However, the GoFast rocket had a huge amount of funding and was nearly commercial in nature. I would welcome this far more amateur attempt because it is far more of a grassroots type project. Yes amateur can be a good thing.
"Besides the extraordinary goal of sending a rocket into space, there are other equally important and more fundamental goals. This project is intended to be universal in scope with regard to involvement, and as such, participants from around the world are invited to join in this quest. It is hoped that the Amateur Experimental Rocketry community, which over the past decade has grown in size and in collaboration thanks to the internet, will bond even more closely -- to share our ideas, experiences, successes and failures. Other goals include expanded development of "sugar propellant" technology, leading to greater knowledge and enhanced safety of sugar propellant rocketry. And no one can argue that success of this project would provide incontestable legitimization of the remarkable "sugar propellant". Last, but not least, it is hoped that attention spurred by this project will promote an interest in science & technology and begin paving the way for future "rocket engineers" to take us further."
I hope that the Sugar Shot works, and that we will soon be launching amateur rockets to space on a regular basis.
I have added a new image that goes over the general math for the expected Sugar Space Shot. The project is clearly behind schedule, by as much as 2 years, but there is hope that they will still finish. Most space shot rockets are never built, either people run out of money, time, or interest.
Note the expected mass fraction (amount of rocket mass made up by propellant): about .8. That would be very impressive, and would certainly improve their odds of using this kind of fuel (lower ISP) to get to space. If they get this rocket built to .8 mass fraction, that would impress me as much as the space flight! One big reason why professional sounding rockets do so well but ours dont (the Super Loki Dart is an M-N-O sized rocket that hits the edge of space) is the mass fraction issue. We need to begin to fix that if we want to keep pushing altitudes higher.
Also, you can clearly see in this description (as well as on the web page) that this rocket will have a single motor, that will burn in two stages. That is, the motor parts will be the same but with a middle bulkhead that will have a burn-through delay of 14 sec (I think after first stage burnout?). This will give the rocket some very valuable seconds of coast before the motor burn continues, this will greatly reduce drag loss and greatly increase altitude. Is this as good as a two stage rocket? Not even close, but like the boosted dart technique, it is still pretty darn good. A boosted dart R motor or two burn R motor will both do better altitude than your typical R motor (something like the Go fast rocket, but that was an S) that burns for say 14 sec. only. I have never seen this two burn motor technology used in solid rockets, but it has been done in the past. I do not know Sugar motor design very well at all. My question would be - why not simply use a moon or slot burner, or even an end burner in the grains? Would that not also help extend the burn? Would liftoff thrust be too low in that case?
Anyway, I will keep an eye on this inspirational project and make updates as needed. Probably in new posts as this one is about full.