Blog #14 | Success, and now for Round 2!

We finally did it! This past Friday was the first ever successful hotfire of our hybrid engine, Runaway. After two years worth of setbacks, research, and development, we produced thrust! This is truly an exciting time to be a part of UNH SEDS.

Now that we’ve had our first test, we’re currently working around the clock to fix and adjust as many components as we can before our 2nd hotfire, planned for this Friday. There was a lot to learn from this test and we discovered so much about what our design is doing well and what went wrong. 

After inspecting the engine itself and the footage from the hotfire, we believe that the pressure in the chamber wasn’t high enough to create a sustainable combustion. Our igniter also performed better than previous tests, but the oxidizer time delay was too short to create a flame front along the entire engine. The fuel grain had too small initial surface area, which we want to be higher in order to have as much thrust as possible right at the beginning. Our sensors performed fairly well overall, but there were a few calibration issues which caused some of our data to be noisy.

While these all seem like they would make our test a failure, it was far from it. Every single problem we found from the hotfire is a valuable learning experience for our engineers. Failure is an essential part of the engineering design process, and success never comes without a few hiccups along the way. Just over the past few days, we’ve been able to find solutions to nearly every problem. Reducing the size of the nozzle throat to increase pressure, mixing in aluminum powder to increase the regression rate of our fuel, tweaking the time delay of the oxidizer based on new mixtures of igniter. We’ve come a long way over the past year, and we aren’t going to stop advancing any time soon!