Cold flows 6–10 yielded significantly improved results compared to the initial five. When we opened the MVAS to release LN2 from the tanks through the injector, the system operated smoothly; however, the desired data was not being captured. Fortunately, as VTF approached, both our cold flow performance and data output showed continuous improvement.

Our first vertical test fire did not go as planned, despite the success of our final cold flows. The engine failure was due to our ablative material not being rated for the conditions it was exposed to. Instead of burning as expected, it accumulated at the nozzle inlet, obstructing the flow. This blockage caused combustion to cease while pressure built up in the chamber until the material was forcibly dislodged, ultimately leading to an explosion.

Our second engine test was partially successful. We fixed the problem from the first test by switching to a new heat-resistant material called canvas phenolic, which worked well. But during the test, the engine had a rough start, which blew off part of the nozzle and melted the injector. This was caused by poor cooling in the fuel lines. To fix it, we need to move the main valves closer to the injector, like they would be in a real launch. That change requires another test to figure out how powerful the engine is and how long it can run. Because of that, we probably won’t be able to launch before summer, and we’re also redesigning the injector just in case cooling wasn’t the only issue.