On 17.7.2019 it was time for the maiden flight of the STR rocket “Asimov”. A first flight is always something exciting, you can never be sure that everything will go well. This time it didn’t
Three days before, on July 14th, five of us left Vienna heading for France. After 24 hours of driving and little sleep we started to prepare the rocket feverishly right after our arrival. We wanted to qualify for launch on that day. In the end this did not work out because we could not pass all technical tests immediately. The next day we went back to work in the morning and fixed the problem that held us back before. However, we were confronted with the next, seemingly troublesome, problem: the ejection of the parachute took place too early. This electronic problem could be solved quickly and we qualified for the start in the morning of the 17th of July. After countless separation and other tests we were quite confident to have a nominal start.
Around noon the truck of the French military brought us to the launch pad. We mounted the rocket at the tower, activated our electronics and checked our telemetry. Everything looked good, we received data and we were all hopeful. After we had gone to the starting tent the pyrotechnician installed the motor. Our hands were now tied and we could only hope that everything would go smoothly.
The countdown started and after the “Ignition” was announced from the loudspeakers, the rocket engine roared and the rocket took off. The first seconds of the climb were completely nominal. Then suddenly, the fins broke off at maximum acceleration and the rocket started spinning around wildly. The forces on the rocket caused the nosecone to seperate and the parachute was ejected and opened, but the shekel, which connected the parachute with the rocket, did not cope with the non nominal separation speed of more than 500 km/h and broke off. This lead to parachute and rocket descending separately. The rocket hit the ground with a speed upwards of 100 km/h. The parachute couldn’t be found.
Unfortunately we could not retrieve the rocket on this day, because it was already too late.
On the next day we left early in the morning in an off-road vehicle and found the rocket after a short search. We were somewhat suprised to find out that the rocket was almost completely undamaged, except for the fins that broke off during flight. Our onboard electronic was still fully functional and we were able to evaluate and retrieve all flight data (including video!).
After a year of hard work not everything worked, but “shit happens”. Furthermore, we learned a lot and know exactly what we want to do better next time. There will be a second flight of STR-09 Asimov in the near future. But this time fully nominal!