On Tuesday 30th August the Norwegian subsidiary, Nammo Raufoss AS, conducted a static firing of their first full-scale hybrid sounding rocket motor, a part of the Norwegian Sounding Rocket (NSR). The firing was a great success!
The rocket motor, tank/valve system and mobile ground support equipment have been designed in cooperation with Lockheed Martin Michoud Operations, New Orleans.
All production and testing have been performed by Nammo Raufoss AS.
The purpose of the NSR is to launch scientific probes to investigate the atmosphere around the North Pole.
The rocket motor stands over 10 meters tall in flight configuration. The main tank was filled with 200 kilogram of liquid oxygen, which serves as the Oxidizer for the motor. The combustion chamber consisted of a solid fuel grain. The rocket motor was ignited using a special non-pyrotechnical igniter. All structural components were made of Aluminum.
The propulsion system was controlled by an in-house developed computer system that worked flawlessly during preparations procedures, static test firing and post-test operations.
The complete burn time for the static firing was set to 20 seconds. The rocket motor is capable to burn for 35 seconds. The successful test demonstrated several of the flexibility and safety aspects with regards to hybrid propulsion systems.
No pyrotechnical elements were part of the rocket motor and it could at any point during the burn be shut down, which was also demonstrated.
Post-test analyses of recorded pressure and thrust parameters showed a rocket system that matched the predicted values of the design very well. Demonstrated peak thrust was close to 30kN. The pressure-time curves showed stable combustion during the complete burn. The flight weight combustion chamber was structurally intact and in very good post-test condition.
The success of this first full scale test opens the road for further tests and the development of operational hybrid rocket propulsion systems!