German startup POLARIS Spaceplanes has completed the test campaign of its 1kN AS-1B linear aerospike engine, a version of which will power its MIRA demonstrator.
MIRA is a 4,25-metre-long demonstration vehicle that is equipped with four kerosene-fed turbine engines and one of the company’s LOX/kerosene linear aerospike engines. Testing under the power of its four turbine engines began in early November with an initial flight lasting 2.5 minutes.
The first ignition of the company’s AS-1 aerospike engine occurred in late November on a test bench constructed on the grounds of a decommissioned airport in Northern Germany. Since then, the company has completed a total of ten hot fire tests, completing the test campaign for this version of the engine, which is heavier and designed primarily to be used for ground testing.
Over the course of testing, the company achieved stable and reproducible thrust generation with no damage or wear detected between ignitions. The results of this phase of testing have given the POLARIS team the confidence to move ahead with testing the first flight-ready version of the engine.
POLARIS plans to begin testing this lighter, more sophisticated version of the engine, designated AS-1F, this week.
Currently, POLARIS is working towards the first flight of its MIRA demonstrator under rocket power before the end of the year. However, the company has told European Spaceflight that weather forecasts currently do not appear to be favorable. It is, however, confident that teams will at least be able to perform a rocket-powered roll test, which will be the last major milestone before the first flight is attempted.
MIRA is the fifth subscale demonstrator of the company’s AURORA multipurpose spaceplane and hypersonic transport system. With the aid of an expendable upper stage, AURORA is designed to be capable of delivering 1,000-kilogram payloads to low Earth orbit. Before work on this operational vehicle begins, POLARIS intends to build and test a final demonstrator vehicle called NOVA. Testing of this sixth and final demonstrator will begin in 2024.
