Polaris completes first inflight ignition of its aerospike engine
In what appears to be a first, Polaris Spaceplane on October 29, 2024 successfully completed the first ever inflight ignition of an aerospike engine, using its Mira-2 unmanned engineering prototype.
Later in the day on 29 October, MIRA II took off from Peenemünde Airport on the coast of the Baltic Sea with a takeoff mass of 229 kilograms, which represented a reduced propellant load. The vehicle flew to the ignition point over the Baltic Sea, approximately 3 kilometres away from the ground station, and once there, completed a short three-second burn of its AS-1 aerospike engine. During the short burn, MIRA II experienced an acceleration of 4 m/s².
According to the company, the engine operated at a reduced chamber pressure during the three-second burn, resulting in a fuel-rich combustion.
There have been several attempts in the past to develop the aerospike engine, none of which ever completed any test flights, as far as I am aware. The concept is that the thrust is released in a string of openings, with only one wall forming the nozzle shape and the atmosphere used to complete the nozzle on the other side. As the atmospheric density changes the nozzle shape thus changes its shape, producing the most efficient thrust throughout the engine’s entire flight.
More test flights will be required before the company will be able to begin work on its full scale Aurora spaceplane.
In what appears to be a first, Polaris Spaceplane on October 29, 2024 successfully completed the first ever inflight ignition of an aerospike engine, using its Mira-2 unmanned engineering prototype.
Later in the day on 29 October, MIRA II took off from Peenemünde Airport on the coast of the Baltic Sea with a takeoff mass of 229 kilograms, which represented a reduced propellant load. The vehicle flew to the ignition point over the Baltic Sea, approximately 3 kilometres away from the ground station, and once there, completed a short three-second burn of its AS-1 aerospike engine. During the short burn, MIRA II experienced an acceleration of 4 m/s².
According to the company, the engine operated at a reduced chamber pressure during the three-second burn, resulting in a fuel-rich combustion.
There have been several attempts in the past to develop the aerospike engine, none of which ever completed any test flights, as far as I am aware. The concept is that the thrust is released in a string of openings, with only one wall forming the nozzle shape and the atmosphere used to complete the nozzle on the other side. As the atmospheric density changes the nozzle shape thus changes its shape, producing the most efficient thrust throughout the engine’s entire flight.
More test flights will be required before the company will be able to begin work on its full scale Aurora spaceplane.