Fraunhofer-GesellschaftThe ASPIRER project develops and validates an additive Aerospike engine manufactured in INCONEL 718.In collaboration with the Institute of Aerospace Engineering at TU Dresden, the project demonstrates how additive manufacturing enables the realization of complex, actively cooled Aerospike rocket engines, a concept that has remained largely experimental for over 60 years.Funded by the European Space Agency (ESA), ASPIRER addresses one of the key challenges in modern propulsion: improving efficiency under varying atmospheric pressures.
Why an Additive Aerospike Engine?
Compared to conventional bell nozzles, the Aerospike concept offers:
- Altitude-adaptive thrust optimization
- Potential fuel savings up to 30%
- Improved theoretical propulsion efficiency
- Enhanced performance for reusable launch systems
The major historical limitation:The spike operates in the hot gas stream and requires efficient cooling to prevent melting.Additive manufacturing with integrated near-surface cooling channels now makes this feasible.
Manufacturing Chain
The additive Aerospike engine is produced using:
Laser Powder Bed Fusion (LPBF)
Heat treatment
Precision machining of functional surfaces
Thermal coating of the spike
Welding of shroud and spike
The complete process chain was validated regarding:
Mechanical properties
Manufacturability
Process stability
Destructive and non-destructive testing
Publications:
https://doi.org/10.2351/7.0001121
https://doi.org/10.1007/s12567-022-00476-7#
https://doi.org/10.13009/EUCASS2025-552
Click here to visit the website of the project.
Contact:
M.Sc. Samira Gruber
Fraunhofer Institute for Material and Beam Technology IWS
Mail: samira.gruber@iws.fraunhofer.de
