MagnetIc NOzzle thruster with elecTron cyclOtron Resonance

Electric propulsion has been identified by European actors as a strategic technology for improving the European competitiveness in different space areas such as in-space operations and transportation. In recent years, ONERA has built up an expertise on the ECRA (Electron Cyclotron Resonance Accelerator) disruptive technology for electric propulsion, and the need for further maturation along with Europe’s search for new technologies lead to the MINOTOR project (MagnetIc NOzzle thruster with elecTron cyclOtron Resonance).

MINOTOR’s strategic objective is to demonstrate the feasibility of the ECRA technology as a disruptive game-changer in electric propulsion, and to prepare roadmaps paving the way for the 2nd EPIC call of 2020, in alignment with the overall SRC-EPIC strategy.

picture-minotorBased on electron cyclotron resonance as the sole ionization and acceleration process, ECRA is a cathodeless thruster with magnetic nozzle, allowing thrust vectoring. It has a significant advantage in terms of global system cost and reliability compared to mature technologies. It is also scalable and can potentially be considered for all electric propulsion applications, from microsatellites to space tugs.

Although the first results obtained with ECRA have been encouraging, the complexity of the physics at play has been an obstacle for the understanding and development of the technology. Thus in-depth numerical and experimental investigations will take place in MINOTOR.

The main objective of the project is to bring the ECRA technology from TRL3 to TRL4/5, in order to demonstrate its potential in a large range of thrust levels. To reach this goal, the following achievements are planned:

  • Get a full understanding of the physics, by deep numerical modelling studies in parallel to an extensive experimental investigation, leading to optimised designs, performance maps and scaling laws for the thruster;
  • demonstrate ECRA performances with tests at three thrust levels (30 W, 200 W and 1 kW) and with erosion tests;
  • demonstrate features such as compatibility with alternative propellants and magnetic beam steering;
  • demonstrate the feasibility of an efficient microwave generator, and tests it on the thruster;
  • determine quantitatively the impact of the ECRA technology on the EP system, including the PPU (Power Processing Unit), and on the satellite platform, and establish the future industrial roadmaps for development. These roadmaps shall aim at realising a high TRL in the timeframe of 2023-2024.


The 36 months MINOTOR project (2017-2019) involves 7 partners from 4 countries. The consortium is composed of academic experts to perform the research activities on ECRA, along with experienced industrial partners to quantify its disruptive advantages on the propulsion subsystem and its market positioning.

logo-onera-identONERA (France, Coordinator) will be in charge of most experimental investigations of the thruster configuration.
acronimo University Carlos III de Madrid (Spain) will develop the codes and implement the numerical modeling of the thruster.
hd_logo_thalesThales Microelectronics (France) will demonstrate a high efficiency microwave generator technology.

jlu-logoUniversitaet Giessen (Germany) will conduct the higher power tests (1 kW) and the erosion test on the 200 W prototype.

logo-tasThales Alenia Space Belgium SA (Belgium) will investigate the impact of the ECRA technology on the PPU architecture and cost.

LOGO_SAFRAN_rvbSafran Aircraft Engines (France) will provide expertise in electric propulsion thruster production and performance.

logo-l-up              L-up (France) will help on the project management.

ECRA’s advantages as an electric thruster technology can be a disruptive force in a mostly cost-driven satellite market. The MINOTOR project will result in a significant step in maturity, and will help assess its potential to improve European competitiveness, help develop low-cost satellite missions such as constellations, and provide end-of-life propulsion solution, while paving the way for other future emerging electric propulsion technologies.

For further information visit the MINOTOR website (www.minotor-project.eu/)