The Helios high-thrust plasma propulsion concept is targeting to realize a unique new thrust generation behavior. The major benefits of chemical propulsion (high thrust) and electric propulsion (high efficient fuel utilization and continuous thrust generation) are supposed to be combined.

Helios is basing with its main ionization system on inductively coupled devices. Reason is, the circular closed generated currents prevent collisions of charged particles with thruster structure; corrosion is reduced.

The intention is now, to increase the number of per time ejected particles and so the thrust. This is realized by ionizing a fuel gas under higher pressure conditions and forming by this way the basis for ejection of large numbers of particles. Therefore, Helios is using a two-staged discharge; the pre-stage is establishing the starting conditions and the main-stage is caring for the volume discharge of the fuel gas.

A magnetic coil at the thruster exit is aligning the charged fuel particles and generating thrust in this way.

Helios one is a full electric concept with a capacitive discharge as pre stage and an inductive discharge as main stage.

One feature of Helios to realize this high thrust levels is the two-stage ionization system of Helios. This systems consists of a pre-stage and a main-stage. The task of the pre-stage is to form a local plasma and provide the proper conditions for the main-stage. The intention behind is to ionize a neutral gas under higher pressure conditions and create in this way a basis for the extraction of large amounts of fuel per time; in other words to create high thrust.

Right after establishing the Plasma Rocket Company, we focused on the proof of concept of our two stage ionization system. In detail, we set up an experimental infrastructure to operate an electric propulsion device; a vacuum system, neutral gas feed and electric supply. And we constructed a prototype of the ionization system together with an ionization chamber.

The results of this experimental campaign were very promising. Basically of course, we were proofing the concept of our two-stage ionization system. But above this, we were already able to form a stable plasma over a broad pressure spectrum, almost up to atmospheric pressure conditions. And we operated the ionization system with two different neutral fuel gases; pure Argon and a mixture of Argon and ambient air.

Helios two is a hybrid thruster with a chemical combustion as pre stage and an inductive discharge as main stage.