Apparatus for generating a unidirectional force comprising a first looped track and a plurality of reaction engines, and wherein the first looped track comprises a first straight path, a first curved path, a second straight path, and a second curved path and the reaction engines move along the different paths of the first looped track, wherein said reaction engines are configured to operate according to the following steps a) to d): a) each of said plurality of reaction engines in the first looped track is activated and accelerated in the first straight path of the first looped track with a controlled predetermined force magnitude in order to gain kinetic energy and once the said reaction engines reach the end of the first straight path of the first looped track their predetermined force will be deactivated and, b) each of said plurality of reaction engines in the first looped track which has gained said kinetic energy will enter the first curved path of the first looped track with a high velocity and travel along this path and exert as a result of the reaction engines movement along the first curved path of the first looped track a unidirectional force to the looped track and, c) each of said plurality of reaction engines in the first looped track is decelerated along the second straight path of the first looped track by means of drag forces acting against the reaction engines by activating a parachute system, and once the reaction engines reach the end of the second straight path of the first looped track having a low velocity the parachute system will fold back, and, d) each of said plurality of reaction engines in the first looped track will move along the second curved path of the first looped track with a low velocity and will be positioned at the stage at the beginning of step a) again and such that the steps a) to d) are carried out for each of said plurality of reaction engines in the first looped track cyclic such that said plurality of reaction engines travel around the first looped track and accelerate said apparatus; wherein a second looped track is fixed to the first looped track back to back and wherein said plurality of reaction engines in the second looped track is configured to operate analogous to steps a) to d) in said second looped track such that those of said plurality of reaction engines running along the first looped track move in an opposite direction than those of said plurality of reaction engines running along said second looped track in order to achieve a combined unidirectional force acting on said apparatus. a) each of said plurality of reaction engines in the first looped track is activated and accelerated in the first straight path of the first looped track with a controlled predetermined force magnitude in order to gain kinetic energy and once the said reaction engines reach the end of the first straight path of the first looped track their predetermined force will be deactivated and, b) each of said plurality of reaction engines in the first looped track which has gained said kinetic energy will enter the first curved path of the first looped track with a high velocity and travel along this path and exert as a result of the reaction engines movement along the first curved path of the first looped track a unidirectional force to the looped track and, c) each of said plurality of reaction engines in the first looped track is decelerated along the second straight path of the first looped track by means of drag forces acting against the reaction engines by activating a parachute system, and once the reaction engines reach the end of the second straight path of the first looped track having a low velocity the parachute system will fold back, and, d) each of said plurality of reaction engines in the first looped track will move along the second curved path of the first looped track with a low velocity and will be positioned at the stage at the beginning of step a) again and such that the steps a) to d) are carried out for each of said plurality of reaction engines in the first looped track cyclic such that said plurality of reaction engines travel around the first looped track and accelerate said apparatus;