Current space transportation systems are based on the principle of momentum conservation of classical physics. Therefore, all space vehicles need some kind of fuel for their operation. The basic physics underlying this propulsion principle severely limits the specific impulse and/or available thrust. Launch capabilities from the surface of the Earth require huge amounts of fuel. Hence, space flight, as envisaged by von Braun in the early 50s of the last century, has not been possible due to this concept. Only with novel physical principles, providing the proper engineering principles for propellantless propulsion, can these limits be overcome. The concept of gravitational field propulsion represents such a novel principle, not being based on the movement of extremely large masses (e.g., planets or stars), but by the capability of building devices for the generation of gravity-like (i.e. acceleration) fields in a way similar to electromagnetism. In other words, gravity fields should be technically controllable. Since a propulsion system based on gravity-like fields has to function in empty space, it has to interact with the spacetime field itself. At present, physicists believe that there are four fundamental interactions: strong (nuclei, short range), weak (radioactive decay, short range), electromagnetic (long range), and gravitational (long range). As experience has shown over the last six decades, none of these physical interactions is suitable as a basis for novel space propulsion. Furthermore, none of the advanced physical theories, like string theory or quantum gravity, go beyond these four known interactions. On the contrary, recent results from causal dynamical triangulation simulations indicate that wormholes in spacetime do not seem to exist, and thus, even this type of exotic space travel appears to be impossible. However, there seems to be genuine evidence of novel physical phenomena, based on both new theoretical concepts as well as recent experiments that may have the potential to leading to propellantless space propulsion technology, utilizing two novel fundamental long range gravity-like fields that should be both attractive and repulsive, resulting from the interaction of electromagnetism and gravity. The current theoretical and experimental concepts pertaining to the physics of gravity-like fields are discussed together with recent experiments of producing extreme gravitomagnetic fields, performed at the Austrian Institute of Technology (AIT). The fundamental theoretical concepts termed Extended Heim Theory, EHT, are presented, and by further applying the physical ideas of EHT, it is argued that, in contrast to the circumferential gravity-like fields observed in the experiments at AIT, gravity-like fields acting parallel to the axis of rotation of the cryogenic disk may be producible, which should be strong enough for propulsion purposes. The basic experimental setup along with respective technical requirements as well as the resulting acceleration are described.