Nowadays the aeronautical transport field is still widely based on internal combustion engines, even if a growing attention is paid to electric engines and in general to propulsion systems with low environmental impact. In this context, thrust generation by means of ions acceleration is a propulsion technique which could play a revolutionary role. At present, ionic propulsion is well operative in space applications but much less studied for atmospheric ones. It potentially allows to develop propulsion units with important advantages over thermochemical devices: first, the good thrust/(power consumption) ratio already attained at the current level of research, which is expected to increase dramatically as technology proceeds; moreover, the absence of any moving components and the light weight, together with the emission of naturally decaying gases without solid particles (no combustion at all).
The IPROP project aims to bring ionic air-breathing propulsion beyond the pioneering phase, exploring its capabilities and improving its performance. Cold plasma for atmospheric propulsion is a subject of recent investigations: model airplanes and vertical lifters have recently flown with this type of propulsion, but the potential of this technology is much higher.
To this purpose, a complete research program is proposed, starting from breakthroughs in fundamental research to be achieved through theoretical, numerical and laboratory studies. The following steps will lead to develop improved and optimized propulsive units, with the objective of designing and building an airship model (technological demonstrator) with ion propulsion. A further objective is the conceptual design of a full-scale stratospheric airship: a major long-term impact is expected for ion-powered airships, which could act as stratospheric platforms replacing many satellite functions, such as telecommunications, remote sensing and disaster risk management in civil protection, offering these services at much lower costs, with the benefit of being recoverable systems. A fully successful program may lead to top-level, fully ion-powered airships: thanks to the propulsive units without moving mechanical parts, powered by solar energy, they would have extremely long operation times, low maintenance and create very low pollution.
