The stratosphere is the highest layer in the atmosphere where aircraft can still fly. Nevertheless, it is presently rarely exploited for commercial aviation. As Europe’s Vision for Aviation predicts globally a six-fold increase in passenger by 2050, flight levels above the troposphere become attractive and maybe the only way to realize this. While the lower stratosphere could still be reachable for classical aircraft, the higher altitudes would demand for higher speeds. Various technologies, systems and novel aircraft concepts related to high-speed transport have progressed rapidly over the last 20 years showing their technical feasibility and readiness up to TRL-3. Technology roadmaps elaborated by industrial and research teams indicated their readiness-level can easily be brought up to TRL-6 by 2035 provided the related application can be shown to be commercially exploitable. The first project goal covers the multi-functional integration of propulsion, aerodynamics, airframes and on-board systems acros