Minimum risk low altitude airspace integration for larger cargo UAS

Current initiatives for UAS airspace integration mostly aim at small or medium sized drones. However, it can be foreseen that there will be a demand of cargo UAS for payload in the range of about 1000 kilograms. It proves to be a challenge to integrate those larger drones into a national airspace. The concept of choice for this problem is the minimum risk configuration (MRC). This means that, instead of maximizing aircraft reliability by including more and more complex system components, the vehicles are routed along dedicated trajectories, so that an eventually occurring accident results in no fatalities and is foreseen to cause only monetary losses. The advantage of the MRC is that the concept can be realized using existing technology, with only moderate effort in new onboard sensory equipment. However, this poses some further challenges concerning air traffic procedures. In Germany and more generally in Europe, the airspace is densely populated, especially in the vicinity of airports. An MRC is meant to interfere with this existing structure in the least possible way. Therefore, an integration concept needs to make sure that the future air cargo system can avoid every potential risk strategically or at least tactically, be it a populated area, industrial infrastructure or other aircraft. We present an integration concept including recommendations for airspace structure, communication infrastructure and information management. Based on publicly available data for population and ground infrastructure, we show exemplary calculations that make the applicability of this concept plausible.