Sizing and Synthesis Approach for a Hybrid Unmanned VTOL System

Unmanned systems are becoming more popular and the VTOL segment of this market has risen sharply over the recent few years. This increase can be largely attributed to its low-cost nature and ease of entry for hobbyists. As a result of economies of scale, VTOL capability in the small/mid-size UAV market offers huge advantages to the operator. This market, in both civil and military use, can be projected to grow very quickly over the next decade—provided regulators bring into place conducive safety measures. The addition of mature hybrid-electric propulsion technologies to VTOL systems can have a major impact on their capability, operating cost, safety, fuel consumption, and the environment. This paper covers some of the performance improvements and design implications for VTOL hybrid-electric propulsion systems (HEPS).