Advantages of plug-in hybrid electric vertical take-off and landing aircraft with hydrogen energy storage

Electric vertical take-off and landing (eVTOL) aircraft are becoming more and more attractive due to the improvements in electric road vehicles, and the mounting demand for new urban air mobility. As here discussed, due to the low specific energy density of batteries, hybridization of the propulsion system with fuel chemical energy storage and electricity production on board by either an internal combustion engine and generator, or fuel cells stack, appears to be a better avenue to deliver performance (cruise speed, range, and payload) than using only large and heavy batteries at least through 2030.