Advanced gas turbine engines will remain the backbone of large aircraft propulsion in any foreseeable future. However, competing electrically based technology for ultra-low emissions is advancing quickly at the lower end of the power spectrum. The key question here is whether battery-hybrid or fuel cell electric power could scale up to the high-volume market segments: For short regional flights, battery-based power injection to the gas turbine cycle is attractive. Fuel cells might become relevant for higher power classes, too, when synergistically combined with gas turbine engines. A potential sweet spot could be revolutionary single gas turbine hybrids for short-to-medium range aircraft.
