If the Eviation all-electric approach seems to stretch current technology to the breaking point, a Washington state startup called Zunum, with some backing from Boeing and JetBlue, is taking a more conservative, stepwise approach. Its 12-seat ZA-10 design is similar in size (and in its use of a V-tail) to the Alice, but 2,500 pounds lighter. (On paper, of course — every- thing is lighter on paper.) It has a couple of 650 hp ducted fans mounted on the aft fuselage, just as turbofans would be. In addition to an unspecified mass of batteries in its wings, it uses a 650 hp turbine generator as a “range extender.” For short stages, however, battery power alone would suffice.