Thread by @fluxart1

Technology for pollution-free "electric flight" is being evaluated in a number of NASA Glenn Research Center programs. One approach is to drive propulsive fans or propellers with electric motors powered by fuel cells running on hydrogen. 1/5

For large transport aircraft, conventional electric motors are far too heavy to be feasible. However, since #hydrogen fuel would almost surely be carried as #liquid, a propulsive electric motor could be cooled to near liquid hydrogen temperature (-423 °F) 2/5

by using the fuel for cooling before it goes to the fuel cells. Motor windings could be either superconducting or high- purity normal copper or aluminum. The electrical resistance of pure metals can drop to 1/100th or less of their room-temperature resistance at liquid 3/5

H2 temperature. In either case,super or normal,much higher current density is possible in motor windings.This leads to more compact motors that are projected to produce 20 hp/lb or more in large sizes,in comparison to on the order of 2 hp/lb for large conventional motors. 4/5

High power density is the major goal.

core.ac.uk/download/pdf/4… 5/5