I like the idea of fuel cells, but hydrogen's going to have an image problem as soon as people see the failure mode, if it's just being stored as H2 in compressed tanks. Liquid fossil fuels and electric batteries burn with a gradual flame. Hydrogen suddenly detonates, with a supersonic, shattering shockwave, if it's mishandled.

Even with Cold War money, Lockheed's famed Kelly Johnson couldn't make the logistics work for the CL-400.