[jmward01]

One thing I have been thinking about for electric is how it may allow completely different flight possibilities that could leap ahead of what we have now. For example, extremely high altitude flight is a huge challenge for current aircraft on a number of fronts, but a big one is how do you design an engine that can produce power at extreme altitudes. The higher you go the more heat limited you are in a gas turbine engine. Electric doesn't have that issue so it may be able to push aircraft a lot higher which would enable faster/further travel for far less energy use. The energy density comparison is predicated on using that energy in exactly the same way with the same efficiencies. If long distance flight becomes 100x more efficient then the density difference isn't a problem.