Not fundamentally more efficient, UNLESS in a Hyperloop-like vacuum tube (as this one is). Let’s consider at near sea level. At near sea level, the drag at tho

Not fundamentally more efficient, UNLESS in a Hyperloop-like vacuum tube (as this one is). Let’s consider at near sea level. At near sea level, the drag at those speeds is absolutely brutal. Airplanes win, although they’re harder to electrify. If you extrapolate current Maglev designs to 1000km/h, for energy consumption per passenger mile is about 0.5kWh/(passenger-mile). Airplanes are on the order of 100mpg/passenger, or 0.33kWh/(passenger-mile) even with the relatively low conversion of chemical energy to mechanical in a jet engine. An electric aircraft could get about 0.1-0.2kWh/(passenger-mile) with the same airframe if the battery chemistry is appropriate for that flight length. Improve the airframe, and <0.05kWh/(passenger-mile) is possible. Length of electric flight is limited, but 1000km is possible with current chemistries. America’s near-term HSR routes are on the order of 500km, so electric flight is feasible. This is why “Hyperloop” (or vacuum trains generally) are and were a good idea at the high end for high speed rail, in spite of all the mocking that Elon Musk incurred for the idea (which he/SpaceX popularized and funded student competitions for, although the idea is an old one). Otherwise airplanes win on efficiency.