In reply to cb294:
> but that is beside the point.
I was not arguing with your points that aircraft use more energy, but was taking issue with your assertions that aircraft are "by necessity" faster which is simply not true for any capacity from one person to hundreds, or that simply going faster uses more energy because of physics. Both totally baseless.
Aircraft are made faster because they currently are the only viable way of travel for most people for distances of over 500-1,000 miles because people want journeys shorter than 12 hours.
I also am wary of stats like those you quote if they discount average fractional occupancy as airlines then to keep that very close to 1.0, trains - over the course of 24 hours - nowhere close.
But yes aircraft use more energy when seating is maxed out elsewhere. If we didn't have them perhaps we'd have faster, less energy efficient, longer distance rail.
It's going to be interesting to see how maglev - now very real - and hyper loop - lots of momentum - eat away at the shorter range side of air travel in the next 25 years, and how hypersonic extra-atmospheric "flight" eats away at the long end off air travel in the next 50 years or so.
> transportation, and hence can only compete with trains and cars on price because the playing field is not level.
Indeed - aircraft do not have the financial or commercial costs of maintaining staggeringly massive networks and infrastructure like bridges and tunnels... Gosh darned unfair that.
Post edited at 18:49