You raise good points, but let's also consider that: -planes travel a lot of miles very quickly. MPG is a fine number, but we should also look at something lik

You raise good points, but let's also consider that: -planes travel a lot of miles very quickly. MPG is a fine number, but we should also look at something like total emissions per year of average use. -planes emit around 3% of the global carbon total but serve only around 15% of the global population, unlike most industries. I'm not going to stop flying anytime soon, but let's not kid ourselves about the impact our collective lifestyle has on the rest of the world. Also worth mentioning that measures like carbon taxes, while having many problems, neatly solve what to optimize for when fighting carbon emission. Scale is automatically baked in.