I guess the current long routes would not work, but apparently airliner fuel efficiency improved by almost exactly this much since 1980 (https://www.greenaironl

I guess the current long routes would not work, but apparently airliner fuel efficiency improved by almost exactly this much since 1980 (https://www.greenaironline.com/news.php?viewStory=684 https://www.greenaironline.com/news.php?viewStory=684), so it still seems that's the era we'd go back to...