Originally Posted by
rickair7777
This is a correct rough approximation.
It does not however account for cargo carriage, which is significant on larger jets (non-RJs).
It also does not account for indirect environmental and societal costs of driving for days on longer trips. Also does not account for the difficulty involved in driving across oceans, or desolate wastelands.
no doubt there are many other factors and overall air travel generates many efficiencies lost on surface transportation. but just a blanket ststment saying planes have better MPG than cars by using per seat on a plane vs per vehicle on a car can be a flawed logic; assuming you are traveling with your family and not alone