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by ortusdux 22 hours ago
Here is a good list of 'fuel per seat (in mpg)' numbers for various airplane configurations and flight durations: https://en.wikipedia.org/wiki/Fuel_economy_in_aircraft#Examp...

The total average across the industry in 2018 was between 67 and 81 mpg. Modern planes are in the 100-120mpg range.

2 comments

The issue is that we are enabling people to travel long distances too cheaply.
And above all too quickly. Per kilometer, flying is roughly as polluting as driving, but nobody would think to drive across a continent to go to the beach.
Yes they would. That's why we get massive queues for alpine crossings during European holidays – German and Dutch tourists trying to get to the beaches in Italy.
What about short distances? Why is it cheaper to fly Berlin-Stuttgart than to take a train? it makes absoutely no sense.
The costs are pretty evenly split between: 1) Maintaining track 2) Buying/leasing/maintaining trains 3) Staff

The single best thing you can do to drive down train cost is to put more people on each train.

Based on these sources: https://www.statista.com/chart/20169/gb-rail-fare-spending-b...

https://transport.ec.europa.eu/document/download/f5c82d86-23...

Trains are expensive because the track is 99.9% empty.

If you could fill a train track as much as a road is filled, it would be very cheap

Track utilisation is limited by a number of factors, including headways, much of which is governed by stopping distance.

I believe a general minimum practical headway allows about 10--12 trainsets per hour on a given track. At 400 passengers/trainset, that's roughly 4,000 to 4,800 passengers/hour, per track.

That compares with about 1,500 vehicles/hour per highway lane, or about 2,550 passengers/hour at the U.S. average of 1.7 passengers/vehicle.

I've seen some suggestion that headways could be reduced to 3--4 minutes, or 15--20 trainsets/hour. I know that some urban rapid transit systems (e.g., BART in San Francisco) achieve this, but only on a small section of the system (Colma to Oakland, transiting downtown SF, IIRC). Train speeds there peak at 70 MPH, and I believe are much slower for most of this portion of track.

Some urban subways have 30 second headways.
Yes, let's make things more expensive, cause we experts know best. That poor guy that needs to attend a family funeral, he's a loser that should stay home. Inflation for the Win!
Ideally making polluting activities more expensive would go hand in hand with reducing inequality - so people could still afford needs like going to a funeral. A great example of this is Canada's Carbon Fee & Dividend system.
Does he really "need" it though ? For thousands of years people didn't travel shi fast to attend funerals (they only did it locally), where they less happy about it ?
and according to the article the last record was 200k planes per day on june 29 2025, while july 23rd had more than 280k - so while efficiency may be going up (how many of those 280k planes are in the modern 100-120mpg range?) total flights are as well. Result: total emissions are steadily increasing.