I live in the UK and caught a train to London then a Eurotunnel train to Paris and it was probably quicker and easier when you account for time spent in departures and going through airport security.

It seems that the cost of an additional passenger on a train is almost zero, so why do trains not attempt to reduce per-ticket prices to increase capacity and become more competitive against low cost airlines?

In your example, the train from London to Paris in my experience has almost always been nearly triple the cost of a flight.

It is. But the cost of the first passenger is massive.

Think of all these rails (and the terrain under it you have to pay a hefty price for), all the bridges etc.

You mention the Paris-London train, just the tunnel did cost $21 billions, add the high speed rails before and after it and you are probably at close to $40 billions in infrastructure before the first train can do the trip.

Trains are orders of magnitude greener than planes, but unless you massively tax planes, or massively subsidize trains, they'll always be more expensive than planes.

The east coast is already covered by an excellent train line. That line could be made faster to be more competitive but it already handles far more passengers than air.

Now let’s look at some other popular routes.

Chicago to LA? 2,000 miles. That would take around 10 hours nonstop on the fastest high speed train. Make that even worse for New York to LA, and you can bundle in destinations like Denver, Las Vegas, Seattle, San Francisco, etc into those long distance routes that simply don’t make sense from an eastern city.

How about popular vacation routes, like Boston to Orlando? 1300 miles, so that’s at least 7 hours assuming the train never stops.

The new-ish Amtrak CEO is correct to focus on intercity routes that are between closely packed cities. The US does need more train routes similar to the Hiawatha Service or Northwest Corridor and they need to go faster.

But even this type of buildout will be limited when you consider the size of cities in the US. If you fly from Indianapolis to Pittsburgh you’ll be on a 50 seat jet or you’ll transfer to somewhere like Detroit. What sort of train carrying 50 people will be anywhere close to economically viable?

Sure, we could use some rail connection between something like Houston and Dallas but then those passengers will also have to rent a car or use a taxi frequently at their destination. At that point you are competing with individual driving.

Back to the Hiawatha Service, if I’ve got two people in my party it’d be cheaper to drive and possibly even Uber the entire way if I had four people in my party.

The leader in high speed rail, China, has nearly ideal conditions to work with. They have huge populations concentrated in dense urban areas with low car ownership. They have almost all major cities concentrated on on one coast. They have low labor costs and a centralized government structure that doesn’t have to consider property rights or environmental impact when building out infrastructure.

I'm not even considering the delays because of weather, technical, etc.

Trains don't have as much potential for being delayed (train schedules have a lot less variance because the track is pretty much fixed and the timetables too), and they take you right from the city center to the destination's city center.

Comfort doesn't compare either, you don't have to pay extra so you can actually sit down like a human being and retain your dignity.

And if the trains were electric instead of diesel like they are in the US, I wouldn't be surprised if it was also cheaper than flying.

As a counterexample to China, Switzerland has an amazing rail network. Trains going from anywhere to anywhere, comfortably, reliably, quickly, and multiple times a day. And yet, the country is very mountainous, and has lots and lots of smaller cities.

Why we've to damage our planet so much just to see some locations?

It’s not difficult to imagine a hybrid system at some point in the near future, and/or other ways of reducing the carbon footprint. Focus on those positive things, rather than “this will never be completely green, so why bother?”

You are putting words in my mouth, I never said that.

The industry has been reducing emissions per mile pretty much since it was founded. Looking at that graph I posted it is having the opposite effect to what we want. Jevon's paradox and all that.

My personal solution was to stop flying, I haven't got on a plane for 19 years. I'm not sure that is palatable to most people here though, it certainly isn't to the airline industry.

The article mentions the delta wing design may save 20% on fuel consumption. However those gains are completely swallowed by the traffic increase which is about +30% every 10 years if I remember correctly.

The target for 2050 is completely unrealistic, considering the traffic increase and the long cycles of the aviation industry. It may be achieved with hydrogen, assuming it can be produced in large enough quantities with renewables.

"should we therefor not even attempt it?"

Oh they certainly want to look as if they were trying to reach there objectives ... for the moment it is business as usual. The production of conventional, kerosene powered planes has never been so high and still increasing.

The heavier a plane is, the more fuel it needs. But fuel has weight, too, which means you need even more fuel! Reducing fuel consumption translates to exponential operational savings.This is also why planes with batteries are problematic: batteries store much less energy per kg than fossil fuel. I doubt that the increased efficiency in going electric is going to offset the extra consumption due to the increased weight.

Even if they reduce emissions by 50% by 2050, flying will still produce ~5 more times CO2 than taking the train. And guess, what? The railway industry is also working to reduce emissions and with trains there's just so much more you can improve with much less investment.

By 2050, aviation might very well produce ~20 times the emissions of railways, even though it has halved its emissions.So, with our current knowledge, the best way to reduce aviation emissions is...taking the train.

Train is better for short hops between highly populated areas, but not so much between islands with 10k peoples. Many short flights are between places where only other option is car + many hours on ferry, and for them an electric plane would be perfect

That means they’d probably cost more than commercial jets, because the crew is being paid for a longer period of time.

It also seems like jets can fly in far more inclement weather than blimps, but I’m no expert in that.

Also, the Hindenburg went at 100+ km/h in the 30's, we're already using many kinds of vehicles that go at similar speeds and don't cost more than commercial jets. Hopefully we could beat the 30's technology in speed, that's just the lower bound.

edit: also, correcting my terminology, I should have talked about "rigid airships" instead of "blimps" apparently - blimps are like balloons with little engines, and the Hindenburg & modern credible air travel blimpy looking designs are "rigid airships".

In a world in which heavier-than-air flight becomes less affordable, there might be some niche uses. In general, my sense is that lighter-than-air craft are simply too close to the limits of potential engineering and materials.

The question is not "how can we keep our air travel habits?" after all.

Air travel has been transformational, fast, reasonably convenient, and cheap. It's also been an accident of geohistory, in many regards. The coming / current fuels transition will raise the costs of many things, transport included, and air transport most especially. One of the lessons of history is that the consequences of costs falling, as many have through the industrial revolutions, have subtle and profound influences, mostly unanticipated by those who first started down specific technical pathways.

My sense is that rising costs will operate similarly. We'll have much of the knowledge and technical understanding achieved over the past 200 years, but we'll see costs rising or capabilities falling in many domains. And that will have profound and subtle ripple effects.

Small aircraft may be possible, and perhaps slow airships, but the era of mass bulk human transcontinental transport, quite probably not so much. Or possible, but at prices at some multiple of today: 2x, 10x, 100x, 1,000x. Or transoceanic travel of 1-3 days, rather than 6-18 hours.

Getting back to airships: there are only so many materials available. An airship requires some sort of frame, some sort of lifting gas containment, motors, an energy source, and passenger or cargo facilities. Even excluding hydrogen as a lifting gas, they've proved expensive and dangerous. Vehicles such as LEMV / Airlander 10 are not strictly rigid, but is in part supported by pneumatic pressure. The craft itself was written off after coming loose from moorings in high winds.

Top speeds will be on the order of 160 - 240 kph, rather than 1,000 kph for jet aircraft. Flight levels will likely be < 1,000 meter -- Hindenberg cruised at 300m, though often much lower. That's well into weather, which airships handle poorly. LEMV had a requirement to operate to 20,000 ft (6,000 meters), though it only reached 3,500 ft (1,000m) in testing.

I've watched and read breathless accounts of an airship revival for decades. To date they've failed to meet promised capabilities.