Obsolete before it hit the drawing board and where possible, such options would be better replaced by overland VLT, very rapid rail! Particularly if MSR thorium is the preferred power source!
Alan B.

Another 'Concorde', a technical triumph but a white elephant financially.

hopefully the downsize means less warmist alarmist travelling the globe preaching to others. I doubt it though.

Excellent essay.

European multi-national airliner projects seem to have a political momentum that defies economic sense. The US (ie. Boeing) has the faster reacting economic sense. Boeing developed the 707 and then the 747 faster than Europe could react.

The US dropped Supersonic projects while UK-France blundered on with Concorde. The US were winding down 747 jumbo production [1] while Europe blundered on with the 380 jumbo.

Then, as Binoy implies, increasingly fuel efficient 2 engine widebodies are out-selling the 4 engine jumbos.

[1] I understand that Boeing ended 747 (passenger) production in the 2010s, although a few freight 747s are still being built - as at 2018 http://www.flightglobal.com/news/articles/boeing-to-keep-747-8-production-steady-for-ups-order-445447/

I wonder what the emission carbon footprint is of an A380 half-full & a twin-engined 777 fully loaded.

They'd should have further developed the L1011, technologically 30 years ahead of time & according to my friend who captained one, a breeze to fly.

A bit unfair criticism to what was a logical idea:
air traffic would increase over the decades, thus to decrease congestion at airports make a larger plane;
a larger plane is also in theory more efficient due to economies of scale: fewer crew per passenger, less wind resistance per passenger, lower airport landing charges per passsenger ;
true more airports might be built but there are always going to be main hubs such as London, Paris, Dubai, Singapore, L.A., New York, Mumbai, Beijing, etc, which are the initial and final destinations for many passengers.

I think the two causes of failure were the advent of more fuel-efficient motors, and the less than efficient management of a European Union company which apparently for political reasons, is obliged to spread assembly production over France, Germany and Spain.