[Tuxer]

Well if you're investing a lot in newer plane tech, yeah I'd like them to think about the externalities of what they do and find alternative solutions. For example on high-flying airliners (I expect this plane to, like concorde, fly around FL550) you could potentially go with a hydrogen propulsion at least in cruise, since the outside air temperature wouldn't result in H2 boil.

[njarboe]

Once a new supersonic jet is built and flying then these changes can be done, by others if necessary. Don't you think building a supersonic jet is a hard enough problem already? We are still burning oil in 99% of cars and you are worried about burning oil in supersonic jets?