>>1087472With regards to engines alone, pure turbojets are best for supersonic flight regimes, as they can take advantage of ram effect, which turbofans cannot.
>>1087609>not an option and not debatableNO. Efficiency is a key component, but it is not the only factor that must be considered. Money is the only thing an airline sees, as it is a heavily regulated business with lots of expenditure. Time is money to some people; I guarantee you there are people willing to pay to get from New York to London (or wherever for that matter) as fast as possible, even with a hefty price tag. If it is profitable they will invest in the technology.
It is certainly possible, but the time and money required for supersonic transport research, both engine and airframe, is a hard pill for people to swallow. The only reason that conventional subsonic aircraft look so good in comparison (from a numbers standpoint) is that they have been developed continuously since the 1950s and there is an existing market established for it. Thankfully both NASA and several private companies don't share your pessimistic appraisal of the concept.
