I’m no aerospace engineer but supersonic flight, no matter how technologically advanced we become, will always remain incredibly fuel inefficient because of fundamental laws of fluid dynamics. A supersonic aircraft would likely remain a niche market, never replacing our current transonic passenger aircraft. I’m betting the tickets would be prohibitively expensive who isn’t in the top 1% or paid for by a government agency.
Apparently, there have been some ideas on how to make efficient hypersonic vehicles. The vehicle could be operating in the upper atmosphere where there’s less drag. It would basically be an inherently long haul vehicle where you’d go up do most of the trip up high, and then come back down.
Per the article the prototype was flow at around 20,000m and they’re specifically going up there for the efficiency reason. The design also has a “high lift-to-drag ratio” that is apparently helping out.
This one has some more detail, no way to confirm its veracity however. https://theasialive.com/chinas-yunxing-jet-completes-test-flight-eyes-supersonic-commercial-travel-by-2027/2024/10/29
It could all be marketing hype, but there are a couple other companies in US and UK working on similar projects.
The upper atmosphere would probably have less drag, but the lower speed of sound at high altitudes would exacerbate the issues of supersonic flight and require specialized, expensive aircraft. It may become more efficient, but I still see it as mostly a niche market.
