As someone who travels cross-atlantic semi-occasionally my price threshold for a 50% shorter flight is 25% increased cost. This is coming from a relatively well off middle-aged software engineer.<p>It is hard to think that this tech will ever be common besides a few "high status" (NY->London) routes like the concord was. It is my understanding that fuel costs increase as speed increases so there is no way this could ever be cheaper than non-hypersonic flights. But of course there is a market even if it is very limited, just like there was one for the concord. I expect this tech might displace some of the private plane market.<p>To me it seems more likely that we will see short-haul smaller electric aircraft take over for even cheaper costs with more stops along the way. Think like NY -> Açores -> London or LA -> Hawaii -> Japan.<p>edit: reading about this it seems the fuel-efficiency calculation is not as simple as I thought, there are some savings to be had in fuel by going above sound-speed. It seems the lowest fuel-efficiency happens at just below speed of sound. I am no expert in the subject though.