TL;DR
Flying faster than sound, over oceans and maybe one day over land, could come back, and the one company building a supersonic passenger jet just hit a milestone, though not in the sky. Boom Supersonic says it finished the first core of "Superpower," a 42-megawatt power turbine built from the engine it designed for its Overture airliner, on Oct. 22. The turbine is meant to make electricity on site for data centers, a market that is buying now. That could give Boom money and real-world hours on its engine's core while the airplane catches up. The catch: the turbine's first customer cancelled in September, every number here is Boom's own, and Overture has yet to fly a single test aircraft. Meanwhile the rules that could reopen U.S. skies to faster-than-sound flight are moving, and NASA's quiet supersonic jet is flying regularly.
Below the line, for paid subscribers: The full story: where it stands, how we got here and what's dated next; our Odds board on 6 milestones, starting with "A supersonic airliner carries paying passengers over U.S. land"; our labeled speculation on what it adds up to; and every source.