They can, that's how the Concorde used to fly, but it meant that a flight from London to New York was only able to be done at supersonic speed for something lik

They can, that's how the Concorde used to fly, but it meant that a flight from London to New York was only able to be done at supersonic speed for something like half the trip (measured in time). The aircraft was also incredibly inefficient at subsonic speeds because the aerodynamics were all optimized for much faster flight https://simpleflying.com/concorde-long-distance-over-land/ https://simpleflying.com/concorde-long-distance-over-land/ https://www.youtube.com/watch?v=E2_AzIktybM https://www.youtube.com/watch?v=E2_AzIktybM