Note that the Concorde B (which never happened due to the eventual low sales of Concorde A) would've had no afterburners, and been quieter for climb-out and sig

Note that the Concorde B (which never happened due to the eventual low sales of Concorde A) would've had no afterburners, and been quieter for climb-out and significantly lower fuel burn; it certainly was getting within reach during the time period of its development.