[Kngkyle]

The additional fuel and structure required to exceed the speed of sound has made ~550mph the 'sweet spot' for commercial aviation. Not to mention the sonic boom restricting supersonic speeds to just over the oceans. I agree though, it's a bit frustrating that we haven't engineered our way around these problems. It is certainly possible - it's just nobody who can do it (Boeing, Airbus) want to bet their entire company on it, since it would easily cost over $30 billion. It would be cheaper to send humans to Mars.