Two of the biggest names in aerospace, Boeing and Lockheed Martin, have both submitted designs to NASA for possible supersonic jets--like the Concorde, but without the noise.
The designs are not entirely dissimilar from the Concorde, with very long and narrow bodies and possibly a dipped nose, but also have a few key differences the designers and engineers hope will lessen the supersonic boom the Concorde created.
The Concorde's supersonic boom was created when the shock wave from the plane's high speed collided with the ground. It was so loud that the Concorde was actually forbidden from flying over land in the continental United States, with rare exceptions.
Designers and engineers have been working for years on a solution to this problem. Both the Boeing and Lockheed Martin designs place the engines on top of the wing, rather than underneath, hoping that the wing itself will reduce the volume of the boom. Lockheed Martin also has an odd, inverted-V-shaped tail that might lessen the boom through airflow control.
Interested? Read more about NASA's efforts to reduce the sonic boom of supersonic jets on the agency's website.