This rendering shows the Lockheed Martin future supersonic advanced concept featuring two engines under the wings and one on top of the fuselage (not visible in this image).
NASA and contractor Lockheed Martin are moving toward a preliminary design review this summer of an ambitious plan to build an experimental aircraft that could help make overland supersonic passenger flights possible.
The Low Boom Flight Demonstrator (LBFD) project is attempting to advance beyond the old Concorde airplanes, which was restricted to supersonic flights over water because of the loud sonic boom they made.