The Spike S-512 is a projected supersonic business jet, designed by Spike Aerospace, an American aerospace manufacturer firm based in Boston, Massachusetts.

A supersonic business jet (SSBJ) is a business jet travelling above the speed of sound: a supersonic aircraft. Some manufacturers are designing or have been designing SSBJs, but none are currently available. Usually intended to transport about ten passengers, proposed SSBJs would be about the same size as subsonic business jets.