Supersonic aircraft Supersonic aircraft A supersonic aircraft is an aircraft able to fly faster than the speed of sound (Mach number 1). Supersonic aircraft were developed in the second half of the twentieth century and have been used almost entirely for research and military purposes. Only two, Concorde and the Tupolev Tu-144, ever entered service for civil use as airliners. Fighter jets are the most common example of supersonic aircraft. The aerodynamics of supersonic flight is called compressible flow because of the compression (physics) associated with the shock waves or "sonic boom" created by any object travelling faster than sound. Aircraft flying
Speed of sound Speed of sound The speed of sound is the distance travelled per unit time by a sound wave as it propagates through an elastic medium. At , the speed of sound in air is about 343 meters per second (1,234.8 km/h; 1,125 ft/s; 767 mph; 667 kn), or a kilometre in or a mile in . It depends strongly on temperature, but also varies by several meters per second due to which gases are present. The speed of sound in an ideal gas depends only on its temperature and composition. The speed has a weak dependence on frequency and pressure