The purpose of an afterburner is to provide a temporary increase in thrust, both for supersonic flight and for takeoff, as the high wing loading typical of supersonic aircraft designs means that take-off speed is very high. On military aircraft the extra thrust is also useful for combat situations. This is achieved by injecting additional fuel into the jet pipe downstream of the turbine. The advantage of afterburning is significantly increased thrust; the disadvantage is its very high fuel consumption and inefficiency, though this is often regarded as acceptable for the short periods during which it is usually used.
Afterburner Run on a Jet Aircraft