Ramjet

A ramjet is an airbreathing jet engine with no separate compressor, relying instead on its own forward motion to ram and compress incoming air for combustion, and it works most efficiently at supersonic speeds around Mach 3, operating up to about Mach 6. Arthur C. Clarke credited the seventeenth-century satirist Cyrano de Bergerac with an early conception of the ramjet in a 1657 novel, and the French inventor Rene Lorin designed a ramjet and patented it in 1913, though he had no way to test it because no aircraft of the era could fly fast enough for it to function. The Leduc 0.10 became one of the first ramjet-powered aircraft to fly, in 1949, and because a ramjet is a compact mechanism well suited to high speed, it has since been used chiefly in missiles, and has also been tested on helicopter rotors and in artillery shells built to extend firing range.