Tip jet

Common card · No. 473979

A tip jet is a jet nozzle at the tip of some helicopter rotor blades, used to spin the rotor, much like a Catherine wheel firework. Tip jets replace the normal shaft drive and have the advantage of placing no torque on the airframe, thus not requiring the presence of a tail rotor. Some simple monocopters are composed of nothing but a single blade with a tip rocket. Tip jets can use compressed air, provided by a separate engine, to create jet thrust. Other types use a system that functions similarly to the afterburner (reheat) on a conventional jet engine, except that instead of reheating a gas jet, they serve as the primary heater, creating greater thrust than the flow of pre-compressed air alone; the best description of this is thrust augmentation. Other designs includes ramjets or even a complete turbojet engine. Some, known as rocket-on-rotor systems, involve placing rockets on the tips of the rotor blades that are fueled from a tank. If the helicopter's engine fails, the tip jets on...

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