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.

The Turbomeca Palouste is a French gas turbine engine, first run in 1952. Designed purely as a compressed air generator, the Palouste was mainly used as a ground-based aircraft engine starter unit. Other uses included rotor tip propulsion for helicopters.