utilizing supersonic flow wherein the jet or stream may be rapidly and accurately switched between a plurality of stable positions with respect to the axis of switch 10 in actual practice switching rates in excess of 100 cycles per second have been achieved the stream from switch 10 discharges into a thrust augmentor indicated generally at 24 in the disclosed embodiment augmentor 24 includes a bell mouth portion 26 a straight or mixing section 28 and a diffuser section 30 the design of augmentor 24 is in accordance with techniques well known in the art in combining augmentor 24 with switch 10 care must be taken to insure that the deflected primary flow from switch 10 does not impinge directly against the wall of the augmentor in operation as depicted in the drawing the stream exiting from the switch 10 will be 34 switched 34 at a sufficiently fast rate so that discontinuities in flow will occur these flow discontinuities result in a rarefaction of the air behind each pulse or slug of primary gas and a compression of the ambient air ahead of each gas pulse the pulses of primary gas effectively push the ambient air i e the pulses induce movement of the ambient air thus producing a condition where more secondary air can flow into the rarefactions behind each primary gas pulse the rapid switching of the primary.