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You should check out this: https://en.wikipedia.org/wiki/Republic_XF-84H_Thunderscreech

Yes, an aircraft employing a supersonic propeller first flew in the 1950's. It wasn't terribly efficient, but it was terribly loud .

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That's not a supersonic propeller, that's a propeller with supersonic tip speeds. A supersonic propeller is a propeller that can work in a supersonic airstream. The XF-84H had a top theoretical speed of Mach 0.9, though in testing it was evaluated to be more like Mach 0.83, and even that's disputed, with another estimate being Mach 0.7. It never achieved these speeds.

The only plane to fly with a propeller at supersonic speeds was the XF-88B, though that was actually a jet aircraft that just had a propeller on the front for testing purposes - the vast majority of the thrust was still coming from the jet engines.

> Coupled with the already considerable noise from the subsonic aspect of the propeller and the T40's dual turbine sections, the aircraft was notorious for inducing severe nausea and headaches among ground crews.[11] In one report, a Republic engineer suffered a seizure after close range exposure to the shock waves emanating from a powered-up XF-84H.[18]

Holy hell

Per TFA;

> Yes, it would be very noisy.

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