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A propeller is a spinning wing. Supersonic wings work. So, provided that the blades are made wide-chord and thin like supersonic wings are, with a supersonic airfoil, can they not power efficiently a supersonic aircraft?

Abdullah is not an Amalekite
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    See: Why are there no supersonic propeller driven aircraft? –  Dec 09 '19 at 11:01
  • "1.The supersonic regions at the blades create tremendous forces which will tear the propeller apart. Thus the design needs to be such that these forces can be mitigated. This is also the case for jet engines, which is why the ducts are designed such that the airflow into the engine is slowed down to subsonic speeds." 1.even supersonic wings experience tremendous forces. 2.propfans are a thing and may have supersonic blades, yet do better than turbofans. The second reason stated is irrelevant. – Abdullah is not an Amalekite Dec 09 '19 at 12:08
  • Supersonic wings are much wider (root chord), and therefore can withstand the forces (the higher the aspect ratio, the weaker the blade/wing). And you don't need propfans for emphasis because the tips of the fans in turbofans are already supersonic. Now, you may want to edit the main question to highlight those issues, to get an answer that is on point. –  Dec 09 '19 at 12:14
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    In case someone gets this misconception, I'm not asking why supersonic propellers don't exist, rather, what it would be like if they did. (I'm writing this here because this is where people will post links to "similar" questions) – Abdullah is not an Amalekite Dec 09 '19 at 12:40
  • One word: Thunderscreech. – Zeiss Ikon Dec 09 '19 at 13:25
  • Perhaps getting a little carried away with question trimming and pruning here. Some good answers out there, and supersonic props do work, they are just very noisy. Decibel limit regulations stopped the prop-fan for now. And enclosing a very rapidly rotating unit for failure containment should keep the fan jets going for a while. But, importantly, the faster you go, the more a prop blade needs to be pitched to get optimal AOA. A little vector analysis shows you get less and less forward thrust the faster you go. As some point it isn't worth the drag. – Robert DiGiovanni Dec 09 '19 at 15:48
  • If you want to know just how noisy a supersonic propeller can be, read this artcle about the Republic XF84H. The engine could be heard 25 miles away, and ground crew suffered headaches, nausea, incapacitation and in one report, a seizure.The USAF ordered it off base because the noise was too disruptive. – CatchAsCatchCan Dec 09 '19 at 21:58

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