Everyone claiming you are wrong hasn't bothered to google. Literally the first response for "overture turboprop" is a series of articles confirming what you said.

> The Overture supersonic aircraft will be powered by three turboprop engines, which includes two that will be mounted under each wing, while the third engine will be fitted at the end of the fuselage.

https://www.aerospace-technology.com/projects/overture-super...

it was never a turbo prop. You'll never get a propeller driven aircraft to supersonic speeds.

why the downvotes? the original design was trying to use 3x turboprops, and i can see articles on google about them switching to 4x turbofans after the xb-1 work

edit: see parent edit, i was wrong. you guys are pretty good at making someone with misinfo feel bad though

Not sure what you were thinking of, but they were never planning on a turboprop since that's not really possible.

I find it incredibly hard to believe that turboprop was ever on the table.

Technically yes but it would make performance worse. Props are efficient because of their large size, which allows them to push a lot of air, if you shrink it then you give up that advantage. If you had extra power left over to turn a prop, you'd want to use it to turn a bigger fan, or just leave that power in the exhaust.

As far as has ever been discovered - no, this won't work. You can think of a fan as just a prop enclosed in a housing (jet engine). A prop loses effectiveness at the speed of sound because the air passing the prop gets a high pressure shock wave that effectively makes the prop not prop-shaped, so it can't move air. Picture it as using a hammer on glass instead of pushing on glass with your hand, one works way better than the other for generating thrust. The only way (so far) to have an effective prop is to have the prop tips move slower than the speed of sound. Engine designers worked around this by slowing the air down around the prop. To do this, they moved it inside a tube. They slowed the air down so that the prop (fan) can travel more slowly, and then they heat the air behind the prop to gain excess pressure and thrust. And this is exactly what a mach 1+ jet engine does. The opening at the front of the engine forces air in, and the design of the inlet slows the air down so it is subsonic, along with a corresponding increase in pressure. Some fans (props) which are now effective because they spin at subsonic speeds compress it more, so more air can enter the engine. Then they burn fuel to heat up the air, increasing the pressure. After that they have a few more fans that run in reverse to drive the fans at the front of the engine, and finally exhaust this hotter, bigger, more high pressure air out the back of the engine to produce thrust.

So hopefully you see how your question is an interesting one, and one that has already been sorta done. Turbofans and turboprops are really quite similar, but at mach speeds only the turbofans have the right environment to be able to work efficiently. Your idea would have the prop in a supersonic air stream, which would make it effectively useless.

Edit: removed battery voltage analogy.

You might be interested in reading this stack overflow answer about differences between turbo prop, jet, and fan. https://aviation.stackexchange.com/questions/71301/what-is-t...

Another aspect to consider is changing engine characteristics for different conditions. An example is changing the structures guiding air into the engine.

https://en.wikipedia.org/wiki/Intake_ramp

Why would you do that though, instead of just running a multi-stage turbofan such as they used on the F-100 engine (F15 and F16).

"can" vs "can come up with an implementation that provides any performance benefits in any set of real world circumstances"

You could. But there's no way the efficiency and complexity penalty having props feeding fans or fans feeding props comes out ahead of "pick one and make it bigger"