Self-explanatory. Jet engine with propeller attached to it.

Well, some turboprops can provide a bit of thrust from the engine. And there are two types. One has a gearbox connected to the intake fan. The other one has a turbine connected to the exhaust (like a turbo in a car). Only the first type can provide power using the exhaust, the second draws too much energy from it for the prop. They differ because they're better at driving huge, high pitch props at low RPM, as opposed to piston engines, which are better at driving smaller/lower pitch props at high RPM. Torque vs horsepower, essentially. And turboprops can actually be more efficient...

Hrm. I'll consider it as I can see needing the power, but seeing as how we currently have very few people modding planes and even fewer needing turboprops, I'm putting it on the backburner.

Well, you'll be "glad" to hear I'm considering doing a turboprop as the next plane I do.

After further consideration, I believe the current physics system works well enough to support a turboprop with either an aircraft or jet engine. We can re-visit this when actual "turboprops" get in, but I suspect we won't have to.

Need a bit more explanation as to how these differ from regular props. They don't provide thrust through the engine from what I can tell, so they're still a propeller-based engine, which is what the current engines are.