I supose its obvious that it would be supersonic I guess - I think the tip of the PA28 that I normally fly is a meager 330 mph at 2500. Ho hum rather a lot less energy
I guess this opens a number of other questions - at least to me
Is there presumably a max rpm for blades after which they stop being able to 'grip' the air
Are there any variable pitch blades ?
what does -60 out mean ??
What are the fan speeds on the -400 747 ?
I could go on all night - this is facinating