From what I know and learned from this site, a striaght winged airplane (no matter whether it is a laminar flow wing or not) would at the least shake itself to pieces at that speed and probably fall out of the sky. Also, as I have learned from this fine site, a propellor goes "supersonic" from the tips towards the hub. And (another member can correct me if I am wrong) once the prop goes supersonic it no longer can grab the air to propel the airplane. Lastly, The Hinton clan have been trying (unsuccessfully) to take a much modified P 51 through the 585 mph barrier. Lastly, what RR engine could develop the power to achieve this feat? The only one I personally know of that had the power to come anywhere close to achieving this is the Chrysler Hemihead aircraft engine that never went into series production. Lastly, it has been widely quoted that the ME 262 had a top speed of 540 mph. If that is the case, why did the P-51's in Europe have such a hard time battling the 262's? A 600 MPH Mustang would have eaten the 262 for breakfast.