What would a formula look like for calculating the rotor blade tip speed on a helicopter? I.e. a blade on an R44, or a blade on a micro helicopter that's only 360mm. -
![drag - At what rpm does the tip of a 54" propeller start to incur mach losses? - Aviation Stack Exchange drag - At what rpm does the tip of a 54" propeller start to incur mach losses? - Aviation Stack Exchange](https://i.stack.imgur.com/0cdls.jpg)
drag - At what rpm does the tip of a 54" propeller start to incur mach losses? - Aviation Stack Exchange
![Theoretical and computational investigations of the optimal tip-speed ratio of horizontal-axis wind turbines - ScienceDirect Theoretical and computational investigations of the optimal tip-speed ratio of horizontal-axis wind turbines - ScienceDirect](https://ars.els-cdn.com/content/image/1-s2.0-S2215098618301381-gr1.jpg)