"A gyro’'s primary attribute, its ability to safely fly low and slow, makes it an ideal vehicle for chasing feral hogs around Florida bayheads but its inherent inefficiency – wings going 500 mph while the rest of it goes 50 mph, makes it as useful as an item of transportation as a rowboat." – C. Beaty

OK, after reading that, I decided to do a quick calculation of how many mph the tips of my 28' rotor are going at any certain rotor rpm. The interesting coincidence is that, for a 28-ft-diameter rotor, mph is almost exactly the same number as rrpm!

28π (feet per rev) x 60 (min/hr) = 5278 ft (per rpm per hour). There are 5280 ft in a mile, for those non-US folks reading this. So when I have 325 rrpm (typical), my blade tips are going just about 325 mph.

OK, after reading that, I decided to do a quick calculation of how many mph the tips of my 28' rotor are going at any certain rotor rpm. The interesting coincidence is that, for a 28-ft-diameter rotor, mph is almost exactly the same number as rrpm!

28π (feet per rev) x 60 (min/hr) = 5278 ft (per rpm per hour). There are 5280 ft in a mile, for those non-US folks reading this. So when I have 325 rrpm (typical), my blade tips are going just about 325 mph.

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