(21-May-2024, 09:17 PM)iFly4rotors Wrote: Regarding prop tip speed. I watched a video... will see if I can find it...
about prop tip speed. It was actually propeller physics about airplanes
and other aircraft propellers, but I think that the information applies to 
any craft with propellers.  It seems that 450 mph (I think) is the optimal 
tip speed for propellers. Increasing the speed beyond 450 mph does not 
increase the thrust. I don't know the physics behind it, just what the guy 
said. According to him, you don't gain anything by making the prop go 
faster.

If you run the numbers on any given motor's voltage (cell count) rating
and the KV of the motor, you get somewhere between 50,000 and 60,000
RPM for all motor sizes. I am guessing (but don't know for sure) that this 
puts the prop tip speed somewhere close to 450 mph for pretty much
all motors. 

I will see if I can find the video and link it in this thread. 

Later, iFly