I wonder how close the estimated RPM of the blades were to the actual RPM needed for the atmosphere density it flew in.
When I first heard about this, the first thing that actually crossed my mind was the thin Marsian atmosphere followed by hmm, I wonder what the blade attack angles (min - max) are set to. Using counter rotating blades (counter rotating propellers) is an obvious solution for the thinner Mars atmosphere and was definitely need for lift (this means that less RPM is actually needed), I believe that it's around 2500RPM, actually I know that is what it is because I've read that somewhere and that would make sense for counter rotating blades.
As you probably already know, I own a number of 450 size R/C helis which I fly for fun. On the odd occasions I'll do some 3D stunt flying, so I was interested from the very beginning in the Mars heli. I've personally set most of my heli controllers to spin my 450 blades (tip speed) at around 3400 RPM, my carbon heli is set to around 3500 RPM, that is a tip speed of around 290-300 MPH.
To think that it was in December 1903 the Wright brothers made their first flight, and now in April 2021 we are flying on Mars (not just landing and taking off again), actually manoeuvring.
I found and read these...