
Mars Helicopter to Fly on NASA’s Next Red Planet Rover Mission - polar
https://www.nasa.gov/press-release/mars-helicopter-to-fly-on-nasa-s-next-red-planet-rover-mission
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Communitivity
Creating that helicopter must have been a very interesting and difficult
challenge. Lift L for rotor blades is calculated by the equation L = ½
ρ(v^2)ACL, where ρ is atmospheric density. v is the speed of the blades moving
through the air (roughly speaking). A is the total blade area. And CL is the
coefficient of lift, which is determined by the angle of the helicopter, if I
understand it right.

Mars' atmospheric density at surface averages .087 psi, roughly .06% of
Earth's average (14.69 psi). (source:
[https://en.wikipedia.org/wiki/Atmosphere_of_Mars](https://en.wikipedia.org/wiki/Atmosphere_of_Mars)
)

That means right off the bat you're going to need to increase the speed of the
blades squared times the total area of the blades (i.e., (v^2)A) by a factor
of ~1666.66 just to get the same lift on Mars that you would on earth.

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polar
JPL published a video about the idea three years ago:
[https://www.youtube.com/watch?v=vpBsFzjyRO8](https://www.youtube.com/watch?v=vpBsFzjyRO8)

