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Due to the thin atmosphere generating lift on Mars is difficult at a lower speed, Flying is hard until aircraft go supersonic and then it becomes difficult to control(Ref.). The landing would not be survivable. How effective would it be to use propulsive takeoff and landing with verticle thrust assisted lift similar to the lander(cargo craft from Interstellar movie)?

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What are other possibilities for transportation on Mars?

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    $\begingroup$ Let's take the train. $\endgroup$
    – gerrit
    Jul 20, 2018 at 8:51
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    $\begingroup$ Rocket based craft, similar to the Lunar Excursion is on Module, used during the Apollo Moon landing is one possibility. Also NASA is planning to send a helicopter based craft to Mars. One issue with a helicopter on Mars is due to the thin atmosphere, the rotor blades will have to rotate much faster than they would on Earth. This also means issues of wear & tear, particularly of bearings. $\endgroup$
    – Fred
    Jul 20, 2018 at 9:04

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High rotor blade speed is a limiting factor on earth. Blade tips go supersonic. Even raindrops erode blade tips (let alone Mars grit !) The speed of sound will be lower on Mars (due to temperature) so that will set a lower speed limit. I'm not optimistic about Mars helicopters with heavy lift capacity. –

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  • $\begingroup$ in addition to the lower temperature, is the speed of sound lower also because CO2 (mass 44) is heavier than N2/O2 (28, 32)? $\endgroup$
    – uhoh
    Nov 2, 2021 at 23:32
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    $\begingroup$ Good point. Sounds like Choppers lose. I'm walking. I think the velocity ratio would be 0.87. Square root of their mass ratios. This NASA site disagrees mars.nasa.gov/mars2020/participate/sounds/… . But I think they are comparing different temperatures. Also need to take into account humidity since H2O is so light $\endgroup$
    – Woody
    Nov 2, 2021 at 23:55
  • $\begingroup$ I'm sure you're right; it will scale as $\sqrt{T/m}$. $$340 \text{ (m/s)} \times \frac{\sqrt{(273-63)/44}}{\sqrt{((273+20)/29}} \approx 234 \text{ (m/s)}$$ which is close to their ~240 m/s. I used 29 for average mass of an "air molecule" and 20 C for the 340 m/s value. $\endgroup$
    – uhoh
    Nov 3, 2021 at 0:31

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