[BotJunkie]

I interviewed Bob and wrote this article, so I can answer a few of these.

I think JPL's idea is that MSH would be a dedicated helicopter mission, rather than piggybacking on some other mission, so it wouldn't be eating up the mass budget of another lander or rover.

Similar to Ingenuity, the flights would be autonomous but the science wouldn't be. MSH would fly up to a cliff face (or whatever), take pictures, land, ask Earth where to sample, and then make a second flight to do the sampling.

MSH would be able to communicate with orbit directly and would not need rover or lander support.

[akiselev]

> MSH would be able to communicate with orbit directly and would not need rover or lander support.

Does that mean it wouldn't be powered by an RTG like the last few missions? Or do you just mean that the MSH will have its own comms independent of a supporting rover/lander?

[BotJunkie]

JPL has run the numbers on this as part of the engineering study. The solar panel shown in the concept image (in the center) charges a battery that gives MSH a 10km range or 5 minutes of hover time after charging for a day. It would have its own comms that could reach orbit.

[akiselev]

Ooof that's hard to swallow :(. Would the MSH be so productive that it makes up for the limited operating time? Is mission planning so meticulous that it would be a bottle neck anyway? What about winter?

Whats the power budget for instruments during/after flight?

[minitoar]

For reference the rovers can do 100 meters a day. 10km in one day is huge.

[XorNot]

Yeah I was going to post this too: the range of a helicopter like that is massive. Well into the "find an interesting feature and follow it" range.

[BotJunkie]

This is all the next step. If they end up putting together an actual mission proposal, they can factor in power budgets for specific science instruments, sun angles and seasonality at the landing site, etc, but they're not quite there yet.

Not sure what you mean by limited operating time, though- if you mean that MSH has to spend 50% of its time charging, that's true, but relative to a rover, it can travel so much farther and faster that JPL is arguing it more than makes up for it.

[MichaelZuo]

The rotors would have to be massive to lift 30kg, that may be a stumbling block as it’ll require folding and so on. Seems like it would need a lander at least for recharging right?

[arhpreston]

If you're interested in the details of what goes in to developing rotors for a helicopter for an atmosphere we've never built in before you should check out this talk: https://doi.org/10.52843/47ly7q

[MichaelZuo]

Thanks! In scaling up the fragility of the material seems very likely to be a big factor, cube-square law and so on. I wonder if there’ll be physical testing of proposed designs, are there even near-vacuum wind tunnels?

[arhpreston]

A lot of that talk compares theoretical results with experiments in a low-pressure wind tunnel (see e.g., the slide at this point https://cassyni.com/events/6GYLBKG5pBd4su8dm9A9FB?t=255.0s for a reference).

It's quite a simplistic (2d) setup however. I'm not aware of any more complex experiments.

[BotJunkie]

You can see how the whole thing would fold up in the linked article, there's an image from the white paper that shows MSH fitting into the same size aeroshell Mars Pathfinder used. It would run on solar power and recharge itself, just like Ingenuity.

[MichaelZuo]

Thanks, for some reason I had a brain fart and thought it’s one giant rotor.

[amelius]

Also, the rotors would blow away dust on the landing site, which may be a problem if you want to research dust, but may be an opportunity if you want to see what's beneath it.

[XorNot]

Hopefully by the time this thing is ready to be built SpaceX have the Starship flying. Getting payload to Mars is going to get a lot cheaper if they hit even half their goals (even if we're just launching the rocket that goes to Mars on top of a Starship).

[ragebol]

Imagine deploying 100 of these helicopters deployed from a single Starship.