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JPL's Plan for the Next Mars Helicopter

spectrum.ieee.org

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Re: JPL's Plan for the Next Mars Helicopter

#21

Post by spullara »

zabzonk wrote: post #13
gambiting wrote: post #10

Earlier quoted context omitted.

Earth also doesn't have any nuclear powered rovers driving on the surface and yet Mars does. Might have something to do with the fact that the risk to humans on Mars is slightly lower than on Earth,no?

Yes, but also that you can't refill with gas on Mars. And of course we do have nuclear powered vehicles cruising around on Earth. We have also had nuclear powered bombers and cruise missiles, none of which were exactly successful, but not even the US DoD has ever suggested a nuclear powered helicopter. It would be a great introduction to our relationship with Mars if one of the first things we ever did was to spill p…

Not that likely even in the event of a crash.

https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_ge...

"This incident resulted in the NASA Safety Committee requiring intact reentry in future RTG launches, which in turn impacted the design of RTGs in the pipeline."

Re: JPL's Plan for the Next Mars Helicopter

#22

Post by trothamel »

dogma1138 wrote: post #14

Wouldn’t an airship be a more viable option for a long term mission on Mars?

Airships seem somewhat vulnerable to the weather, in practice, as they're always flying. A nice thing about a helicopter is you can land, and it's a station until you take off again.

Re: JPL's Plan for the Next Mars Helicopter

#24

Post by mikepurvis »

trothamel wrote: post #22
dogma1138 wrote: post #14

Wouldn’t an airship be a more viable option for a long term mission on Mars?

Airships seem somewhat vulnerable to the weather, in practice, as they're always flying. A nice thing about a helicopter is you can land, and it's a station until you take off again.

I don't think we know too much at this point about how Ingenuity will survive dust storms— I see a reddit thread on this but not much else:

https://www.reddit.com/r/space/comments/lo6k73/what_will_hap...

If there was a dedicated mission for a much larger helicopter, it would obviously be important for it to have a story for weathering these things.

Re: JPL's Plan for the Next Mars Helicopter

#25

Post by BotJunkie »

verytrivial wrote: post #23

Why do so many website disable zoom? Why?!

If you're looking for a better resolution version of the concept image, as far as I know there isn't one. The original is here, and it's not great: https://www-robotics.jpl.nasa.gov/tasks/showBrowseImage.cfm?...

Re: JPL's Plan for the Next Mars Helicopter

#27

Post by wongarsu »

gambiting wrote: post #10
zabzonk wrote: post #7

Earlier quoted context omitted.

Do you see any nuclear-powered aircraft flying around on Earth?

Earth also doesn't have any nuclear powered rovers driving on the surface and yet Mars does. Might have something to do with the fact that the risk to humans on Mars is slightly lower than on Earth,no?

French EVs are over 70% nuclear powered. We just keep the nuclear generators stationary and use battery buffers in the car to save weight.

You might argue it's about risk, but that didn't seem like such a huge deal when we tried to make nuclear cars and planes back in the 50s. RTGs are just incredibly inefficient, and properly shielded fission reactors are incredibly heavy.

Re: JPL's Plan for the Next Mars Helicopter

#28

Post by cratermoon »

scrumbledober wrote: post #8
cratermoon wrote: post #4

Earlier quoted context omitted.

Much too much mass. The atmosphere on Mars is 6.518 millibars. Look to the structure and mass of terrestrial birds for a guide.

terrestrial birds which would all have far too low of a lift to weight ratio on mars to ever have any hope of flying. The current mars helicopter is pretty incredible

Yes, to be pedantic about it, but I didn't say "send birds" or "do exactly what birds do", I said to look to them for ideas. Eliminate every extra gram, optimize aerodynamics and control for the purpose (c.f. owls vs. quail vs. hummingbird vs. woodpeckers) and go from there. Don't try to build a flying machine around power source that is essentially a hunk of dense metal.

Re: JPL's Plan for the Next Mars Helicopter

#29

Post by CapitalistCartr »

zabzonk wrote: post #7
srcmap wrote: post #3

Wonder if it is practical to design Helicopter with nuclear battery similar to the rover....

Do you see any nuclear-powered aircraft flying around on Earth?

We developed them during the Cold War. The issue was the massive release of radiation behind them. Don't fly it over your own country. But they can cruise for days!

Re: JPL's Plan for the Next Mars Helicopter

#30

Post by dogma1138 »

trothamel wrote: post #22
dogma1138 wrote: post #14

Wouldn’t an airship be a more viable option for a long term mission on Mars?

Airships seem somewhat vulnerable to the weather, in practice, as they're always flying. A nice thing about a helicopter is you can land, and it's a station until you take off again.

The weather isn’t that of an issue due to the thin atmosphere. You can land an airship by compressing the lifting gas into a liquid. If you can get enough power reserve at least to do that.

The main issue would be the size of the balloon but honestly if we can make some origami rigid airframe a vacuum airship might actually work.

At that point controlling buoyancy is also less of an issue from a power perspective since you don’t need a large power reserve to land, and when you are on the ground you can wait until you have enough power to create sufficient vacuum in the airship.

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