This site approaches (generically) the future – hopefully not too far - robotic flight over Mars.

http://www.robotbooks.com/Mars-plane.htm

This site explores some general concepts

http://quest.nasa.gov/aero/planetary/images.html

and this establishes some especifications (not sure if they´re designed for professional science)

http://quest.nasa.gov/aero/planetary/marsplane.html

However, I can´t find hard info. Is there any actual project being developed? Any serious schedule for such a mission? Isn’t it worth a discussion?

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Try this article. The Mars plane notion is definitely serious - one was under consideration for funding as a 2007 mission, though the Phoenix lander got the nod. (Phoenix had an advantage because they already had most of the equipment built and ready to go.)

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Thanks, ToSeek. It seems to be the best info available. As I thought, the plane will have to be very fast to generate lift in the thin atmosphere. I used to think that a Mars plane would be more like a glider, with a high aspect ratio, flying some thousand feet high or less, at low speed, in the thick of the atmosphere. Now I see they have opted for what seems to be the Martian version of a subsonic fighter jet.

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Wow, all that way for 1 hr of exploration (flight time). What kind of camera and image resolution could be achieved vs. orbiters, and how could that improvement be used to best advantage for a ~300 mile flight path?

Send that puppy right down Valles Marineris!

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Of course, there may be other approaches, for example using a rover as a refueling point, perhaps one could even use a motor system the rover could make fuel for on mars, like the entomopter suggested at the Entomopter Project.

Balloon based probes could also be a possibility, either by using pressurized gas tanks or just heated gas from the atmosphere. Perhaps oan could even use a solar balloon...

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That's pretty much what Austin Meyer, the author of the flight sim program X-Plane thought. Since X-Plane's physics models can use the atmospheric, gravity and topographic data gathered by NASA, one can actually simulate flying an airplane on Mars with X-Plane.

Needless to say, flying any sort of an aircraft on Mars would be a challenge, as Austin explains here.

How about a balloon?

Given the problems associated to Mars heavier-than-air machines, pointed by Austin Meyer over the second link Togusa provided, I think a blimp would be far less complicated.

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That's also being considered by NASA -- look here.

While somewhat less complicated than an airplane, a blimp would be just slightly more complicated than a balloon, given that a blimp needs an engine (and fuel) to provide motive thrust, which would either add to the craft's overall weight, or reduce the amount of payload that the blimp can carry.

Still, NASA is considering plans to use a blimp to explore Titan as a follow-on to the Huygens probe, as mentioned in this NASA/JPL press release. The technology could also be adapted for use on Mars.

How about swapping the approaches? A blimp for Mars and a plane for Titan. :wink:

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