2 ms·

There was at least one serious proposal for a Mars airplane: Aerial Regional-scale Environmental Survey (ARES) NASA link: http://marsairplane.larc.nasa.gov/ h

by curtis 12y ago

There was at least one serious proposal for a Mars airplane: Aerial Regional-scale Environmental Survey (ARES) NASA link: http://marsairplane.larc.nasa.gov/ http://marsairplane.larc.nasa.gov/ Wikipedia: http://en.wikipedia.org/wiki/Aerial_Regional-scale_Environmental_Survey http://en.wikipedia.org/wiki/Aerial_Regional-scale_Environme... Robert Zubrin also wrote a proposal for a nuclear powered "hopper" that would use CO2 from the Martian atmosphere: NUCLEAR ROCKET USING INDIGENOUS MARTIAN FUEL [http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov]/19920001880.pdf http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov]/199200...

Gravityloss 12y ago
Providing energy for the aircraft is a problem as well. Satellites just can keep going on, but a hydrazine fueled or battery powered plane would have a mission length counted in hours. With 1% air density and 40% gravity, I get about a factor of six speed requirement compared to earth. Have to stay below the 240 m/s speed of sound. If you had a battery plane with solar panels that could land to gather energy, then it could fly again, but the landing and takeoff might be extremely hazardous, with rocks and very high speeds. Edit: Here's a good pdf presenting calculations about these issues, it also looks at pixel smear because of the high speed: http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.78.82&rep=rep1&type=pdf http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.78....
- curtis 12y ago
  ARES was only expected to fly about an hour, which does seem pretty pointless to me. A rocket propelled Mars plane is hampered by its need to carry oxidizer as well as fuel. But it seems like you still ought to be able to get multiple hours of flight out of it -- the Rutan Voyager didn't need to carry oxygen, but on the other hand it flew for nine days. Another alternative is that you can use CO2 as an oxidizer -- Magnesium, for example, will burn in a C02 environment. Building a jet engine that runs on Magnesium is probably a non-trivial exercise, though! If you really want to build a Mars airplane, I think nuclear is clearly the way to go. I don't know how you would test it though, since we tend to frown on running unshielded nuclear reactors these days.
- curtis 12y ago
  > If you had a battery plane with solar panels that could land to gather energy, then it could fly again, but the landing and takeoff might be extremely hazardous, with rocks and very high speeds. I've also wondered if you could use beamed microwave power to power a Mars airplane. For example, you could have a solar base station on the surface, and every hour or so the airplane would circle it closely and recharge its batteries. This only makes sense if you can make the microwave rectenna on the airplane much lighter than the equivalent solar cells. An airplane that never needs to land has some definite advantages. On the other hand, an easy way of acquiring geological samples is not one of them.

by curtis 12y ago

Gravityloss 12y ago

Providing energy for the aircraft is a problem as well. Satellites just can keep going on, but a hydrazine fueled or battery powered plane would have a mission length counted in hours. With 1% air density and 40% gravity, I get about a factor of six speed requirement compared to earth. Have to stay below the 240 m/s speed of sound. If you had a battery plane with solar panels that could land to gather energy, then it could fly again, but the landing and takeoff might be extremely hazardous, with rocks and very high speeds. Edit: Here's a good pdf presenting calculations about these issues, it also looks at pixel smear because of the high speed: http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.78.82&rep=rep1&type=pdf http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.78....

curtis 12y ago
ARES was only expected to fly about an hour, which does seem pretty pointless to me. A rocket propelled Mars plane is hampered by its need to carry oxidizer as well as fuel. But it seems like you still ought to be able to get multiple hours of flight out of it -- the Rutan Voyager didn't need to carry oxygen, but on the other hand it flew for nine days. Another alternative is that you can use CO2 as an oxidizer -- Magnesium, for example, will burn in a C02 environment. Building a jet engine that runs on Magnesium is probably a non-trivial exercise, though! If you really want to build a Mars airplane, I think nuclear is clearly the way to go. I don't know how you would test it though, since we tend to frown on running unshielded nuclear reactors these days.
curtis 12y ago
> If you had a battery plane with solar panels that could land to gather energy, then it could fly again, but the landing and takeoff might be extremely hazardous, with rocks and very high speeds. I've also wondered if you could use beamed microwave power to power a Mars airplane. For example, you could have a solar base station on the surface, and every hour or so the airplane would circle it closely and recharge its batteries. This only makes sense if you can make the microwave rectenna on the airplane much lighter than the equivalent solar cells. An airplane that never needs to land has some definite advantages. On the other hand, an easy way of acquiring geological samples is not one of them.