16
$\begingroup$

So I'm a Rising aerospace engineering freshman and have gotten very into the idea of learning about and figuring out possibilities of Martian Aviation. I am well aware of Mars Ingenuity and was wondering about any other plans in motion to fly on the surface of Mars.

I know of the Perlan glider which flew I believe around 80,000 feet which gives pressures around 0.02 atmospheres. This is double that of Mars but with gravity on Mars being 38% of that on Earth, it would seem that this would work on Mars. Since I think I remember reading that the glider used special wind currents to achieve this altitude which would not be available on Mars, the glider would probably not fly.

So I was wondering if it would be possible to fly a glider on Mars given its lower gravity and reduced drag. As of right now, I don't believe it could be possible to create a manned on because it would be too heavy carrying the pilot, as well as oxygen and life support, but can we and will we possibly use unmanned fixed wing glider drones for mapping terrain or the likes? Another question would be, who could I possibly get in touch with because I am quite interested and would like to learn more about this field?

ps. sorry if this post was kind of all over the place; it was my first one.

$\endgroup$
5
  • 2
    $\begingroup$ Why not put an engine in it? space.stackexchange.com/questions/2274/… $\endgroup$ Commented Aug 7, 2023 at 2:29
  • 3
    $\begingroup$ An interesting question, but a little unclear. Are you wondering whether the thermals and updraughts required to keep a glider airborne are present on Mars; or are you asking about designing any fixed-wing aeroplane that could work in Martian conditions? For the latter, there are several studies that have been conducted, for the former, I don't know. $\endgroup$ Commented Aug 7, 2023 at 3:59
  • 5
    $\begingroup$ Interesting question and Welcome to Stack Exchange! Does "fly a glider" mean drop it from high altitude and have it continuously descend until it lands say 30 minutes later, or do you mean remain airborne for hours using thermal up-currents and/or high altitude winds? Or even something like In which situations can a Dual-Aircraft Platform (atmospheric satellite) remain nearly geostationary?? $\endgroup$
    – uhoh
    Commented Aug 7, 2023 at 4:33
  • $\begingroup$ Welcome to Stack Exchange. I agree with the first answer. However: Gliders would however be most useful on a low gravity world. This would give it time to descent unpowered and charge it's battery. Then it could fire up an electric motor, ascend and repeat, extending it's flight time for science work. $\endgroup$ Commented Aug 7, 2023 at 23:42
  • 1
    $\begingroup$ Sorry for being OT, but I could not resist the obligatory XKCD: what-if.xkcd.com/30 $\endgroup$
    – Marcel
    Commented Aug 9, 2023 at 10:49

3 Answers 3

13
$\begingroup$

There have been several studies in the past that have proposed plans to fly robotic aircraft on Mars (before ingenuity).

One interesting example was the "Aerial Regional-scale Environmental Survey" (ARES) mission, which proposed sending a robotic, rocket-powered aircraft to measure local crustal magnetism and near surface atmospheric chemistry.

The mission design proposed separating and deploying the aircraft from the aeroshell during entry and descent. The figure below (from this paper) gives an overview of the mission concept.

enter image description here

The mission was one of the finalists for the Mars Scout Programme competition (a previous NASA initiative to select low-cost robotic missions from proposals from the scientific community) and proposed launching in 2011. Ultimately NASA selected the Phoenix mission and later the MAVEN mission before the scout programme was retired.

However, there are several interesting papers published about the mission concept. NASA's Technical Reports Server is a great resource I can recommend you look into using to find some of these.

These papers sometimes include the contact information of the main authors. Perhaps you could try and write to them if you are keen to learn more. Though given the timeframe there is a potential risk some may have retired by now. Good luck!

$\endgroup$
4
$\begingroup$

You can fly a glider anywhere that you can fly an airplane. A glider is simply an airplane without an engine. If you turn the engine(s) off in a powered airplane, it effectively becomes a (relatively inefficient) glider and continues flying, albeit continuously bleeding off energy until it lands (unless it can fly into thermals or other such rising masses of air from which it can gain energy.)

It is possible to fly an airplane on Mars, but the atmosphere is so thin, that you need much larger wing area and/or much more airspeed in order to get the same amount of lift you would get on Earth. While you don't need to generate as much lift, the reduction in lift is much, much larger than the reduction in gravity.

According to the Wikipedia article on the atmosphere of Mars,

The highest atmospheric density on Mars is equal to the density found 35 km (22 mi) above the Earth's surface and is ≈0.020 kg/m^3.

For comparison, the density of Earth's atmosphere averages about 1.23 km/m^3 at mean sea level.

On Earth, it is theoretically possible to fly up to the Karman Line, which Karman calculated to be around 270,000 feet (51 miles or 82 km,) so 22 miles is well within that range, though it's getting to the point that aerodynamic flight is a lot harder than it is down at normal flight altitudes. The theoretical maximum flight altitude is based on the fact that, as you increase altitude, eventually the atmosphere becomes so thin that generating enough lift to maintain level flight requires 'flying' at orbital velocity - at which point you're in orbit, not aerodynamic flight. According to this paper (PDF), it seems that the line on Mars ends up being about the same, around 80 km above its surface. So, flying is indeed possible on Mars, but it will not be easy due to the very thin atmosphere.

However, as with any glider, you would need some way to launch the thing. They can't take off under their own power, as they don't have any. So, you would still need a tow airplane or some launch mechanism in order to get your glider into flight. Given the complication of doing that, you're likely better off just building a powered airplane instead. Or sticking with rotorcraft like Curiosity.

For an amusing description of what aerodynamic flight on Mars would be like, I would recommend the xkcd What-If "Interplanetary Cessna," which humorously explores how well (or, in most cases, how poorly) an electric-powered Cessna 172 would fly on the various bodies around our solar system. (xkcd is a web comic written by a physicist and its "What-If" section humorously answers various physics-related questions.)

$\endgroup$
7
  • $\begingroup$ Larger wing area or smaller scale? OP is asking for a crewed glider, so palm of the hand scale is off the table? $\endgroup$
    – mckenzm
    Commented Aug 8, 2023 at 1:05
  • $\begingroup$ @mckenzm As always, scale depends on the designed mission. My point regarding wing area and/or speed was that, for any given payload requirement, an airplane designed to fly on Mars will need to have larger wings and/or fly faster than one designed for the same mission on Earth. Whether it needs to carry 100 grams or 100 tons just comes down to what you want to do with it. $\endgroup$
    – reirab
    Commented Aug 8, 2023 at 3:50
  • $\begingroup$ Regarding launching, you're forgetting that anything reaching Mars is going to be dropping from the sky at hypersonic speeds, so you never need to touch the ground to fly. $\endgroup$
    – user71659
    Commented Aug 8, 2023 at 21:17
  • 1
    $\begingroup$ More "and" than "or". x-plane.com/adventures/mars.html — control authority is a big problem. With big wings and high speed you can stay aloft, but your turning radius is gigantic and landing is probably best avoided entirely. $\endgroup$
    – hobbs
    Commented Aug 8, 2023 at 21:37
  • $\begingroup$ @user71659 I wasn't really forgetting so much as assuming that it would need to be more like Curiosity and be protected by something that could survive entry and then deployed from the surface. It is technically possible to drop a glider in from space, but that presents a whole new range of engineering challenges that are likely worse than the existing ones. And, of course, that only works for the first launch. If you want the vehicle to be reusable, it still needs a separate launch mechanism. $\endgroup$
    – reirab
    Commented Aug 8, 2023 at 21:42
0
$\begingroup$

This is partly the subject of "The Long Mars" by Pratchett and Baxter. https://en.wikipedia.org/wiki/The_Long_Mars

Whilst it's Sci-Fi there are sensible and practical background details, such as testing at very high altitude on earth, as you suggest.

$\endgroup$
2
  • 1
    $\begingroup$ Hi and welcome to space SE! This does not appear to answer the question of 'is it possible', just that two authors thought it made sense for their story. If you want to reference the book you'd be better of looking up the included details and seeing if they do in fact make sense in terms of actual numbers. $\endgroup$ Commented Aug 8, 2023 at 11:04
  • 1
    $\begingroup$ Your answer could be improved with additional supporting information. Please edit to add further details, such as citations or documentation, so that others can confirm that your answer is correct. You can find more information on how to write good answers in the help center. $\endgroup$
    – Community Bot
    Commented Aug 8, 2023 at 11:05

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.