10 ms·

This is pretty sad but also pretty amazing. The original plan was for five flights of around 90 seconds each, and it looks like it finally failed on flight 72 w

by tedivm 3y ago

This is pretty sad but also pretty amazing. The original plan was for five flights of around 90 seconds each, and it looks like it finally failed on flight 72 with a total from all flights of two hours, eight minutes and eighteen seconds of flight time. All of this in an extremely thin atmosphere.

roughly 3y ago
NASA’s got a history of their rovers overperforming like this. Between this and Webb, it’s hard to argue they’re not the best out there.
- jasonpeacock 3y ago
  It's less about being the best (no criticism of NASA) but rather engineering decisions to _guarantee_ the planned mission, which means you over-engineer and thus get extra performance/reliability. You're not willing to accept the statistical risk that may end a mission early.
  - WalterBright 3y ago
    Since it doesn't need to be man-rated, spend less trying to make it perfect, and instead make more copies.
  - roughly 3y ago
    I agree that it's not strictly that NASA engineers are better engineers, but I do think there's part of this that's both cultural and becomes actual capability - I think even if you gave most engineering organizations the budget and mandate that NASA has, they still wouldn't be able to pull off something like Webb because they don't have the practice of it*. Capacity both builds and atrophies over time, and most places don't work to that standard often enough to maintain the capability to do so even if they wanted to. (*I don't necessarily mean the practice of shooting a rocket into space and launching a telescope, but the ability to build an object that can perform that exactly to its specifications under those kinds of circumstances.)
    - falserum 3y ago
      Mostly, with any endeavour, you never start in advanced state, you have basic solution, then refine and grow it. I guess formula would be: tech skills x organisational quality x budget x iterations already under the belt. Any of these factors can bring down the total result to zero. Not an easy task trying to control all of these. Nasa, congrats on successful mission, which now ended.
      - rrdharan 3y ago
        > with any [E]ndeavour I see what you did there.
    - nordsieck 3y ago
      > I think even if you gave most engineering organizations the budget and mandate that NASA has, they still wouldn't be able to pull off something like Webb because they don't have the practice of it IMO, Webb is a bad example. It was super over budget, late, and experienced a litany of problems. In contrast, most un-manned NASA projects are roughly on budget and generally have few issues. And even the ones that do, NASA often figures out how to correct them like the Hubble telescope.
      - adastra22 3y ago
        > In contrast, most un-manned NASA projects are roughly on budget and generally have few issues. This is simply not true. Maybe for some of the smallest Discovery or New Frontiers missions, but then those aren’t actually built by NASA/JPL. Mars Sample Return is also famously insanely late and over budget, and so have been most flagship missions.
    - firesteelrain 3y ago
      > NASA engineers are better engineers… JWST was built by primarily Northrop Grumman engineers
    - jorvi 3y ago
      Probably one of the purest examples of American exceptionalism. Give other space agencies the budget of NASA, let experience marinate and you will see similar performance. NASA does not have some sort of magical intrinsic property that makes engineers perform better by sheer effect of working under its umbrella.
  - superjan 3y ago
    I speculate that beyond that, extra longevity can also be used to increase your budget. If you plan for six months operations, you have a lower mission budget. They won’t shut you down after six months as long the device is still working.
  - EasyMark 3y ago
    The most over engineering in the world won't help you if you don't have good to great engineers when you're talking about stuff that is off world. So while they aren't going to be guaranteed be the top 10 engineers in the world, they are easily some of the best engineers in the world and deserve that to be acknowledged, NASA attracts the best, and even though they don't necessarily pay Silicon Valley salaries for cream of the crop, a lot of people aren't strictly motivated by money.
- alentred 3y ago
  I am in absolute awe of the results of research and engineering at NASA and many other space agencies for that matter. Nevertheless, I wonder: how much of the overperformance is in fact about playing it down in the first place? For example, what requirements for the Ingenuity helicopter were set for the engineers? Five flights or a 100 of flights?
  - jdewerd 3y ago
    Definitely a substantial portion of it, but we should be far more scandalized by the damage your typical runaway hype machine does to otherwise brilliant achievements than by NASA's successful efforts to wrangle expectations.
- edf13 3y ago
  Under promise, over deliver… that’s the smart engineering way.
  - The_Colonel 3y ago
    No, it's not. As the other commenter nicely explained, this is mostly a byproduct of a very, very low tolerance of failure and extremely difficult conditions, like the impossibility to test it beforehand in the real environment. Under promise, overdeliver, is a nice way to say that you're dishonest with the client. The fact you can overdeliver means you're making some trade-offs elsewhere, e.g. in design/production price, time, weight or somewhere else. Overdelivering is a nice byproduct, but it shouldn't be the goal.
    - lttlrck 3y ago
      When I see it used it's as a device to set expectations when there are so many variables at play that any promise or commitment would be foolish, lead to disappointment with no upside. And that's how I'd interpret it here too. It has nothing to do with dishonesty. Though I have no doubt that it might be used that way, that's fraudulent and a whole different ball-game commercially.
      - The_Colonel 3y ago
        > When I see it used it's as a device to set expectations when there are so many variables at play that any promise or commitment would be foolish, lead to disappointment with no upside. And that's how I'd interpret it here too. In such a situation, why not say like it is? Just explain the client the situation, what's the risk and for what additional cost it can be lowered. And I have no doubt this is what was happening in NASA, in other words this was no "underpromise and overdeliver", this was "explain the situation and agree on trade-offs leading to the best ratio of positive outcome for the price". I think the only situation where this approach is valid is when your client is not sophisticated enough to understand the trade-offs and make an optimal decision.
        3y ago
- giantrobot 3y ago
  It's not overperforming per se. NASA spacecraft/probes have primary, secondary, and auxiliary missions. Everything on the probe is designed and built with an eye to being able to complete secondary and auxiliary missions but the guarantee (insofar as anything can be) is the probe can accomplish its primary mission. Unfortunately this leads to uninformed reporters to make stupid claims like "a probe only designed to last 90 days...". There's no self destruct or planned obsolescence in NASA probes. They don't have an egg timer set to 90 days and then explode. The probes are designed to last at least as long as the ability for their consumables/power supply lasts. Consider the stresses of launch, transit through space, and insertion/landing are way worse than day to day conditions for a lot of probes. If they can survive all of that rolling around a desert is relatively easy (in comparison). If Ingenuity made one successful flight there was little reason it couldn't make more so long as it had the appropriate power available and the Martian Space Defense didn't shoot it down. Ingenuity didn't overperform, it performed according to its actual design and construction. It only overperformed misinformed media expectations.
  - wolverine876 3y ago
    > this leads to uninformed reporters to make stupid claims like "a probe only designed to last 90 days...". C'mon let's not blame the reporters. NASA pushes this line - why do think everyone repeats it, using the same language almost every time? You can even see it here on HN.
    - autoexec 3y ago
      If NASA says "We're going to send a helicopter to mars with the mission of taking 5 flights" is that somehow bad? If the quality of the engineering and the quality of the parts, and all the redundant systems and fail-safes required to absolutely guarantee that the helicopter will complete its mission of five flights then go on to allow the helicopter to take more flights before it finally breaks down, that isn't NASA lying to anyone or "pushing a line". If the media then tells the public that the helicopter was designed to make 5 flights, but got over 70 that's not misleading anyone.
      - 3y ago
- dotnet00 3y ago
  [flagged]
  - gumby 3y ago
    > It comes down to the fact that a poorly educated public and a ruling class of parasites has made it so NASA has negative room for failure. Both basically true yet overdone. Fundamentally the US has an extremely strong punitive blame culture. Too strong, in that it is a distraction, a spectacle, and inhibits resolution of an actual problem, if one even exists. I don't mean this just in government: it's a fundamental part of the American Weltanschauung, one oddly rarely discussed. It seems to be so fundamental that it's simply taken as a given, like the old "fish doesn't know it's wet" metaphor. FAA is a good example of an organization that implements an opposite approach: crash investigations follow a "what happened so we can address it, not punish" in air crashes, sometimes causing people to complain that "nobody was punished." But without the threat of punishment people are more willing to speak freely, so that hardware or procedures that need changing can actually change.
    - ordu 3y ago
      I don't know about USA politics to have an opinion on the matter, so I'd rather believe you assesment. But I want to add another point of data. Or rather point of view from outside. My experience of communication and collaboration with individual Americans points to the opposite direction. They are focused on a problem solving, not on a blame assignment. I can compare with my fellow Russians, I can't play games with them, because they kill all the fun looking for someone to blame. But at the same time, if we take a look at our Russian politicians... If they even look for someone to blame, they look for a blatant scapegoat. So, I mean, it seems like a complete reverse. Probably it is a coincidence or a result of a flawed methodology, but still...
      - smcin 3y ago
        The discussion here is specifically about US (political) oversight of government agencies like NASA, specifically after a failure. Not private companies, or tech, or problem-solving in general, or scenarios where positive incentives outweigh the likelihood of blame. Compare the huge public scrutiny of Space Shuttle failures vs the FAA being out-to-lunch on oversight of Boeing 737MAX for over a decade. Some people have commented that excessive scrutiny (e.g. at NASA) has resulted in changes in culture and the rise of risk-averse 'professional administrators'.
- sha2468 3y ago
  Who are their competitors?
- aurareturn 3y ago
  NASA’s got a history of their rovers overperforming like this. Between this and Webb, it’s hard to argue they’re not the best out there. That's like saying I could change this button's text color in 5 days of work, but I did it in 5 minutes instead. It's underpromising and overdelivering. It's a smart strategy because it's just hard to get stuff to work in space and on another planet. So it's best to underpromise. You can bet that the internal goal is a lot higher than the public goal.
- BurningFrog 3y ago
  Webb was 15 years late and 900% over budget. That's the wrong kind of overperforming.
rufus_foreman 3y ago
Underpromise, overdeliver.
- echelon 3y ago
  Five nines engineering.
wolverine876 3y ago
While I think NASA is the most incredible organization in human history, be wary of simple underpromising-and-overdelivering: If everything they build lasts longer than expected, not only are they giving bad estimates (which perverts allocation of resources), they are way too smart and experienced to be doing it unintentionally. Now if Ford Motor underpromised on your car, telling you it would last 2 years, you wouldn't buy it in the first place - you'd never find out that it really lasts 10 years. But I suspect NASA gets away with it because everyone is blown away by even the underpromised result - helicopters on Mars, holy sh-! - and also nobody has experience with how long Martian helicopters typically fly.
- tracerbulletx 3y ago
  Or the estimates are based around guaranteeing a high statistical chance they hit the estimate which is perfectly fine to do.
  - wolverine876 3y ago
    Yes, same thing - and I think we can assume that NASA has people smart enough to know it's the same thing.
  - Buttons840 3y ago
    Yeah, I've often wished organizations I've worked for would define what an "estimate" is. Do they want an estimate I think there's a 50% chance we'll hit, or do they want an estimate I think there's a 99% chance we'll hit? In my experience they want the 50% estimate and expect us to hit that estimate 99% of the time.
- bryanlarsen 3y ago
  A 99% chance of lasting 5 flights is likely the same build as a 50% chance of lasting 72. OTOH there is approximately 0% chance a Ford is going to last 10 years without any maintenance or repairs.
- gizmo686 3y ago
  They never said the helicopter would break down after 5 flights. They said it was designed for 5 flights. Shipping it to Mars is expensive and slow, so they build in a lot of margin to increase the odds that they meet the requirements. Take a much more common example: expiration dates. A product going bad before its expiration date is an issue. Potential a massive one that could kill people. A product that remains in good condition after its expiration date is fine. As a result, expiration dates almost always occur far before the product actually expires.
londons_explore 3y ago
Is flying in a thin atmosphere harder? Sure, there is less lift... But there is also less drag. So your rotors can go far faster with the same power input - and, roughly, it looks like the power needed to hover (for a craft of a given mass and size) is actually less on mars due to the lower gravity, despite the rotors moving super fast.
- sobellian 3y ago
  In the limit of no atmosphere, it's surely impossible. In the case of a thick, incompressible atmosphere (a body of water), even humans can do it.
  - Intralexical 3y ago
    "Titan's gravity is 14% of Earth's, and its atmosphere 50% denser. So if you can generate 9% of your Earth body weight in lift, you can fly on Titan." https://xkcd.com/620/ https://xkcd.com/620/
  - londons_explore 3y ago
    > even humans can do it. I think this is a misconception. Even in water, you cannot provide lift equal to your bodyweight. It is easier to swim (vs sink) in water because the water gives a large amount of buoyancy. However, in air and on mars, buoyancy is small enough to be negligible.
    - sobellian 3y ago
      It's true that buoyancy helps, but even so swimming clearly provides a greater propulsive force than doing the same motion in air despite the greater drag in water.
- malfist 3y ago
  Less drag means less lift. Drag is how rotars generate lift
- godelski 3y ago
EasyMark 3y ago
thanks for putting it in context :)
wait_a_minute 3y ago
That is an extremely impressive achievement. It boggles my mind. Amazing job NASA, Godspeed. Badass engineers all around. Great ROI, we should keep going on bigger projects. All that data...phew. Working there must feel like pure Americana each time you tap a key. I'd be coding extra just to enjoy that, especially seeing the level of impact these teams have. I wonder if they drink coffee while they build or if they found that it reduces performance for the engineers or for the astronauts?

by tedivm 3y ago

roughly 3y ago

NASA’s got a history of their rovers overperforming like this. Between this and Webb, it’s hard to argue they’re not the best out there.

jasonpeacock 3y ago
It's less about being the best (no criticism of NASA) but rather engineering decisions to _guarantee_ the planned mission, which means you over-engineer and thus get extra performance/reliability. You're not willing to accept the statistical risk that may end a mission early.
- WalterBright 3y ago
  Since it doesn't need to be man-rated, spend less trying to make it perfect, and instead make more copies.
- roughly 3y ago
  I agree that it's not strictly that NASA engineers are better engineers, but I do think there's part of this that's both cultural and becomes actual capability - I think even if you gave most engineering organizations the budget and mandate that NASA has, they still wouldn't be able to pull off something like Webb because they don't have the practice of it*. Capacity both builds and atrophies over time, and most places don't work to that standard often enough to maintain the capability to do so even if they wanted to. (*I don't necessarily mean the practice of shooting a rocket into space and launching a telescope, but the ability to build an object that can perform that exactly to its specifications under those kinds of circumstances.)
  - falserum 3y ago
    Mostly, with any endeavour, you never start in advanced state, you have basic solution, then refine and grow it. I guess formula would be: tech skills x organisational quality x budget x iterations already under the belt. Any of these factors can bring down the total result to zero. Not an easy task trying to control all of these. Nasa, congrats on successful mission, which now ended.
    - rrdharan 3y ago
      > with any [E]ndeavour I see what you did there.
  - nordsieck 3y ago
    > I think even if you gave most engineering organizations the budget and mandate that NASA has, they still wouldn't be able to pull off something like Webb because they don't have the practice of it IMO, Webb is a bad example. It was super over budget, late, and experienced a litany of problems. In contrast, most un-manned NASA projects are roughly on budget and generally have few issues. And even the ones that do, NASA often figures out how to correct them like the Hubble telescope.
    - adastra22 3y ago
      > In contrast, most un-manned NASA projects are roughly on budget and generally have few issues. This is simply not true. Maybe for some of the smallest Discovery or New Frontiers missions, but then those aren’t actually built by NASA/JPL. Mars Sample Return is also famously insanely late and over budget, and so have been most flagship missions.
  - firesteelrain 3y ago
    > NASA engineers are better engineers… JWST was built by primarily Northrop Grumman engineers
  - jorvi 3y ago
    Probably one of the purest examples of American exceptionalism. Give other space agencies the budget of NASA, let experience marinate and you will see similar performance. NASA does not have some sort of magical intrinsic property that makes engineers perform better by sheer effect of working under its umbrella.
- superjan 3y ago
  I speculate that beyond that, extra longevity can also be used to increase your budget. If you plan for six months operations, you have a lower mission budget. They won’t shut you down after six months as long the device is still working.
- EasyMark 3y ago
  The most over engineering in the world won't help you if you don't have good to great engineers when you're talking about stuff that is off world. So while they aren't going to be guaranteed be the top 10 engineers in the world, they are easily some of the best engineers in the world and deserve that to be acknowledged, NASA attracts the best, and even though they don't necessarily pay Silicon Valley salaries for cream of the crop, a lot of people aren't strictly motivated by money.
alentred 3y ago
I am in absolute awe of the results of research and engineering at NASA and many other space agencies for that matter. Nevertheless, I wonder: how much of the overperformance is in fact about playing it down in the first place? For example, what requirements for the Ingenuity helicopter were set for the engineers? Five flights or a 100 of flights?
- jdewerd 3y ago
  Definitely a substantial portion of it, but we should be far more scandalized by the damage your typical runaway hype machine does to otherwise brilliant achievements than by NASA's successful efforts to wrangle expectations.
edf13 3y ago
Under promise, over deliver… that’s the smart engineering way.
- The_Colonel 3y ago
  No, it's not. As the other commenter nicely explained, this is mostly a byproduct of a very, very low tolerance of failure and extremely difficult conditions, like the impossibility to test it beforehand in the real environment. Under promise, overdeliver, is a nice way to say that you're dishonest with the client. The fact you can overdeliver means you're making some trade-offs elsewhere, e.g. in design/production price, time, weight or somewhere else. Overdelivering is a nice byproduct, but it shouldn't be the goal.
  - lttlrck 3y ago
    When I see it used it's as a device to set expectations when there are so many variables at play that any promise or commitment would be foolish, lead to disappointment with no upside. And that's how I'd interpret it here too. It has nothing to do with dishonesty. Though I have no doubt that it might be used that way, that's fraudulent and a whole different ball-game commercially.
    - The_Colonel 3y ago
      > When I see it used it's as a device to set expectations when there are so many variables at play that any promise or commitment would be foolish, lead to disappointment with no upside. And that's how I'd interpret it here too. In such a situation, why not say like it is? Just explain the client the situation, what's the risk and for what additional cost it can be lowered. And I have no doubt this is what was happening in NASA, in other words this was no "underpromise and overdeliver", this was "explain the situation and agree on trade-offs leading to the best ratio of positive outcome for the price". I think the only situation where this approach is valid is when your client is not sophisticated enough to understand the trade-offs and make an optimal decision.
      - 3y ago
giantrobot 3y ago
It's not overperforming per se. NASA spacecraft/probes have primary, secondary, and auxiliary missions. Everything on the probe is designed and built with an eye to being able to complete secondary and auxiliary missions but the guarantee (insofar as anything can be) is the probe can accomplish its primary mission. Unfortunately this leads to uninformed reporters to make stupid claims like "a probe only designed to last 90 days...". There's no self destruct or planned obsolescence in NASA probes. They don't have an egg timer set to 90 days and then explode. The probes are designed to last at least as long as the ability for their consumables/power supply lasts. Consider the stresses of launch, transit through space, and insertion/landing are way worse than day to day conditions for a lot of probes. If they can survive all of that rolling around a desert is relatively easy (in comparison). If Ingenuity made one successful flight there was little reason it couldn't make more so long as it had the appropriate power available and the Martian Space Defense didn't shoot it down. Ingenuity didn't overperform, it performed according to its actual design and construction. It only overperformed misinformed media expectations.
- wolverine876 3y ago
  > this leads to uninformed reporters to make stupid claims like "a probe only designed to last 90 days...". C'mon let's not blame the reporters. NASA pushes this line - why do think everyone repeats it, using the same language almost every time? You can even see it here on HN.
  - autoexec 3y ago
    If NASA says "We're going to send a helicopter to mars with the mission of taking 5 flights" is that somehow bad? If the quality of the engineering and the quality of the parts, and all the redundant systems and fail-safes required to absolutely guarantee that the helicopter will complete its mission of five flights then go on to allow the helicopter to take more flights before it finally breaks down, that isn't NASA lying to anyone or "pushing a line". If the media then tells the public that the helicopter was designed to make 5 flights, but got over 70 that's not misleading anyone.
    - 3y ago
dotnet00 3y ago
[flagged]
- gumby 3y ago
  > It comes down to the fact that a poorly educated public and a ruling class of parasites has made it so NASA has negative room for failure. Both basically true yet overdone. Fundamentally the US has an extremely strong punitive blame culture. Too strong, in that it is a distraction, a spectacle, and inhibits resolution of an actual problem, if one even exists. I don't mean this just in government: it's a fundamental part of the American Weltanschauung, one oddly rarely discussed. It seems to be so fundamental that it's simply taken as a given, like the old "fish doesn't know it's wet" metaphor. FAA is a good example of an organization that implements an opposite approach: crash investigations follow a "what happened so we can address it, not punish" in air crashes, sometimes causing people to complain that "nobody was punished." But without the threat of punishment people are more willing to speak freely, so that hardware or procedures that need changing can actually change.
  - ordu 3y ago
    I don't know about USA politics to have an opinion on the matter, so I'd rather believe you assesment. But I want to add another point of data. Or rather point of view from outside. My experience of communication and collaboration with individual Americans points to the opposite direction. They are focused on a problem solving, not on a blame assignment. I can compare with my fellow Russians, I can't play games with them, because they kill all the fun looking for someone to blame. But at the same time, if we take a look at our Russian politicians... If they even look for someone to blame, they look for a blatant scapegoat. So, I mean, it seems like a complete reverse. Probably it is a coincidence or a result of a flawed methodology, but still...
    - smcin 3y ago
      The discussion here is specifically about US (political) oversight of government agencies like NASA, specifically after a failure. Not private companies, or tech, or problem-solving in general, or scenarios where positive incentives outweigh the likelihood of blame. Compare the huge public scrutiny of Space Shuttle failures vs the FAA being out-to-lunch on oversight of Boeing 737MAX for over a decade. Some people have commented that excessive scrutiny (e.g. at NASA) has resulted in changes in culture and the rise of risk-averse 'professional administrators'.
sha2468 3y ago
Who are their competitors?
aurareturn 3y ago
NASA’s got a history of their rovers overperforming like this. Between this and Webb, it’s hard to argue they’re not the best out there. That's like saying I could change this button's text color in 5 days of work, but I did it in 5 minutes instead. It's underpromising and overdelivering. It's a smart strategy because it's just hard to get stuff to work in space and on another planet. So it's best to underpromise. You can bet that the internal goal is a lot higher than the public goal.
BurningFrog 3y ago
Webb was 15 years late and 900% over budget. That's the wrong kind of overperforming.

rufus_foreman 3y ago

Underpromise, overdeliver.

echelon 3y ago
Five nines engineering.

wolverine876 3y ago

While I think NASA is the most incredible organization in human history, be wary of simple underpromising-and-overdelivering: If everything they build lasts longer than expected, not only are they giving bad estimates (which perverts allocation of resources), they are way too smart and experienced to be doing it unintentionally. Now if Ford Motor underpromised on your car, telling you it would last 2 years, you wouldn't buy it in the first place - you'd never find out that it really lasts 10 years. But I suspect NASA gets away with it because everyone is blown away by even the underpromised result - helicopters on Mars, holy sh-! - and also nobody has experience with how long Martian helicopters typically fly.

tracerbulletx 3y ago
Or the estimates are based around guaranteeing a high statistical chance they hit the estimate which is perfectly fine to do.
- wolverine876 3y ago
  Yes, same thing - and I think we can assume that NASA has people smart enough to know it's the same thing.
- Buttons840 3y ago
  Yeah, I've often wished organizations I've worked for would define what an "estimate" is. Do they want an estimate I think there's a 50% chance we'll hit, or do they want an estimate I think there's a 99% chance we'll hit? In my experience they want the 50% estimate and expect us to hit that estimate 99% of the time.
bryanlarsen 3y ago
A 99% chance of lasting 5 flights is likely the same build as a 50% chance of lasting 72. OTOH there is approximately 0% chance a Ford is going to last 10 years without any maintenance or repairs.
gizmo686 3y ago
They never said the helicopter would break down after 5 flights. They said it was designed for 5 flights. Shipping it to Mars is expensive and slow, so they build in a lot of margin to increase the odds that they meet the requirements. Take a much more common example: expiration dates. A product going bad before its expiration date is an issue. Potential a massive one that could kill people. A product that remains in good condition after its expiration date is fine. As a result, expiration dates almost always occur far before the product actually expires.

londons_explore 3y ago

Is flying in a thin atmosphere harder? Sure, there is less lift... But there is also less drag. So your rotors can go far faster with the same power input - and, roughly, it looks like the power needed to hover (for a craft of a given mass and size) is actually less on mars due to the lower gravity, despite the rotors moving super fast.

sobellian 3y ago
In the limit of no atmosphere, it's surely impossible. In the case of a thick, incompressible atmosphere (a body of water), even humans can do it.
- Intralexical 3y ago
  "Titan's gravity is 14% of Earth's, and its atmosphere 50% denser. So if you can generate 9% of your Earth body weight in lift, you can fly on Titan." https://xkcd.com/620/ https://xkcd.com/620/
- londons_explore 3y ago
  > even humans can do it. I think this is a misconception. Even in water, you cannot provide lift equal to your bodyweight. It is easier to swim (vs sink) in water because the water gives a large amount of buoyancy. However, in air and on mars, buoyancy is small enough to be negligible.
  - sobellian 3y ago
    It's true that buoyancy helps, but even so swimming clearly provides a greater propulsive force than doing the same motion in air despite the greater drag in water.
malfist 3y ago
Less drag means less lift. Drag is how rotars generate lift
godelski 3y ago

EasyMark 3y ago

thanks for putting it in context :)

wait_a_minute 3y ago

That is an extremely impressive achievement. It boggles my mind. Amazing job NASA, Godspeed. Badass engineers all around. Great ROI, we should keep going on bigger projects. All that data...phew. Working there must feel like pure Americana each time you tap a key. I'd be coding extra just to enjoy that, especially seeing the level of impact these teams have. I wonder if they drink coffee while they build or if they found that it reduces performance for the engineers or for the astronauts?