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Goose flying upside down is simply showing off, say experts
- sorokod 5y agoCue the conversation on how wing works.
- SonicScrub 5y agoOne of my favourite pointless internet arguments! I usually just point to this link and walk away: https://www.scientificamerican.com/article/no-one-can-explain-why-planes-stay-in-the-air/ https://www.scientificamerican.com/article/no-one-can-explai... Answer: because a surface of a certain geometry produces a force perpendicular to fluid flow as per the Navier-Stokes equations. But that's not a good explanation to give a room full 2nd graders, therefore your pet-explanation will have to make a compromise somewhere. You are all equally right and wrong at the same time. Unless you say "equal transit theory". Then you are just wrong.
- nas 5y agoThat sounds like the problem of explaining how magnetism works. Engineers and scientists understand very well how airfoils generate lift. It is not some kind of mystery like the article implies. It is true that most of the popular simplified explanations are incorrect. Flat plate airfoils generate lift if they have positive angles of attack. Airplanes can fly upside down. At fractional mach numbers, pressure above and below the wings is essentially equal. If you are not flying near the speed of light, Newton's laws apply. So, if you want simple explanation, the wing deflects air downwards and that pushes the airplane up. If you put your hand outside the car window at an angle, you will feel a force. Should be simple enough for 2nd graders.
- deleted 5y ago[deleted]
- SonicScrub 5y agoThe article doesn't imply it's a mystery, only that simple one-liner explanations are insufficient. The headline is reasonably clickbait-y. The momentum theory of lift is simple, intuitive, but unfortunately incomplete (just as the differential pressure explanation). It's covered in the article. > But taken by itself, the principle of action and reaction also fails to explain the lower pressure atop the wing, which exists in that region irrespective of whether the airfoil is cambered. It is only when an airplane lands and comes to a halt that the region of lower pressure atop the wing disappears, returns to ambient pressure, and becomes the same at both top and bottom. But as long as a plane is flying, that region of lower pressure is an inescapable element of aerodynamic lift, and it must be explained. Also I want to address this: > At fractional mach numbers, pressure above and below the wings is essentially equal. Surely you mean density? Air pressure is certainly not the same above and below, as differential pressure integrated over the surface is equal to the lift force generated by the wing. So no, while the Newton's explanation is a great explanation for a second grade classroom, it is not complete.
- twic 5y ago> But taken by itself, the principle of action and reaction also fails to explain the lower pressure atop the wing What? The pressure is lower on top of the wing and higher below because the air is being pushed downwards by the wing. I will happily explain this to any second-grade classrooms you find yourself having trouble with.
- SonicScrub 5y agoAnd how is that air moving from the upper surface to the lower surface of the wing? is it magically permeating the wing surface? Keep in mind that the vast majority of the pressure differential comes from upper surface suction rather than a pressure increase on the lower surface. At shallow angles of attack there is often little or no increase in pressure on the lower surface; nevertheless lift is produced. Your simplification does not adequately explain this, as addressed in the section of the article subtitled: "Turning on the Reciprocity of Lift" > Nevertheless, there are at this point only a few outstanding matters that require explanation. Lift, as you will recall, is the result of the pressure differences between the top and bottom parts of an airfoil. We already have an acceptable explanation for what happens at the bottom part of an airfoil: the oncoming air pushes on the wing both vertically (producing lift) and horizontally (producing drag). The upward push exists in the form of higher pressure below the wing, and this higher pressure is a result of simple Newtonian action and reaction. > Things are quite different at the top of the wing, however. A region of lower pressure exists there that is also part of the aerodynamic lifting force. But if neither Bernoulli’s principle nor Newton’s third law explains it, what does? We know from streamlines that the air above the wing adheres closely to the downward curvature of the airfoil. But why must the parcels of air moving across the wing’s top surface follow its downward curvature? Why can’t they separate from it and fly straight back?
- WJW 5y agoThe article does specify that "nobody can explain how wings work", not that "nobody knows how wings work". It also tries to go into "but WHY do the Navier-Stokes equations work like this", which is just not how physics works. But yeah, there is just not an explanation that is both simple and complete and journalists have a pretty rough time dealing with that.
- nautilius 5y agoThe pressures above and below the wing are absolutely not equal, even at idealized incompressible flow (zero Mach number). Pressure distribution: https://www.researchgate.net/publication/262976779_Aerodynamic_Optimal_Shape_Design_Based_on_Body-Fitted_Grid_Generation/figures https://www.researchgate.net/publication/262976779_Aerodynam... Pressure contour plot: https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.ripublication.com%2Fijaerspl2019%2Fijaerv14n14spl_19.pdf&psig=AOvVaw2UO2mQLCPRgoYr3uTvxnig&ust=1628125751995000&source=images&cd=vfe&ved=0CAcQjRxqFwoTCOi5s5qXlvICFQAAAAAdAAAAABAF https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.ripubl...
- amelius 5y ago> That sounds like the problem of explaining how magnetism works. https://www.youtube.com/watch?v=36GT2zI8lVA https://www.youtube.com/watch?v=36GT2zI8lVA
- svachalek 5y agoIt seems similar to explaining monads. If you stick to the math and logic, it's quite clear and hard to confuse. But if you succumb to the common temptation to explain it in a more "intuitive" way, it seems you are doomed to tumble down the stairs in the dark.
- ummonk 5y agoThat article seems to oddly assume that in the Newtonian explanation, deflection of air is implied to only happen below the airfoil rather than above. At least when I explain lift that way, I gesture air being sent downwards both along the top and bottom of the airfoil. As to explaining why air above the airfoil has to go downwards it seems pretty obvious that the air gets sucked into the gap left by the airfoil, but more importantly the article left out the Kutta condition that air doesn't wrap around a sharp trailing edge. This is both an intuitive phenomenon and crucial to the estimation of lift.
- tzs 5y agoOne of the reasons there is so much confusion on this is that there are at least two different valid ways to look at it, but any given person usually only knows one of them (or rather, a simplified version of a serious misunderstanding of one of them). Different people know a different one of them, and thus argument breaks out whenever the topic comes up. NASA has a bunch of aerodynamics educational material on their old Glenn Research Center website. Here's a page on these two different ways to look at lift [1]. Very briefly, the gas flow has to simultaneously conserve mass, momentum, and energy. One approach is to consider conservation of energy. When you work out the implications of that you get different flow velocity over different parts of the wing and different pressure due to those differences. When you integrate the pressure over the whole wing you find that you get lift. The other approach is to consider conservation of momentum. Working out the implications of that, you get velocity differences in the flow. If you integrate those around the whole wing, you find that there is a net turning of the flow downward. Conservation of momentum requires that the wing gets momentum opposite of that and we have lift. [1] https://www.grc.nasa.gov/www/k-12/airplane/bernnew.html https://www.grc.nasa.gov/www/k-12/airplane/bernnew.html
- perl4ever 5y agoDoes this all work for symmetric wing cross sections?
- dylan604 5y ago>or rather, a simplified version of a serious misunderstanding of one of them or both?
- jerf 5y agoI think it's a classic case of not understanding equality, hiding behind enough complexity that it's a bit more complicated than usual. Many people have a hard time not reading equalities as an implication... if there's a mass and an acceleration, then there's a force. But the equality says, it's the same. It isn't an if-then, it is that whereever there is a mass that is accelerating, that is force. The force doesn't "cause" the mass to accelerate and the mass accelerating doesn't "cause" the force; they're equal, they're the same thing, trying to wedge in between the two of them is a fatal error, and a very common one in physics education. Both of those approaches are equal. Or, to put it another way, it isn't that the fast moving air and the slow moving air "causing" a pressure differential which then "causes" lift... it's one integrated process. They aren't separable. You can't have different levels of pressure without some effect on air velocity, you can't have forces in the air without some effect on pressure, etc. The whole argument is all "But what causes what?" and the only correct answer is that it's an equality, not an implication. It can only be properly understood as a single whole that can be looked at in several ways.
- filoeleven 5y agoI usually just say “Bernoulli’s principle” with a hand-wave. It’s an ignorant dismissal accompanied by a practical demonstration. Works great at parties inside wind tunnels.
- ambirex 5y agosay experts who are flightless and honestly a little jealous ;)
- ProAm 5y agoThis usually results in a flat spin and death heading out to sea.
- CommonGuy 5y agoWhat is this kind of annoying cookie consent dialog? Takes over a minute to disable advertisment cookies, probably just to coerce users into accepting all cookies
- callesgg 5y agoTook 20s to just accept them.
- timdaub 5y agoI closed the page when it popped up. I didn't end up reading anything on the site.
- mngnt 5y ago> This may take up to a few minutes to process. It did for me. When it got to "applying settings", I scrolled down and started reading. Then, as I was half way through, it scrolled all the way up just to proudly announce that the Sisyphean task of NOT tracking me is done. > You have successfully updated your Cookie settings.
- brink 5y agoCan we just appreciate the funny article?
- Shank 5y agoThis is why I really suggest using uBlock Origin, blocking all of the trackers, and then removing the cookie popups. That would have been blocked by the "EasyList Cookie" and "Fanboy's Annoyances" list(s), with the other default filters in place for trackers.
- throwanem 5y agoOkay, but the real question here: What'd he shoot it with? (Old photographer joke: You're shooting by a lake on a cloudy day and you happen on someone drowning, and have to choose between dropping your gear to run to the rescue and getting a shot to sell the local paper. So - what f-stop do you use?)
- dylan604 5y agof/8. I'd be more concerned about shutter speed. If the drownee is flailing their arms, dragging the shutter slower might yield a more dramatic look with the motion blur. Too high of shutter speed so the action is frozen might look more like someone rehearsing their part in a synchronized routine. Keeping the subject in focus is more important as a decent telephoto will get you an out of focus background. Unless you're just a dick and use a wide angle but wade out into the water to get a decent framing.
- lmilcin 5y agoWith f/8 on a cloudy day you might get problem getting sharp image of the arms or have to settle on grainy image, regardless of the lens. I would use fastest aperture I can that is still sharp and just shot a bunch of frames very quickly in hopes I can get arms in just the right, dramatic position. As to whether to shoot wide or tele, if you feel you have enough time try to get subject to fill the frame first, while he still looks lively, and then quickly change the lens to get some additional shots with the background.
- dylan604 5y agodragging the shutter slow enough to get motion blur would also make up for any difference in light loss. would require some sort of stabilization though. if you don't have a tri/monopod, you can set it on the ground and use some rocks or sticks (you're near a lake) to prop up the lens. also, i'd suggest using a 1 second shutter release delay to not have any bounce from you pressing the buttons on such a slow shutter. also, digital cameras could just compensate slower f-stop with higher ISO if necessary
- cupcake-unicorn 5y agoHaha, real /r/nottheonion vibes here :) Would love to see a video
- jkaplowitz 5y agoI first saw this news on that exact sub. :)
- isoprophlex 5y agoVery interesting... website is pretty terrible though. Here's a link to a translated local source with the same info: https://www-rtlnieuws-nl.translate.goog/editienl/artikel/5244505/bijzonder-plaatje-gans-vliegt-op-kop-voorbij-vincent-cornelissen?_x_tr_sl=nl&_x_tr_tl=en&_x_tr_hl=nl&_x_tr_pto=ajax,nv,elem https://www-rtlnieuws-nl.translate.goog/editienl/artikel/524...
- iforgetmypass 5y agoThe original source is some strange indie news wire service I've never heard of before, "Zenger news."
- datavirtue 5y ago"Once young geese have mastered flying, they start to see what is possible and how far they can go, pulling in random JavaScript libraries and changing the testing framework for no reason."
- salawat 5y ago>pulling in random JavaScript libraries and changing the testing framework for no reason." Offenders will be hoisted up by the toes with yarn and beaten into unconsciousness with an organic carrot. Signed: Quality Assurance
- projectramo 5y agoSigh. That was Maverick in the (we prefer the term) inverted dive. Goose was just along for the ride.
- anonu 5y agoTrying to find more photos of this phenomenon [1][2] [1] https://www.nikoncafe.com/threads/wow-canada-goose-flying-upside-down.324877/ https://www.nikoncafe.com/threads/wow-canada-goose-flying-up... [2] https://www.telegraph.co.uk/news/earth/wildlife/5353933/Goose-photographed-flying-upside-down.html https://www.telegraph.co.uk/news/earth/wildlife/5353933/Goos...
- deleted 5y ago[deleted]
- tintt 5y agoGeese are cool dudes
- foolinaround 5y agoMy memory is weird! As I was reading this link, i suddenly thought of the movie 'Top Gun' - which I have'nt watched or discussed this decade!! And then a few minutes later, it dawned on me! There is this character called 'Goose'!
- dylan604 5y agoIf only you'd read the comments thread before posting this...
- noduerme 5y ago>> This aerial acrobatic resembles a falling leaf and may be used to avoid avian predators or a long, slow descent over an area where hunters for sport or food are present. Reminds me of a description I heard from a DEA pilot of the combat landings they would pull in Colombia. https://www.businessinsider.com/a-c-130-pilots-view-of-a-combat-landing-2015-7 https://www.businessinsider.com/a-c-130-pilots-view-of-a-com...
- hahamrfunnyguy 5y agoA Goose flying upside down: https://www.youtube.com/watch?v=7AeJ3aLm0UY https://www.youtube.com/watch?v=7AeJ3aLm0UY
- mc32 5y agoAnd more geese flying upside down one-upping or me tooing each other: https://www.youtube.com/watch?v=amhgFdyW1Q8 https://www.youtube.com/watch?v=amhgFdyW1Q8
- blunte 5y agoI saw this exact thing a couple of months ago not so far from Arhnem. (I thought it might be a crane, but it was moving very fast... so I could be mistaken.) This bird was diving at about 30-45 degrees from fairly high, and it suddenly inverted, stayed inverted for a second or so, and then righted itself. It was moving very fast, and you could actually hear the sound (and the changes of sound) of the air as it was moving through it. There were no other airborne birds of that size that I could see anywhere near it, so I initially thought it was dying or otherwise out of control. But then it descended below view, and I never heard a thump. I searched for inverted bird flight immediately after and learned that there are a number of observed cases where birds may do that. One theory is that they sometimes do it because they enjoy it. Other theories of course involve chasing prey, observing things, showing off, etc. But I like the idea that a bird might just be having fun. I mean, if I could fly, I think I would screw around all the time just because I could. After all, children will just run around wildly just because they can run.
- brundolf 5y agoWe often assume non-human animals are totally focused on the logical business of survival. But we aren't, and I don't see why they would be any different
- jon_richards 5y agoHere's a fun example https://www.youtube.com/watch?v=EGaSHDmuAPg https://www.youtube.com/watch?v=EGaSHDmuAPg
- emi2k01 5y agoThere's an interesting comment in that video that says the bird thinks it's an egg and it's trying to break it open. I don't know if that's true but I wanted to point it out to hopefully get some answers here.
- kadoban 5y agoInitially sounds possible. Only question I'd have is...how adept is that kind of bird at slurping up splattered egg innards? That's a _lot_ of force it's using if it thinks it's an egg. If it's trying to eat it, wouldn't it either squish it in its beak or stab it a bit to just break the top?
- rsync 5y ago"Because I was inverted." https://www.youtube.com/watch?v=ump0N5yOpkM https://www.youtube.com/watch?v=ump0N5yOpkM
- sparker72678 5y agoI assumed this was the goose they were talking about. A+
- Areading314 5y agoI thought this was going to be about Top Gun
- soheil 5y agoWell that Goose broke his neck
- chrismorgan 5y agoOne moderately windy day when cycling, I encountered a bird that I concluded was practising precision soaring and simply enjoying itself. It was constantly adjusting its posture as necessary so that it could hover roughly in-place, with just the occasional flap needed. Then after maybe a minute it’d abruptly change position by a few metres in any direction, and start hovering again. I watched it for more than five minutes before it flew away. I also remember another time watching a sparrow land on a wire fence backwards in a fairly strong wind: it flew with the wind towards the fence, then turned around in mid-air a metre or two before it reached the fence, was blown the rest of the way and landed neatly.
- Swenrekcah 5y agoYour story reminds me of this video of a snowboarding crow: https://m.youtube.com/watch?v=3dWw9GLcOeA https://m.youtube.com/watch?v=3dWw9GLcOeA
- yellowapple 5y agoThanks; that sent me on yet another YouTube rabbit hole around crows and their zany behavior.
- quercusa 5y agoMature red-tailed hawks can hover or soar with only the slightest movements but the juveniles are comically bad at it.
- MikeDelta 5y agoI sometimes forget that also animals need to practice in order to become good at something.
- ajuc 5y agoI've seen crows do that near a corner house with L-shaped roof. The wind was going from the backyard, hitting the sloped roof and blowing straight up in that corner and a lot of crows were jumping from the roof, hovering on the wind for a few minutes and returning to the roof when they couldn't keep in the stream.
- Iwan-Zotow 5y agocooling the balls, so to speak
- amarant 5y agoThat page has probably the worst cookie banner experience I've ever seen! 3 pop-ups later, 5 second delay between each, and the page jumping back to the top after each of them, I gave up and decided no article is worth this amount of suffering. I got to read the first paragraph tho, I guess that's something....