Let Me Throw You a Curve: How a Wing Produces Lift
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- Опубліковано 15 жов 2019
- How does a wing generate lift? It's all about bending the air. That's right. Bend the air and something amazing happens. That amazing thing is called "lift." Much like the judo master who's an expert at bending people, the wing is an excellent tool for bending air. Here's a simple yet accurate representation of how a wing develops lift. This presentation covers both the tangential and normal acceleration of the airstream without once mentioning those two terms. If you'd like to learn more about my books and eLearning courses, please visit: www.rodmachado.com
HERE'S SOMETHING TO THINK ABOUT:
There are 1,000+ videos on UA-cam that describe how lift occurs. That suggests that there is no one "right way" to describe how lift occurs. After all, many of these videos offering different explanations for lift are made by people with impressive academic credentials who've spent their entire lives studying the subject. Yet, their explanations for lift are sometimes wildly different. This "difference" in explanations is the important message here. That message is, "There is no one correct way to explain how lift occurs because lift is a very complex phenomenon." The best any instructor can do is to offer an explanation that comports with scientific principles and allows students to use this explanation to better understand how to fly an airplane.
Great explanation, I really enjoyed that you covered how circulation, newtons laws, conservation of momentum, and pressure differentials cause lift. The only thing I would add in your video is a clearer picture of how the pressure gradient actually curves well before the streamlines reach the airfoil. In addition to this, you mentioned that an increase in velocity causes some increase in pressure. When in fact velocity and pressure do not have a cause-effect relationship but are coupled. Thanks!
Sir, before this I had hunted around the internet for hours puzzled with varies explanations. Thank you so much for helping me understand how a circulatory flow induces a pressure difference. This clears up Wiki's explanation tremendously. Thanks so much!
More instructors could and should explain "aerodynamic lift" this way.
Of course there are many ways to attack the subject, but your explanation and visuals were clear, simple, and on point!
You are my hero 😍 and one of the most greats instructors out their, I really think u have thought me to fly, aditude power trim !? I was 21 when I brought FSX and did the pilot tutorial, I still have ur voice in my head! ever since! from the simulator! and if fact I have keep the laptop in which I have passed my PPL 😂 course, I am 37 now and hope to see someday sir
Appreciate all your contributions
God bless u 😇🙏
Thank you, Shahriyar. That's very sweet of you to say. I sure do appreciate it.
Best,
Rod Machado
Hey Rod, thanks for the fascinating explanation of lift! I’ve always been interested in this question. I feel like I have a pretty good grasp of it now.
Greetings Greg:
Thank you for that comment. I sure do appreciate it. Just for fun, allow me to pontificate on why there are so many varied explanations for lift. This is not related to your comment. It's simply something I wanted to write about in these comments for a while.
Here's something to think about. There are 1,000+ videos on UA-cam that describe how lift occurs. That suggests that there is no one "right way" to describe how lift occurs. After all, many of these videos offering different explanations for lift are made by people with impressive academic credentials who've spent their entire lives studying the subject. Yet, their explanations for lift are sometimes wildly different. This "difference" in explanations is the important message here. That message is, "There is no one correct way to explain how lift occurs because lift is a very complex phenomenon." The best any instructor can do is to offer an explanation that comports with scientific principles and allows students to use this explanation to better understand how airplanes fly.
Best,
Rod Machado
I love learning more and more about aeronautics! That said, right now, I'm mostly interested in knowing what I need to know to fly a plane well, not how to design a plane or an airfoil. I know enough that part of me is frustrated at the various "oversimplifications," but... again, you just need to know the right things to fly a plane well. And, as one can expect from you, you did a great job covering what is actually important. We bend the flow of air down, and as a result, stay up! That's a fantastic starting point, and building from there! (and keeping the memory of Huey P Newton alive... maybe you DO want to foment challenges to society's unspoken paradigms and overthrow the status quo, and the Man, man!)
Greetings Thomas:
Thank you for your comment. Want to learn how to fly? Pay a visit to the library and borrow a copy of, "Rod Machado's How to Fly an Airplane." That will get you started.
Best,
Rod
Fun fact: when the single control surface on a wing known as the aileron also acts simultaneously as a flap, is called a FLAPERON. 😉👌
Lift is very easy to explain. It's caused by a pressure difference between the upper and lower surfaces of the wing. Explaining why that pressure difference occurs... that's the hard part.
Nope. Has nothing to do with the pressure differentials. It exists but doesn't cause lift. High lift/drag devices like fowler flaps and slots disprove this. It's all about lift as a force. F=MxA. Mass off the aircraft, the air itself and the relationship of the acceleration of everything. The navier-stokes equation is right now the prevailing theory and disproves equal transit and pressure differential as the cause of the force of lift.
@@AFO3310 The only mechanisms that a fluid like air has to act on a body are pressure normal to the surface and frictional forces parallel to the surface. Pressure forces are typically much higher than frictional forces so they dominate the result when you integrate over the surface. Slotted flaps don't change that. In fact, I'm curious what you think slotted flaps do.
As an engineer by training, and an aviator (soon to be flight instructor), I find these discussions interesting and fascinating. And Mr. Machado, you hit the nail on the head, when you stated _"to understand how lift is produced, one needs to understand conservation of mass, momentum and energy",_ and of course, the equations behind them. It's almost similar to, when people with no scientific background ask "What is Schroedinger's equation?" or "What is the Heisenberg's uncertainty principle?"
As you pointed out, that is *inherently* difficult to explain in "lay terms" if you want to make sure that the explanation is _scientifically accurate._ Unfortunately, most students (and flight instructors) are not in advanced physics or engineering courses, and that makes the simplifications necessary, to explain these things in a QUALITATIVE fashion. And consequently, that makes the debates and arguments people have, meaningless, for the aforementioned reason!
Thank you for that very nice comment, Captain. I sure do appreciate it.
Best,
Rod
Thanks for the explanation! It's the first time I see a mention of the difference due to the column of air height, isn't that negligible in comparison? It's a few cm vs tens of thousands of feet of air.
Rod. Riddle me this What causes the window on my 180 to stay glued to the bottom of the wing. Is it accelerated air creating a low pressure close to the bottom of the wing????
Thank you very much
Small Pixies in the wing and magic, LOL
Hello Rod,
I am wondering if you could share some of your references that you used to gather this information? I am for the life of me trying to find peer reviewed reputable journals or publications explaining lift generation. Specifically why the airflow stays attached to the airfoil, follows its shape in high angles off attack, and increases in velocity.
Thank you!
Greetings Captain:
There are several references that can help here. Perhaps the most important one is Richard Von Mises' "Theory of Flight." This book covers both the circulation and tangential theories I presented in this video. As far as why airflow conforms to the wing's upper cambered surface at normal angles, well, good luck trying to find agreement on that issue. The best (Ocham's Razor) explanation is the "Coanda Effect."
Best,
Rod Machado
As long as the air flow is relatively orderly (non-turbulent), it is rational to assume the force of ambient pressure from above, ensures the airflow stays attached to the airfoil.
The affected airflow mass transit is competing for space with the airfoil. The space along the upper curvature is fully utilized for this air mass transport flow due to the pressure consequences of the competition for available space.
We see this reflected in no variation in mass density.
At subsonic speeds, mass density is constant around the airfoil's pressure and velocities gradients (I believe this is because the average random motion thermal velocity of the air molecules at subsonic speeds is fast enough to relieve any tendency for mass compression through non-enclosed spaces).
Because mass density is constant (no compression to squeeze more mass through a tight space) the only way for the required uninterrupted flow rate of mass to proceed, is through any available space that doesn't produce turbulent disruption.
Ambient pressure ensures this.
explanation starts at 5:19
Imagine you could close off a huge chunk of atmosphere in a closed box. Then place a measuring scale under the box to measure its weight. Then have a plane fly in the box around and around in a circle. Does the weight of the box change?
The scale will now measure the weight of the box and the weight of the airplane. There are good videos on the Internet showing this demonstrated with a small drone.
@@raymondlancaster3355 This is the final debunking of the Bernoulli "explanation" of lift then. Wings produce lift by deflecting air downwards such that the weight of the plane appears as increased pressure on the ground below.
Take a look at this video: ua-cam.com/video/N0IGrSjcBZs/v-deo.html
In my opinion, lift is a consequence of the third law. Bernoulli just explain why the speed change because of the preassure gradient. By the way, I think always the pressure gradient change the speed and never backwards. And the air accelerate on the upper side only on the first part of the wing not allway to the trailing edge.
Those phenomena, like any others in physics, are not one-way: pressure gradient and velocity are coupled by the principle. And enough experiences have confirmed the profile of pressure predicted by the Navier-Stokes equations with a net lower pressure above the wing and higher pressure at the bottom, so it's a valid model.
At the end you said you gave no explanation in terms of conservation of mass, energy and momentum. Yet you hold out hope that maybe we would come to grips with Navier-Stokes?
What is Navier-Stokes, if not conservation of mass, energy and momentum?
If we were to explore what conservation of these concepts means as interconnected by Navier-Stokes, we could hopefully explain why equal transit time as has been described, is really a misreading of conservation of mass transit and its consequences.
Equal mass transit time of the affected air flow is crucial to "simplifying" an understanding of lift.
So instead of retreating from "equal transit time" when we see that the air on top moves faster than air on the bottom, a refreshing explanation would be how equal mass transit is accomplished when the simple "equal transit time" is false.
Why is this reconciliation missing from all the lift explanations?
Why does't the air parcel accelerate on the upper surface with zero degree angle of attack, as experiments shows?
Or
The air parcel must not to accelerate under the wing because of rounded leading edge?
Or the air parcels know that they have to accelerate on the upper surface only? Of course No...
Have you any answer
Greetings Mr. Black Spider:
I'm sorry but I just don't understand what you're saying here.
Best,
Rod
@@shortclips7052
"Actually air particles don't accelerate on the upper surface of the airfoil with zero degree angle of attack..."
That is not correct. Air particles accelerate on both the top and bottom of the airfoil in the condition you describe. No lift is produced in the condition you describe (zero-lift angle of attack assumed here or symmetrical airfoil at zero-degree angle of attack assumed here).
"The speed of air particles on the upper and lower surface is same when the airfoil is not inclined with an angle..... Why?"
This is correct with a symmetrical airfoil.
99% 3rd law, maybe 1% Bernoulli
10:21 Right, I didn't assume the cofounder of the Black Panthers was studying Aerodynamics.
Very simply, a moving wing dumps a starting vortex. There is then vorticity of opposite rotation bound up with the wing, which then generates lift by the Magnus effect.
Not really an explanation though, sure it's one of the mathematical models but why should this happen? It's neither simple nor complete.
@@no_fb I could elaborate on my explanation, but I suspect that you have some odd ideas of you own. What do you want me to do which doesn't involve me wasting my time?
@@no_fb Lift is simply:
1)asymmetry
2)turning the air
if only a bit more detail:
3)from a competition for space caused pressure response
4)which accelerates the air mass sufficiently to prevent flow disruption.
(Conservation of mass, momentum and energy, are the ground rules for how this expediting pressure profile develops around the airfoil.)
@@david_porthouse The air turns due to asymmetry of the airfoil. The magnus effect is simply a way to add asymmetry. It doesn't by itself explain lift.
As already mentioned:
Lift is simply:
1)asymmetry
2)turning the air
if only a bit more detail:
3)from a competition for space caused pressure response
4)which accelerates the air mass sufficiently to prevent flow disruption.
(Conservation of mass, momentum and energy, are the ground rules for how this expediting pressure profile develops around the airfoil.)
@@davetime5234 A symmetric aerofoil like NACA0012 can generate lift quite well.
13:32 the air particle starts to fortnite dance.
I've used,, has have the instructors I work with, the simpler version even though I knew it wasn't "correct". You've given me words to use for what I already knew to be true. Thanks.
Thank you, Scott. I sure do appreciate the comment.
Best,
Rod Machado
Perfectly flat wing produces lift .....
The Mystery of Airfoil has been solved !
The reason it took so long to get to the reality of lift was the basic error in assuming there’s some kind of flow of air over the airfoil, which gave rise to various erroneous non-existent and irrelevant concepts e.g. Bernoulli, Flow-Separation,etc. Everything is covered in the book, in detail. The matter was a very simple one, but the wind tunnel gave the scientists true tunnel vision for the past century. Check tekemon.
A waterski has no curved top surface or water flowing over it .
That's right, it looks like maybe it is more analogous to drag sailing rather than lift sailing.
Video starts at 5:20.
No. It's starts at 00:00.
The authors have two wrong scientific approaches: researching the creation of Lift force and Low pressure at upper side of the wing, relative to the ground surface and Earth. I explain the aerodynamic cavitation and existence of Lee side aerocavern, and creation of Aerodynamic force.
🤣🤣🤣🤣🤣🤣
Better question is, WHY is lift so hard to understand? Don't just silently assume that the answer is exclusively "Lifting force is complicated."
Once we attain an extremely deep understanding, the reason instead appears to be, "Many of the explanations are so oversimplified, that they're simply wrong." Analogy: astronauts can float around because all gravity ends at the top of the atmosphere, and there is no gravity in outer space!" Very simple! Some grade-school textbooks actually taught this in the early 60s. Kids can understand it easily, right? So we should all use it as an explanation? Really? (But ...any kids who believed such stuff, would have a serious learning-barrier, and they couldn't later be taught how orbits work, or exactly **why*** the gravity can only exist in air and not in space.) The explanation is simply wrong, rather than just oversimplified. And, if that explanation was widely used, and appeared everywhere, it still would be just as wrong.
So, with any simplified explanation, at the very least we should also mention its limits, always explaining WHAT'S WRONG WITH IT. The "equal transit" explanation fails because it cannot explain thin wings, where the upper/lower path-lengths are the same. It predicts that the Wright Flyer would have zero lift. It tells us that sailboats can never work, thin fish-fins cannot propel fish, and of course if a plane should ever fly upside-down, then the lifting force can only aim downwards at the ground.
See, its real problem isn't with the air molecules having feelings. Instead the problem is that "equal transit" is very much like the "no gravity in space" explanation. It's fundamentally wrong, in other words, it qualifies as misinformation, giving students misconceptions, and ultimately it must be un-learned before the student can be taught any other improved explanation of wings. It forms a flawed foundation, impossible to build anything onto it. Yet it wasn't limited to children's books. It was used for decades in pilot-training, and even was appearing on licensing exams, until a group of aero theorists from Sweden started making a huge stink about it, back in the 1980s. The controversy about "transit-time" only exploded in the early 1990s, when it spread into the piloting newsgroups and RC modelers' newsgroups online. Giant 1994 flamewars! And finally, it all went exponential, when the WWW arrived, and we could actually have photos and diagrams online.
BTW, with the typical "Bernoulli" airfoil diagram ...WHAT'S WRONG WITH IT? What are its limits?
BTW, with the typical "Bernoulli" airfoil diagram, where the flow is entirely in two dimensions, and the "wing" is an airfoil-section ...WHAT'S WRONG WITH IT? What are its limits?
First, the airfoil doesn't deflect any air, on average. Instead, the air approaches the airfoil horizontally, and leaves horizontally. (This is *required* by the physics, as long as we're in a two-dimensional world, and no start-vortex is nearby.)
The airfoil-section first bends the air upwards, then curves it downwards, but then, rather than leaving the air moving down, it next bends the air again, so ultimately the air departs horizontally. No momentum is placed into the air, on average. Huge problem, eh? (But we "solve" the problem by not pointing out that the airfoil bends air upwards as it approaches, and bends air downwards afterwards. Also, we never tell students that the explanation directly violates momentum-conservation!)
Yet with real wings, sailboats, helicopters etc., the deflected air has momentum, and continues moving downwards after the wing has passed by, and if with non-viscous fluids, it would keep moving down forever.
As I said, we should always ask Why is the Bernoulli/airfoil explanation Wrong? What are it's limits. It's wrong because it's actually describing a venturi, and the ground is inescapably part of the system: ground is the second surface involved, where "Lift" is actually an instant-force, a Newtonian force-pair between airfoil and Earth. (But note carefully, that's not how rudders and fish-fins and props and sailboats work, these things aren't "pushing off from" some distant surface. Neither are wings, unless during ground-effect flight.) And, if we erase the ground surface, carefully avoid mentioning it, then Lift in this sort of explanation becomes an illegal "single-ended force," a blatant violation of Newton's 3rd law. Aero-people happily do this, building Newton-violations into the explanations, while even a grade-school physics teacher would sadly shake their head at such tactics, or even throw up their hands and retreat in sheer disgust.
@@wbeaty There are some problems here:
"equal transit explanation fails because it cannot explain thin wings, where the upper/lower path-lengths are the same. It predicts that the Wright Flyer would have zero lift. It tells us that sailboats can never work..."
The transit of affected air mass still must proceed to exit at the same rate it enters the system. That fact needs to be integrated into the explanation.
And such conservation of air mass transit affects any thickness of airfoil as long as it maintains an asymmetrical orientation to the relative wind.
"No momentum is placed into the air, on average."
The above is false. A wing's force of lift is 100% equal to the change in vertical momentum transferred to the air. What you are suggesting violates the most fundamental laws of physics.
"Also, we never tell students that the explanation directly violates momentum-conservation!"
Because you're wrong. There is no violation of momentum conservation.
"Why is the Bernoulli/airfoil explanation Wrong?"
It's not wrong just because you don't understand something.
"It's wrong because it's actually describing a venturi, and the ground is inescapably part of the system"
This doesn't make sense. Even though Bernoulli and venturi are often introduced by explaining it for an enclosed solid, the conservation of energy concept has much more universal application.
In the case of a subsonic airfoil, the mass density of air doesn't change around the airfoil. That means all mass in the system is competing for space without any "compression cheating." So, when the solid airfoil comes along the airflow in its path, in getting out of the way, has to compete with adjacent airflow mass.
The only way to get the same mass flow rate through, is for the speed to increase. The pressure to speed conservation of energy relationship is fully at work here.
So, you have incorrect understanding of transit time, Bernoulli, and venturi.
Rod Machado, Sir, I could not help smiling a little at you pointing out how air moves along the surfaces of a wing and you even go to say that, " We shall explain how WIND BENDING CREATES LIFT" Well Sir, please think more carefully about wings as, IN REAL FLYING WING, ( not a wind tunnel) THERE IS NO WIND, NOR PARTICLES MOVING MUCH ALONG THE SURFACE OF AN AIRCRAFT WING. If mass particles in a wind move horizontally with a horizontally moving wing there will be no lift whatsoever!! In a real wing, it is the wing that moves in the effective stationary mass air particles at an instant of time, around the moving wing, are basically accelerated vertically up and down with a little displacement to the trailing edge on the upper side due to a suction zone and a little displacement to the leading edge on the lower side due to a compression zone. This is the circulation due to such displacement that causes the downwash, which is effectively a VERTICALLY DOWN reaction to a process that occurred before, and it is really not a horizontal wind as you are inferring, Please think deeply about it. Here is how I explain it with my own sense of humor. I hope that you shall enjoy reading this,
It is not wise to keep talking about the air flowing over the surfaces of a wing, as relatively speaking, in reality, the primary effective working air does not move horizontally much over the wings. People have a habit of conducting tests in a wind tunnel where the airfoil stands still while it is the air that is moved at a speed, relative to the stationary wing.
The streamlines as shown at 5:47 need to be understood for, in a wind tunnel, the mass air particles on the streamlines are moving horizontally at high velocity but in the reality of flying, the air is initially standing still, the mass particles are not moving much horizontally but they are being basically displaced vertically with an acceleration which builds up and is integrated twice into a location shown by the slipstreams.
Also, note that the diagram is shown at 5:47 is a POSITION OR A LOCATION diagram and not a velocity diagram. If we had to draw a velocity diagram from it, then one could determine the velo0city vector field consisting of little vectors lined up with the streamlines where the length and direction of the small elemental vectors would represent the velocity in magnitude and direction at any location/time on the streamlines. But if it was a wind tunnel, the velocity vector field would represent the velocity of the air particles, but if it was a real flying wing on a moving aircraft it would be the velocity variations about the speed of the aircraft. From the contour of the streamlines diagram, it appears that the horizontal velocity is basically constant but the curvy zones show a vertical velocity component. So, if from the velocity diagram we would obtain the acceleration vector field, then the acceleration vector would represent the force at that particular point, considering that the acceleration is operating on the mass of the lump of air existing at the location where the accelerating vector exists ( mass is a scalar and can be taken as a constant in this case).
The curves in the streamlines indicate that there are four main acceleration zones in the diagram shown at 5:11.
1.There is a compression accelerating zone just ahead and on and above the upper part of the leading edge.
2. There is a suction accelerating zone after location (1) existing along the upper surface to the trailing edge.
3. There is a suction accelerating zone just behind the lower part of the leading edge.
4. There is a compression accelerating zone existing from location (3) going all the way under the lower surface all the way to the trailing edge.
*** It is the combination of these four zones that basically ACCELERATE the mass fluid particles vertically up and down with a little horizontal ACCELERATION TO THE TRAILING EDGE( upper surface) AND AN ACCELERATION TO THE LEADING EDGE (lower surface)
*** All these four zones are easier seen on a highly cambered very thin airfoil section where the upper surface is the same length as the lower surface. The practical meaning of these pressure /suction zones could be interpreted as follows, which contain the existing Newtonian effects and the Viscosity effects on a moving wing, note moving wing with no winds around. Assume the mass of an air/ fluid particle consists of a fat man holding an opened umbrella. The fat man with mass for the Newtonian momentum effect and the opened umbrella for the viscous effects of suction, compression, shearing, and slipping, sealing, etc.
One fat stationary man, with an opened umbrella, located above the mean line, is hit and pushed up and accelerated up through action ( 1) and the oncoming upper leading edge will shoot the man up, but him holding the open umbrella, a partial vacuum will be created between the area of the umbrella and the surface of the wing and so this partial vacuum will pull down the man and suck up the wing as it passes under the fat man to dump him over the trailing edge using Action (2)
A second fat stationary man, with an opened umbrella, located below the mean line, is sucked up by action ( 3), and then the compression zone through action ( 4) will push the fat man down and the reaction would be a push up on the undersurface of the wing, to dump the second fat man with a delay ( basically vertically down) behind the trailing edge to join the first fat man being dumped from the upper surface behind the trailing edge, a little earlier. Note that in real flying action, the two stationary fat men with the umbrellas are operated upon by the actions indicated in 1. 2. 3. 4. and from the logic and sequence of the actions/ reactions the upper-fat man will have a higher backward horizontal velocity than the lower fat man due to one moving into an upper vectored suction zone due to the downslope of the rear upper surface, and the other moving in a vectored compression zone, which moves the fat man forward and not backward, before both of them are dumped behind the trailing edge, not at the same time.
That is basically how the acceleration vector field around an airfoil section works, and the same goes, for rudders, ailerons, elevators, spoilers, any part of the structure, air, and sea propellers, and ship hull and the diffusers we meet in all aspects of engineering, where accelerations of fluid lumps masses are involved We shall not cover the effect of heating the air or the boiling of water or moisture when the suction is fiercely done.
Note that the vertical acceleration components of the fluid around the wing are what causes total lift and the horizontal acceleration components of the fluid are what causes the total drag.
Lift and drag, and control of surfaces, relative to these actions, all have to do with the acceleration field and not the velocity nor the position fields around the airfoil sections. Note again, that in a wind tunnel the air moves and airfoils standstill, while in reality, the lumps of air move but a little and it is the velocity of the airfoil section that is much higher than what the air reaches after its acceleration is integrated to velocity ....... and then the velocity of the fluid lumps masses are integrated to relocate them from their initial stationary location to dump them as their integrated accelerations, velocity and resulting locations are too far from the wing to be of any use to flying it, but could be disastrous to aircraft.. following in the wake..! ( with drag there are other boundary layer shear to consider)
The explanation of how streamlines return to the upper surface of the wing at 8:25 is not exactly correct as normally, it is this suction zone on the surface of the wing that accelerates the fluid mass "sealed"particles to move back close to the upper surface, the reaction of which is the further generation of the lift even up to the trailing edge. This suction zone is a property of the fluid itself remain in the desired state. Note if the substance above the wing were loose dry sand mass particles without a sealing effect between the sand particles, the wing will not be sucked up! Note this suction zone is effectively the tension, accelerating down the lumped light mass of air above the wing which reacts to accelerating up, the high mass of the wing. This is the reason why the particles of the air gain such a high velocity downwards to be dumped behind the trailing edge. ( note moving wing and not moving particles as in a wind tunnel) The wing at this stage is no more than a wedged piston moving horizontally leaving a suction zone behind it which if we use the diagram at 8:25, the rear part of the wedge-shaped piston will rise up due to accelerating the mass particles down and if the wing is not loaded and without weight, then the rear edge of the wing will be symmetrical about the line of flight.
The suggested explanation by the author of this video applies only when the wing stalls and the suction I mentioned is lost, as the working fluid lost its normal desired state, or when the diagram refers to the water vertical rudder near the surface, of a boat or a ship where when the rudder is angled, air can aerate the rudder and the suction is lost and the water returns as was suggested in the video. I would compare stalling of a wing to a cavitation effect in an immersed rudder, or the blade of a totally immersed propeller, but we shall not go into that boiling property of water or water vapour/moisture above the wing.
So, Newton works underneath the wing, but Bernoulli takes over on top of the wing
Checks out since it doesent make sense that a force that pushes something upwards is coming form the top. Newton is pushing and bernuli is sucking.
It always drives me insane how scientists, engineers, pilots, the gov and literary wanna be’s make such a train wreck out of this topic. And now UA-camrs too! The REAL simple explanation is: Migration (“Lift”) is the right angled drift created by the “directed vacuum and compression” when forward velocity of a solid object is present through the medium. Duh!
Yeah! Good. Whatever that means