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New theory on how planes fly.


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Hi,

 

If you’ve ever wondered whether the official explanation of how planes fly (as taught to pilots), is BS, well it is. In fact, it’s total BS. There’s no proof for it. None.

 

I show that planes stay airborne based on the same principles as how birds fly; by pushing enough air downwards. See:

 

How airplanes stay airborne - SUMMARY; by N Landell.

 

https://www.youtube.com/watch?v=8yw81t7N6vY

 

(11 minutes)

 

(If you have a problem with the link, just search youtube for the title)

 

There’s also a longer more technical video:

 

How planes stay airborne - FULL

 

https://www.youtube.com/watch?v=VtrYHgBubvY

 

(37 minutes)

 

I’ve asked the CAA, FAA, EASA, Boeing, Airbus, flying instructors, aerodynamics professors, aviation engineers, … and none had any proof. No proof, then the theory is wrong. The CAA don’t know how planes fly. If you have the proof, I’d love to hear it.

 

After 100 years of aviation this should be a piece of cake for the FAA / CAA. Really, how hard can it be to prove how planes fly?

 

I hope that you find this interesting and useful.

 

regards

 

Nick

 

---

 

 

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There's lots of theories on how planes fly, and while the video may have it's merits, your comments have a couple of obvious flaws.

 

CAA, FAA, CASA and so on, are in the business of proving planes DON'T fly, and spend most of their time making sure this happens!035_doh.gif.37538967d128bb0e6085e5fccd66c98b.gif007_rofl.gif.8af89c0b42f3963e93a968664723a160.gif008_roflmao.gif.692a1fa1bc264885482c2a384583e343.gif

 

On the other hand, Boeing, Airbus, Beech, Piper, Cessna, etc know the other theory that it is really MONEY that makes planes fly, (something about how money continually inflates, so it rises naturally..?), that's why they take some much of it.072_teacher.gif.7912536ad0b89695f6408008328df571.gif036_faint.gif.544c913aae3989c0f13fd9d3b82e4e2c.gif

 

 

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The arguments about how planes fly are kind of like arguments about whether cars move due to power of the engine, torque at the driving wheels, friction between the tyres and the road or Newton's laws of motion. With each one you are just analyzing from a particular point of view - you are not excluding the others.

 

The reason why there are arguments is that it is almost invariably taught by people who don't understand it in the first place.

 

 

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I agree with the theory laid out in the video. Although i would say the greater force for flight is pushing air downward, the upper curvature also plays some significance. The greater power the craft has the lesser wings come to play. Think of a rocket?

 

 

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I reckon it's a combination too. I look at my fabric covered (low) wings as I'm flying and it's apparent the fabric is being "sucked" up. I do believe the mass displacement theory is where most of the lift comes from though.

 

 

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I reckon it's a combination too. I look at my fabric covered (low) wings as I'm flying and it's apparent the fabric is being "sucked" up. I do believe the mass displacement theory is where most of the lift comes from though.

It's not a combination - THEY ARE THE SAME THING.

 

100% of the lift comes from mass displacement - that is what Newtons laws say, and there is no way around them.

 

The mass is displaced because of pressure changes around the wing - higher pressure below and lower pressure above.

 

Bernoulli tells us that if we change the pressure, the speed must change, and if we change the speed the pressure must change. Changing the speed of the air is exactly what produces lift according to Newton's laws.

 

Bernoulli is talking about energy, Newton about momentum. You don't have either energy or momentum, you have both. Measuring only one doesn't mean that the other ceases to exist.

 

 

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This is a strange mess of entirely unsupported assertions and frighteningly fashionable 21st century binary 'logic': it doesn't look white to me therefore it must be black. See, I proved it!

 

Next, we'll be told it's the hot gases squirting out the back of rockets that make them go forward; and that hot air balloons go up because 'heat rises'.

 

 

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Hey! How come the Aussie lady who begins the lecture (apparently the author of this, ahh ... new theory, given that she addresses us in the first person) gets replaced by a British voice when it comes down to the, ... the "molecular" level.

 

(The plot gets more complicated when she, in turn, is replaced by yet another woman. Did she jump or was she pushed?)

 

Anyway, I take it - with some umbrage, it must be said - that Aussies don't trust themselves down at the molecular level.

 

But I do appreciate that it's our very own Sheila who finally returns with the zinger "... it's no wonder so many planes crash" (because so few pilots have seen and liked this video). LOL.

 

I did like the 'BS meter' though. Can't knock self awareness. But so much work has gone into this video for ... really, how much fun? The joy of it's got to get trollsome pretty quick. Go figure.

 

At least in bringing up the subject - joke or not - this notable wee self-improvement vid reminds us of an interesting historical point:

 

Jay Spenser, "The Airplane" Smithsonian Books. pp. 130

 

"Aviation's early pioneers never knew how a wing achieves flight.

 

They also didn't care.

 

The simple fact that wings worked meant people could fly by following nature's lead.

 

In this sense, engineering, not science gave us the gift of wings.

 

Pascal, Bernoulli, Euler and others laid down a body of theory to help explain the behaviour of fluids, air included, at rest or in motion. However, that knowledge did not play a role in solving flight's challenges. Instead, science's role was initially to explain the underlying physics of flight after the fact."

 

We all know that the "longer path" over the upper surface theory has long been demoted. As Jim Davis puts it in his 'PPL' textbook (2006. pp 21) 'The war is over' as far as that argument goes. (Until now it seems ;-)

 

He then proceeds to what a pilot really needs to know in order to fly. Stuff the pioneers had to work out themselves.

 

He also links to the NASA website where the old theory is officially and finally (until now) debunked:

 

https://www.grc.nasa.gov/www/k-12/airplane/wrong1.html

 

 

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But both theories ignore the self evident fact that an aeroplane has to generate its own weight in paperwork before it can fly.

 

Bruce

 

 

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OK, here's another theory.... a) air is not `flowing' anywhere, least of all over the wing, b) any molecules involved are just moving more or less perpendicular to the wing surface.

 

rgmwa

 

PS. That's just my opinion. And as Groucho Marx said, "if you don't like that one, I've got plenty more!"

 

 

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We all know that the "longer path" over the upper surface theory has long been demoted.

The longer path theory was just someone who didn't understand Bernoulli trying to explain Bernoulli.

 

 

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100% of the lift comes from mass displacement

if we change the pressure, the speed must change, and if we change the speed the pressure must change. Changing the speed of the air is exactly what produces lift

Well that's interesting.034_puzzled.gif.ea6a44583f14fcd2dd8b8f63a724e3de.gif

You just contradicted yourself. 033_scratching_head.gif.b541836ec2811b6655a8e435f4c1b53a.gif

 

The concept of mass displacement relies on moving (or changing the direction of) mass to use (as you said) Newton's laws.

 

The change of direction is caused by the airflow turning around the curve of the wing, or deflecting off the lower side, if you believe that theory.

 

There would be no need for any pressure changes to occur, to uphold this theory.

 

On the other hand, if it's all done with pressure changes as generated by making air travel over dissimilar distances, then lift can be created without the need of angle of attack. 040_nerd.gif.a6a4f823734c8b20ed33654968aaa347.gif

 

If you look at most of the airfoil data around, you will find lift still being generated by sections running right down to NEGATIVE angles of attack!

 

Now I'm not going to say it's only ONE theory that's involved in the generation of lift, I believe that it is a combination of ALL factors that make planes fly.

 

Of course, none of these theories apply to helicopters, they just rely on the fact they are so ugly, the Earth repels them. :rotary:[/i]

 

 

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OK, here's another theory.... a) air is not `flowing' anywhere, least of all over the wing, b) any molecules involved are just moving more or less perpendicular to the wing surface.

There's a lot of merit in this concept.

Everyone looks to wind tunnel testing of airfoils to crunch out figures of lift coefficients and drag, etc, but the problem I have with this is that the air in a wind tunnel is moving!

 

This air has energy, and can create effects caused by how it interacts around things.

 

In real life, the air is stationary, the wing travels through it, and for the split second that the wing and air interact, ALL this lift and drag and stuff is produced?034_puzzled.gif.ea6a44583f14fcd2dd8b8f63a724e3de.gif036_faint.gif.544c913aae3989c0f13fd9d3b82e4e2c.gif

 

What the ?

 

 

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There would be no need for any pressure changes to occur, to uphold this theory.

You need to ask the question "what is pressure?"

 

Pressure is what we call the overall effect of air molecules bouncing off each other and various surfaces according to Newton's laws. Pressure is just Newton's laws working at molecular level in a fluid. They are one and the same.

 

When we say that we have a lower pressure on top of the wing, we mean that the overall forces from Newton's laws of air molecules bouncing off the top of the wing is less than the bottom of the wing. This is caused by the air flowing around the shape of the wing.

 

you will find lift still being generated by sections running right down to NEGATIVE angles of attack

But there is a pressure change ahead of the wing and you will find that the actual airflow around the wing behaves as if the wing had a positive angle of attack. (Genuine question: can a supersonic wing produce lift at a negative angle of attack?)

 

In real life, the air is stationary, the wing travels through it

Motion is relative, it just matters that the air is flowing relative to the wing. A wing works the same way when the aircraft flies at 100 knots airspeed into a 100 knot headwind and 100 knots airspeed in still air. It doesn't matter which is actually moving.

 

 

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Motion is relative, it just matters that the air is flowing relative to the wing. A wing works the same way when the aircraft flies at 100 knots airspeed into a 100 knot headwind and 100 knots airspeed in still air. It doesn't matter which is actually moving.

Apparently not so. In F1 and CART racing some years ago a couple of clever fellows decided to simulate the car moving through the air rather than vice versa and made startling discoveries that left their opposition well behind so now they all test with that thought foremost.

 

Here's a one of the ways it was done before computer simulation ..

 

http://www.roadandtrack.com/motorsports/features/a24696/racings-secret-hideout-ganassi-tunnel/

 

 

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There are so many theories and experts including Bernouli, Newton and the bloke who lives down the road but the real answer that no-one can deny is simply MAGIC. The following highly technical high definition scale drawing created by a Magic expert proves this to be correct.

 

How_Planes_Fly__Medium_.jpg.93940cc52f79ba74ea54a291b3bd164e.jpg

 

So there you have it. A perfectly logical explanation that even the person with fewer than 2 brain cells available can understand.

 

 

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"In F1 and CART racing some years ago a couple of clever fellows decided to simulate the car moving through the air rather than vice versa. . ."

 

It's a bit different when wind tunnelling road going vehicles. The errors arose because in a wind tunnel the airflow was moving relative to the road surface, as well as the body of the car.

 

In real life (nil wind), there is no relative movement between the air & the road. Hence no boundary layer drag, etc.

 

This situation does not apply in testing airborne bodies.

 

Bruce

 

 

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It's a bit different when wind tunnelling road going vehicles.

You are concentrating on one aspect of it only.

 

In the late 70's early 80's there was a call for aerodynamicists to go to F1 and Sports Car racing, now F1, WSC and other major teams now often consult to the aerospace industry.

 

 

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Apparently not so. In F1 and CART racing some years ago a couple of clever fellows decided to simulate the car moving through the air rather than vice versa ..../

good practice in wind tunnel tests to have a moving ground board for ground effect

The Bernouli theory gets lost when you flip your Decathlon over and fly upside down.

nope, Bernoulli is exactly right, the only problem are those who misrepresent his theory
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This is one topic that annoys me a lot as an engineer.

 

First thing I want to say to pilots is "stop trying to understand how a plane generates lift at an engineering level". What you have been taught is bullshit, and its not necessary.

 

Second, to the pilots who say there is no proof, well look at what you do for a hobby/living. I would say the fact that a plane is in the air, and can be put in the air repeatably is scientific proof that its possible. If you disagree with that proof, then please show me that planes do not fly.

 

When I first started flying, I was told to read the book stick and rudder, and the author nails is perfectly. The reason a wing produces lift is because its deflecting the wind downward. Stick your hand out a car window at speed and you have the perfect example. That and a little Bernoulli WRT to stall characteristics of wings is all that is needed so you can understand how a stall horn works. I only watched a little bit of that video (its also laced with bullshit) but I think the author is pushing that same concept. I hate plagiarism, and the credit needs to go to the author of stick and rudder (just looked it up on Amazon, Author is Wolfgang Langewiesche)

 

As for the engineering side, no one use Bernoulli or Newton exclusively, they use many different theories/models including many which most pilots would never even be privy to in ground school. Whilst I dont do aerodynamics (although I did touch on it at uni, and spent a lot of study time with an aeronautical engineer), I have spend countless hours with other engineers making instrumentation to measure various aspects of fluid dynamics. Engineers know how planes fly, thats how engineers design planes that fly.

 

I read here a lot, but I remain silent because as a low hour (just recent) PPL I probably dont get the credit that a 20,000 hour CPL or ATPL would. But I do understand the basic physics of flight, and I often see those 20k hour pilots regurgutiating that same bullshit they were taught and its plain wrong. When I did my PPL theory, I wanted so bad to point out incorrect information that is taught and tested, but I cant, because I had to be tested on the same rubbish.

 

 

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good practice in wind tunnel tests to have a moving ground board for ground effectnope, Bernoulli is exactly right, the only problem are those who misrepresent his theory

Perhaps I should have said the problem with the Bernoulli theory as presented by CASA doesn't work for the upside down aircraft. Basically, it's complex and in the end you don't need to know the theory to fly an aircraft. The following is from NASA who know a thing or two about lift.

The real details of how an object generates lift are very complex and do not lend themselves to simplification. For a gas, we have to simultaneously conserve the mass, momentum, and energy in the flow. Newton's laws of motion are statements concerning the conservation of momentum. Bernoulli's equation is derived by considering conservation of energy. So both of these equations are satisfied in the generation of lift; both are correct. The conservation of mass introduces a lot of complexity into the analysis and understanding of aerodynamic problems. For example, from the conservation of mass, a change in the velocity of a gas in one direction results in a change in the velocity of the gas in a direction perpendicular to the original change. This is very different from the motion of solids, on which we base most of our experiences in physics. The simultaneous conservation of mass, momentum, and energy of a fluid (while neglecting the effects of air viscosity) are called the Euler Equations after Leonard Euler. Euler was a student of Johann Bernoulli, Daniel's father, and for a time had worked with Daniel Bernoulli in St. Petersburg. If we include the effects of viscosity, we have the Navier-Stokes Equations which are named after two independent researchers in France and in England. To truly understand the details of the generation of lift, one has to have a good working knowledge of the Euler Equations.

 

 

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