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"Engineer debunks theory of Flight"
2

"Engineer debunks theory of Flight"

"Engineer debunks theory of Flight"

(OP)
http://www.smh.com.au/world/engineer-debunks-theory-of-flight-20120126-1qjrc.html

i was hoping for something more radical ... he's going back to the old myht that two molecules of air ahead of the wing join up again after the wing, the longer distance of the path over the wing measn it has to travel faster, ...

no, he says it's the shape of the wing causing lower pressure above ...
which from bernoulli means higher speed ...

 

RE: "Engineer debunks theory of Flight"

Let's not bring THAT subject up again.  It was beaten to death a couple of years ago here, when someone brought up the question of circulation.  Moreover, the "professor" is promulgating a myth to "debunk" the other myth.  His "explanation" uses pressure differential to "cause" lift, which, we know, is not correct either.  If he had gone on to conservation of momentum, I might have gotten interested.

TTFN
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RE: "Engineer debunks theory of Flight"

Hang on, is this the clip http://www.youtube.com/watch?feature=player_embedded&v=UqBmdZ-BNig

In the clip all he does is demonstrate that particles going over the top of the wing don't arrive at the back of the wing at the same time as those going under.

However, in the article the talk about curved 'wing' does not match what I was taught, or experiments we got to conduct.

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RE: "Engineer debunks theory of Flight"

It is only the Sydney Morning Herald, which outsources its journalism and editing and printing. Some of the comments underneath are pretty funny (No my pen-name isn't John Shaw from Melbourne)

 

Cheers

Greg Locock


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RE: "Engineer debunks theory of Flight"

Well yeah, I was only going by the part in quotation marks, which I vaguely hoped was at least from the prof.  Now it may be out of context but unless they really changed the wording or made it up then it doesn't look good.

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RE: "Engineer debunks theory of Flight"

I also was taught the "faster top - slower bottom" theory in uni.
I also vaguely remember one of the profs mention that the lift may have to do with the coefficient of drag at certain angles of attack. The higher the drag the more momentum is displaced. Then the lift can be derived from there, possibly.  

peace
Fe (IronX32)

RE: "Engineer debunks theory of Flight"

(OP)
that's cause it is "faster on top", 'cause the static pressure is lower.  the problem with the two molecules meeting up again is that i think it is a simplification for the masses.

RE: "Engineer debunks theory of Flight"

The faster implies a lower pressure, so it boils down to whether the pressure differential is enough to lift the plane.  If it isn't, then that theory is wrong.

TTFN
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RE: "Engineer debunks theory of Flight"

Well, I was taking for example the demonstration of the pulsed smoke plumes - where that over the top clearly reached the rear of the wing before that going under the wing - as a reasonable indication that the air over the top is effectively traveling faster than that under.

So hence I'm pretty confident in the 'theory' that air over a lifting wing is traveling faster than that under it.

This was in response to FeX32's comment.

I wasn't getting as far as applying Bernoulli, and definitely wasn't straying into conservations of momentum or bound vortex territory etc.

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RE: "Engineer debunks theory of Flight"

Hell Yawll aint getting it, yonly get lift if th wing deflects air down equal to the weight of the plane an it don matter how it does that.thumbsup

The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them.  Old professor

RE: "Engineer debunks theory of Flight"

Horses, dead, beating.

RE: "Engineer debunks theory of Flight"

Quote:


So hence I'm pretty confident in the 'theory' that air over a lifting wing is traveling faster than that under it.

I'm not disagreeing with the theory. I would just feel more comfortable if we could relate it to a differential change in momentum somehow.
Anyways, I don't want to beat any horses to death, what did they ever do to us besides provide us with ample transportation for centuries.

cheers

peace
Fe (IronX32)

RE: "Engineer debunks theory of Flight"

(OP)
Horses, Dead, For the Beating Of ...

RE: "Engineer debunks theory of Flight"

glue? lol smile

peace
Fe (IronX32)

RE: "Engineer debunks theory of Flight"

Ok, the glue and French cuisine went right over my head lol

peace
Fe (IronX32)

RE: "Engineer debunks theory of Flight"

Well, dead horses have never been much for providing transportation.

At times in the not so distant past they did form the raw material for certain glues (or at least parts of them did).  http://en.wikipedia.org/wiki/Animal_glue

The French also eat Cheval.  http://en.wikipedia.org/wiki/Horse_meat

How short are you FeX32?   

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RE: "Engineer debunks theory of Flight"

haha. Nice KENAT. Thanks.
I am not a large man. Only large in some ways wink. I am average height I would say. lol

peace
Fe (IronX32)

RE: "Engineer debunks theory of Flight"

Yea, and if I ever start to tip over I always have my third leg to prop me up.  

peace
Fe (IronX32)

RE: "Engineer debunks theory of Flight"

KENAT,

   The wing in your video looks symmetrical to me.  

   If the wing were asymmetric and the angle of attack were zero, I think there would be a higher velocity and lower pressure on top of the wing.  Also, the air coming down from the top would have more energy, causing the air to be vectored downward, which is of course, the other explanation for airplanes flying.  

   Beating a dead horse does not cause flight as far as I know.   

               JHG

RE: "Engineer debunks theory of Flight"

Isn't lift something to do with vortices?  

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