Have you tried the "soup-spoon and faucet" experiment (like the one in Jef Raskin's article). If you haven't you should. It's entertaining (for me it was...anyway). Imagine "musket balls" instead of water coming out of the faucet. Would the reaction be the same?



You are still locked into preconceived notions.

Yes.. I've tried the spoon trick. It only shows what happens when there's  fluid flowing accross one surface.

The point of the tube was to ALLOW for Coanda, while simply demonstrating mass redirection and the action/reaction.

(I'm not disagreeing with Coanda or Newton.. just saying that without AoA they can't lift..  Bournelli can)

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Same thing that happens to it when it impacts any bend in the pipe.


I wasn't trying to prove or disprove anything about fluids vs. solids.  The whole tube/ball model was all about N3.. that's it.. nothing more. I was showing that the N3 lift cannot occur without AoA (as opposed to Bernoulli's lift that CAN happen at zero AoA)..

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I'm not sure what you're asking here, but I'll take a stab at it. The AoA depends on the airfoil shape mostly, but also at what angle it's fixed to the mass of the plane.. and from where (what angle) the COG of the plane is acted upon. For example;  A wing cross-section that could be described as an arc greater than 50%  of a perfect circle with continuing tangents that meet at the trailing edge, would have to be fixed to the fuselage with a built in AoA in order for it to produce EITHER type of lift while the plane itself flew along with zero pitch (and could act as a wing providing both types of lift with the plane inverted, so long as the overall AoA (including negative pitch for the inverted fuselage) was positive).

You're overcomplicating things. I've long since accepted that a positive AoA needs to be present. I understand that Coanda and Newton are in play too. They alone could make the barn door fly...

But it's Bernoulli (hope I spelled it right this time) who makes an airplane fly..

Sorry.. lol..  I can't get into overall performance (that's what I meant by overcomplicating).. that get's into stuff that would REALLY show how ignorant we are..

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No worries.. it won't be the first time they've heard that.. (and from people actually qualified to say so (and I remember seeing where NASA themselves (last time I got into this debate and did research) saw my point)  

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Ok.. but if this turns out to be a semantics trap, I'm ready with a response 

I'm certain a wing can be shaped as to lessen the the drag encountered while maintaining the AoA required to yield a net redirection, hence N3 lift.. and that that would lessen the "aparent" lift derived from pressure diifferential..

But I'm also certain that the aerodynamics get so complex at that point, that there isn't a single expert in the world capable assigning proper, proportional "credit" to the lfit. You could probably show a mathematical model favoring anything... and at LEAST show that pressure differential is what's making the redirection more efficient.

The bottom line remains (where I will not cede).. N3 don't happen without AoA..  Pressure differential DO.  It's what makes a wing a wing, and an airplane fly.

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I dunno.. this gets into aerodynamics even MORE beyond the scope I've dared (or should) comment on, to date. I'm sure there are wings that will actually show a L/D spike at some point, as the AoA increases.. After all.. we've already acknowledged that there's a positive AoA in level flight (which I hope would be somewhere near where L/D is at its highest).

The Cherokee/Malibu comparison is interesting. I don't think the Malibu is a constant-chord wing though.. But that aside.. (and assuming, magical, structural integrity) a 140 on the other side of mach just might be more efficent than a subsonic Malibu (you didn't place realistic limits on "enough power"     )

Brett_Henderson wrote on Jan 12^th, 2007 at 6:34pm:


I think you're missunderstanding the designation. A "flat-bottom" wing (their words not mine) is the classic airfoil shape.

The symmetrical wing is the one that flies equally well upside down. (same upper profile whether your...um...up....or not)

We know the reason why all of the latter Pitts have a symmetrical wing. (Pitts pilots like to fly "up-sy-downey" all the time)

I brought up this example because; here you have two, nearly identical aircraft, but one doesn't take advantage of the crucial, inherent pressure differential of an over-cambered  wing.      Yet.......if you study the pictures, you'll see that the change didn't necessitate a drastic angle of incidence. It doesn't seem to need to fly at a rediculous AOA, to make up for the the lack of......vacuum?......and (as stated earlier) it didn't require a massive increase in wing area. Soooo......what was effected (from aircraft A to aircraft B) (or C to S...if you like   )

mmm-kay.....You're still not answering my question.

Maybe it's because I began my aviation life as a grease monkey and not an officially trained engineer. With that said, I tend to approach events with a caveman-ish outlook. "...bolt don't move.....get bigger hammer to remove bolt!"
We know why the latter model is different but what is the tradeoff? Where do you loose out?

Your telling me that the angle of the fuselage will be different (relative to the wing chord).

So the only difference will be a higher wing angle?

The only difference can't be that the "S" model doesn't look as cool because they had to mount that dang low performance, low vacuum wing at some jacked-up angle to make up for it's lack of efficiency can it?

If pressure differential is so crucial, where does the model with the positive camber wing (and resultant greater pressure differential) really show it's stuff?