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yuri_base

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Any serious development will try to collect as many data as possible.



Do you have data for lift and drag as functions of angle of attack?

And if yes, can you share it?
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Agreed

Maybe we need to look again at the whole concept of vortex lift.

At high angles of attack. sharply-swept wings lose laminar flow over their top skins and they act like a giant wing tip, which generates one massive wing tip vortex.
The disadvantage of vortex lift is that it also generates massive amounts of drag.
For example, when the Concorde came in to land, it had to fly at high angles of attack to generate sufficient lift at low airspeeds. Those hish angle sof attack generated so much drag that they also had to apply lots of power to maintain a survivable rate of descent. Ergo, the public complained about Concordes being too noisy on final approach.
Also remember that Concorde pilots needed extensive training in flying behind the power curve, because it was possible to get so low and so slow, that you were doomed. IOW it was impossible to "power"' your way out of a bungled approach.

Maybe we need to look again at vortex lift on slightly-swept wings like Withold Kasper did back in the late 1950 and early 1960s. See BKB sailplane and Kasper unltralight. Both airplanes used long, vortex-control panels along their leading edges to stabilize vortexes. ... sort of like high-aspect-ratio versions of the deflectors installed on tail wings.

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Do you have data for lift and drag as functions of angle of attack?
And if yes, can you share it?



No, I don't have data for lift and drag as functions of angle of attack but I have data for pracitcal usefulness as a function of narrow angle of view.

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Rob,

Last night on history channel there was a show on the P-51 mustang fighter plane. In the wing design they said that to reduce drag and air stacking on the leading edge they thickened the wing profile in the mid-rear (not leading) part of the wing. Do you have a better explanation of this?
"The evil of the world is made possible by nothing but the sanction you give it. " -John Galt from Atlas Shrugged, 1957

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Mustang wing was designed for much higher speed (landing speed of Mustang is about 100 knots as I recall).
Therefore it you can not compare it...



>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

They were talking about LAMINAR airfoils.
Laminar airfoils have an advantage at higher airspeeds, up near the speed of sound (around 770 miles per hour).

Most of the early airfoils are thickest at about 25% of Mean Aerodynamic Chord (aft of the leading edge). This forces air to climb steeply over the first 25% of the leading edge. Ergo, most of the lift is generated by the first 25% of the wing.
Laminar flow wings are thickest more like 40% MAC. This means a more gradual change in pressure and lift is generated over a larger surface. This gradual change in pressure really only becomes helpful when you get close to the speed of sound. By delaying the onset of shock waves (by a few miles per hour) the Mustang gained an advantage when diving in dogfights. While P-38 Lightnings and P-47 Thunderbolts struggled with compressibility and controls locking up, P-51 Mustangs were still in the fight a few miles per hour faster than anything else in the skies over wartime Germany.

The downside of laminar airfoils is that they require much tighter quality control (read heavy and expensive) and they are very sensitive to contamination by insects or water.
I do not know of anyone who has made a laminar airfoil work on a fabric-covered wing.

Landing speed is primarily a function of wing area, a totally separate variable.

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Landing speed was just indication in comparison to speed we have with wing suit.
I would say that Mustang wing was quasi-laminar wing, maybe first real attempt to have laminar flow.

In short - very different animal than our wing suit wings.

Boris

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They were talking about LAMINAR airfoils.
Laminar airfoils have an advantage at higher airspeeds, up near the speed of sound (around 770 miles per hour).


The downside of laminar airfoils is that they require much tighter quality control (read heavy and



I never heard that laminar flow foils only provide benefits at higher speeds, in fact they are the foils used on several high tech sailplanes and some early homebuilts, but in both cases surfaces made of fiberglass or graphite where its easier to control manufacturing tolerance.

You are right about surface contamination in some cases if the moisture in the morning air was bad enough to form big droplets the foils lost lift and these gliders could not stay aloft.

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They were talking about LAMINAR airfoils.
Laminar airfoils have an advantage at higher airspeeds, up near the speed of sound (around 770 miles per hour).


The downside of laminar airfoils is that they require much tighter quality control (read heavy and



I never heard that laminar flow foils only provide benefits at higher speeds, in fact they are the foils used on several high tech sailplanes and some early homebuilts, but in both cases surfaces made of fiberglass or graphite where its easier to control manufacturing tolerance.

You are right about surface contamination in some cases if the moisture in the morning air was bad enough to form big droplets the foils lost lift and these gliders could not stay aloft.



Correct - the primary advantage of laminar flow airfoils is in reduced drag due to delaying the onset of a turbulent boundary layer. It does this by having the max thickness farther back than usual so the pressure gradient (Bernoulli theorem) is favorab;e for a greater fraction of the chord. My Mooney has a laminar flow wing, and it's not anywhere near supersonic.

Generally the low drag regime is limited to a small range of AoA values, which is OK for level cruise flight.
...

The only sure way to survive a canopy collision is not to have one.

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There are two areas in wingsuit flight that laminar flow is ALMOST acheived.
one is in a steep AOA dive there is a point when instead of going exactly on the angle you are pointing you drift more forward(as if you are pulling out of the dive) this is an increase in lift being created (this only works well on a wing with a leading edge shaped better than your arm)
I realize this when I am jumping with Ryan Scarlett who weighs over 300 out the door. when he is flying along he is level with the horizon and I am at a much steeper angle but we are both flying the same path though the sky.
at this AOA there is air flowing over the top of my suit I know this because I can feel the air on the belly of my suit (I am backflying in this example, of course)

The other time I have experienced this is (again while backflying) I fly up underneath someone, both flying at a high forward speed and when I get into an exact spot at an exact speed i get pulled up into them (they are not falling on me)
This is due to air being forced over the top of the wings creating more lift.
This is similar to the ground effect planes get flying close to the ground but not exactly the same.

Basically the air separates farther back along the wing than normal not quite laminar.

So here you go yuri your future wingsuit the "BI"plane cause I heard you swing that way

:);):P:P:ph34r:


Don't be mad you haven't given me any slack lately and I miss it.:P
BUY A WINGSUIT
My Website
Tony Suits
[url "http:/

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Jeff, are you saying that when flying in close proximity to someone above you you get more lift? Do they get more lift as well or get sucked down (even when not in your burble)?

If you build a tight 20-way vertical stack, will it fly at 7:1 glide ratio?

One thing is for sure: it'll look very much like Maxim's plane. ;)
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There are two areas in wingsuit flight that laminar flow is ALMOST acheived.



No there aren't.

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one is in a steep AOA dive there is a point when instead of going exactly on the angle you are pointing you drift more forward(as if you are pulling out of the dive) this is an increase in lift being created (this only works well on a wing with a leading edge shaped better than your arm)
I realize this when I am jumping with Ryan Scarlett who weighs over 300 out the door. when he is flying along he is level with the horizon and I am at a much steeper angle but we are both flying the same path though the sky.
at this AOA there is air flowing over the top of my suit I know this because I can feel the air on the belly of my suit (I am backflying in this example, of course)



No. That's still a profound misunderstanding of what laminar flow is. Laminar flow is not just "air flowing over the top of the wing".

IMO, laminar flow will never be achieved with wingsuits and talking about it is a pointless irrelevance.

(Hint, look at a P-51 Mustang wing. It was designed to have laminar flow, but usually did not achieve it because of manufacturing inconsistencies. Compare the relatively near perfection of a P-51 Mustang wing with the general rubbishness of a skydiver wearing a wingsuit and rig. Realise why talking about Laminar flow over wingsuits is silly.)
Do you want to have an ideagasm?

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Please reread

There are two areas in wingsuit flight that laminar flow is ALMOST acheived.
I capitalized ALMOST for one.

Then finished with:
Basically the air separates farther back along the wing than normal "not quite laminar."

No. That's still a profound misunderstanding of what laminar flow is. Laminar flow is not just "air flowing over the top of the wing". CORRECT

Laminar flow is the air not becoming detached from the surface.
Most plane's need the air to detach from the wing surface to get better response to the control surface areas.
After it detaches it now reattaches with more force, getting more pressure on control surface areas.

And my friend Yuri perhaps if you get 9 of your "friendly male friends" to do a stack you will be flying higher than you ever dreamed and not have to leave the ground.;);););):):P:P:ph34r:
BUY A WINGSUIT
My Website
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[url "http:/

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There are two areas in wingsuit flight that laminar flow is ALMOST acheived.
I capitalized ALMOST for one.




Almost achieving “laminar airflow over wingsuit” reminds me of a joke when some guy was bragging that he “makes love almost every day!”

He said: “I made love almost on Monday, almost on Tuesday, almost on Wednesday,…”

Airfoils that are closest to achieving laminar airflow are used on the wings of open class gliders (costing number of hundreds of thousands $ or EUR).
Compare them with the airfoil on the wingsuit.
I think that it requires very extensive imagination to see any similarity between the wing and airfoil on the wingsuit and the wing and airfoils on open class glider.
Laminar flow on non rigid wing is illusion.

Boris

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Forget about stacks, they look too Maxim!

If you can train your 70 horny men of questionable orientation to hold their hands and form a superlong flying wing, the vortices rolling from the wingtips will cancel each other and you essentially get a giant aspect ratio with L/D = 70:1! You'll be able to circle Lake Elsinore from sunrise to sunset catching thermals and land the whole formation without those stupid chutes.

420 foot wide connected formation with amazing glide ratio... now THAT'S a REAL world record!
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There are two areas in wingsuit flight that laminar flow is ALMOST acheived.
I capitalized ALMOST for one.




Almost achieving “laminar airflow over wingsuit” reminds me of a joke when some guy was bragging that he “makes love almost every day!”

He said: “I made love almost on Monday, almost on Tuesday, almost on Wednesday,…”



I was trying to think of a good way to say that - I think you cracked it:)
Do you want to have an ideagasm?

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There are two areas in wingsuit flight that laminar flow is ALMOST acheived.
I capitalized ALMOST for one.




Almost achieving “laminar airflow over wingsuit” reminds me of a joke when some guy was bragging that he “makes love almost every day!”

He said: “I made love almost on Monday, almost on Tuesday, almost on Wednesday,…”



I was trying to think of a good way to say that - I think you cracked it:)



9 is almost more than 10
...

The only sure way to survive a canopy collision is not to have one.

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to heffro:
dude you are talking about the flow still being attached to you (attached vs detached) both laminar and turbulent flows are attached.

now to everyone:
no offense or anything but im pretty sure 90% of us should go take an aero engineering refresher course, or an intro before we continue on in this discussion. arguing about it on the internet is pretty much teh worst way to learn it ever.

there are some people that understand it correctly, but you can't teach someone aero on dorkzone.
word to your mother,
RJ$$
BASE 1117

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I think we don´t have to know anything about aerodynamics to fly. Just fly and enjoy it. Birds don´t know about aerodynamics and they still fly very well. And I am pretty sure that birds enjoy flying a lot. Otherwise they would walk...;)
- No mercy in the flock! Straighten your legs!!! -

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I realize this when I am jumping with Ryan Scarlett who weighs over 300 out the door. when he is flying along he is level with the horizon and I am at a much steeper angle but we are both flying the same path though the sky.

:P



Ryan is obviously staying aloft under the airdynamic rules of the lifting body. Were they design the longer curvature of the foil on the bottom instead of the typical top of the foil.

I could spam this thread with an ass-load of useless math and dead end links but I don't hate anybody on these forums nearly enough to do it.

But if you care you can do a search of lifting bodies or flying bathtub and you will see some cool stuff! Two minute flights from 12,000 feet kind of stuff. Specially you Ryan. Tubbers can fly too!:D

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the pitch angle for best glide is below the horizon



wrong assumption. no suit fly below the horizon



What is your pitch angle when you fly for max L/D?
Android+Wear/iOS/Windows apps:
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iOS only: L/D Magic
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[. My Mooney has a laminar flow wing, and it's not anywhere near supersonic.




Your mooney only has laminar airfoils so that the fuel tanks don't leak.;) Which model is that? How are the tanks? Got the bladders installed? One of my favorite X-country gen airframes BTW.



Hmmm - clearly someone familiar with Mooney gas tanks. Yup, that laminar flow wing keeps the gas in the right place.
...

The only sure way to survive a canopy collision is not to have one.

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thats clearly not what i meant.

i enjoy flying, and i don't need to understand the aerodynamics of it to do so.

however to have a sensible discussion of aerodynamics. a brief knowledge of the terms and forces involved makes it tremendously easier for everyone else to understand you.
word to your mother,
RJ$$
BASE 1117

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