# Which aircraft had laminar flow wings?



## spicmart (Sep 9, 2016)

There are many planes known to have laminar flow wings like the Mustang, Sea Fury, Hornet, Raiden etc.. Yet there are some I've never heard to have them but if you look at pictures one could think that they feature them.
E.g. the Mosquito, the B-26 Marauder, some russian and japanese fighters.
Their wing leading edge is sharper and not as round as those of planes like the 109, 190 Corsair etc.. Also the maximum wing thickness seems to be further aft. Might this be an indication if laminar flow wings?


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## Shortround6 (Sep 9, 2016)

Not really. Most "conventional" wing profiles had the max thickness at around 30% of the cord. it could vary a bit but that left an awful lot of "room" for variations in thickness of wing for the profiles. Like one wing could be very near max thickness at 20% cord and another with the same max thickness in actual numbers at 30% (the same location) but use more taper getting there so at 20% it is thinner. It could very well look different but it is not a laminar flow wing.
Now before we get bogged down in what is laminar flow and what is not and NO wing outside a laboratory maintained laminar flow over the whole wing. 
In General a laminar flow wing kept the airflow over the wing from going turbulent for another 5-15% of the cord than the normal airfoils. perhaps even as high as 20%. Many airfoils could keep the airflow smooth (laminar) for the first 5-15% of the cord.

a few extreme examples 





Please note that airfoil #3 was quite common on WW I biplanes. WHile it gave high lift at low speeds and was thin as measured in percent it was not only high drag but often had a bad stall.

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## Balljoint (Sep 9, 2016)

Agree with what’s been said. However, a wing is “more laminar” if the thickness portion is further back on the wing, i.e. so that the airstream has positive contact with the wing. Also, once the wing starts to fall away from the direction of the airstream, the Coanda effect can be enhanced by tripping the air flow to set up a turbulent boundary layer. 
 
As long as the airstream is “attached” to the wing, i.e. flying rather than stalling, it would seem that the flow is more or less laminar, i.e. organized and parallel. Perhaps someone with some actual knowledge can comment on this.


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## pbehn (Sep 9, 2016)

Laminar Flow Airfoil

Some interesting stuff on the above link.

N.A. designed the mustang to be low drag the wings may have been designed to be laminar flow but from what I have read this was not achieved it requires surface cleanliness and smoothness not achievable on a combat aircraft in service. The whole aircraft was designed for low drag especially the close to zero cooling drag radiator, the whole plane was built to very fine tolerances to cut down drag at joints etc even the engine could be termed low drag as it had a lower profile than the early Merlins.

from the above link (which surprised me) 
The Consolidated B-24 Liberator "Davis" airfoil was also a laminar flow airfoil, which predates the Mustang's. However, the designers of the B-24 only knew that their airfoil had very low drag in the wind tunnel. They did not realize that it was a laminar flow airfoil.

Also the Tempest was supposed to have laminar flow wings to overcome problems of the Typhoons thick wings.


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## tomo pauk (Sep 9, 2016)

Not just that Tempest have had a more modern wing profile, the wing itself was much thinner in and of somewhat greater area. A real improvement over the Typhoon's wings.


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## Zipper730 (Sep 10, 2016)

pbehn said:


> from the above link (which surprised me)
> The Consolidated B-24 Liberator "Davis" airfoil was also a laminar flow airfoil, which predates the Mustang's. However, the designers of the B-24 only knew that their airfoil had very low drag in the wind tunnel. They did not realize that it was a laminar flow airfoil.


Did David R. Davis realize that this low drag extended to high speed?


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## Shortround6 (Sep 11, 2016)

I could be wrong but in the case of the Davis airfoil it didn't. 




I would note that the extent of the laminar flow rarely (if ever) reached the figures shown in actual service aircraft. 
Some older airfoils


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## pbehn (Sep 11, 2016)

SR the laminar flow discussion seems to be more like an abstract philosophical debate at time.

"A favorable pressure gradient is required to maintain laminar flow. Laminar flow airfoils are designed to have long favorable pressure gradients. All airfoils must have adverse pressure gradients on their aft end. The usual definition of a laminar flow airfoil is that the favorable pressure gradient ends somewhere between 30% and 75% of chord."

To my mind something that has only 30% of something is way short but that is what is said. Certainly 30% is better than nothing, the Davis profile as lower drag than others. it may or may not have 100% laminar flow but none did.


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## Zipper730 (Sep 11, 2016)

Just to be clear a pressure gradient means the range of pressure along the foil? As for adverse pressure gradients, you mean something that produces a "suction" to basically hold the airflow onto the surface?


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## KiwiBiggles (Sep 11, 2016)

The "pressure gradient" refers to the change of pressure along the chord or the aerofoil. Intuitively, fluids flow readily from a higher pressure to a lower pressure. On the leading part of the aerofoil, the pressure is dropping along the chord, from ambient (or thereabouts) at the leading edge until the lowest pressure is reached; within this section of the chord we say that there is a favourable pressure gradient, and the flow stays largely attached to the surface. From the point of lowest pressure on, the pressure is increasing to once again reach ambient at the trailing edge; in this section the flow is 'fighting against' the unfavourable pressure gradient, and so has a tendency to detach from the surface and become turbulent.

The design of early laminar flow aerofoils pushed the point of maximum thickness rearwards, to try to delay the onset of turbulence. Of course by moving the point of lower pressure further aft, the adverse pressure gradient becomes much steeper and more likely to become turbulent, so there is a delicate balance between keeping attached non-turbulent flow over as much as the chord as possible, and causing too much turbulence and detached flow towards the trailing edge.

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## spicmart (Aug 26, 2019)

I would say the Yak-3 wing looks quite laminar-flow-profile-like.
What do you think?


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## pbehn (Aug 26, 2019)

spicmart said:


> View attachment 550163
> 
> View attachment 550165
> 
> ...


If it was as easy as just how a profile looks then huge resources wouldn't have been spent on wind tunnels. A Spitfires wing looks very aerodynamic and is thinner than a P-51s so to a layman like me it would seem to be lower drag. The physics of laminar flow are complicated and in some ways counter intuitive, "laminar flow" wings were in any case just slightly better not actually true laminar flow and achieving better laminar low did compromise other areas of performance slightly.


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## Wurger (Aug 27, 2019)

Yak-3 like other flighters of the Yak series had the Clark YH ( modified Clark Y ) airfoil for the wing used. The max thickess for the profile is at 30% chord. So it is not the laminar airfoil because such ones have the max thickness at 35-70% chord. For sure the Polish bomber PZL 37 Łoś had the laminar airfoil IAW-743.

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## drgondog (Aug 27, 2019)

Without going too deep in the weeds, NAA crafted the 45-100 airfoil based on the planned/design pressure distribution to achieve Low Drag while still achieving:
1.) CL, CD and CMac values
2.) Stall characteristics
3.) Minimum CDo for a broad range of angle of attack 'alpha'
4.) Wing Thickness T/C 'large enough' to maintain Low Frag but also reduce structural weight of primary spars.

Beginning with a pressure distribution close to the NACA 125 Laminar Flow Airfoil, the Horkey team cranked Friden Calculators for two weeks to perform complex space conformal mapping - combining Laplace, Theodorsen and Kutta-Joukowski methods. The first cut on the Pressure distribution was one that would generate desired Lift, Drag and Moment characteristics (without knowing yet what the airfoil shape must be) as described by Millikan’s principles of selecting a wing, then map the associated surface velocities to achieve the pressure distribution about a rotating cylinder in a Complex Space. The conformal mapping process begins by distributing the velocity data along a rotating Circle in Complex Space, then by transformation, map the circle to an airfoil shape with similar but not yet final desired velocity distribution in Real Space.

The primary goal for a ‘Laminar’ flow airfoil/wing was to develop a smooth aerodynamic shape and surface which enabled more attached flow before boundary layer separation (BL separation is the trigger to cause a ‘profile increase' to the free stream, which causes increasing pressure drag losses). This was achieved to a greater degree in wind tunnel tests of the NACA-125 Laminar Flow airfoil. The NACA-125 airfoil was too thick for High Speed application. It was unique in that it gradually achieved maximum thickness at approximately 50% of chord length instead of the conventional ~25%. Another objective for laminar flow airfoils was to extend the region of peak pressure distribution across a greater percentage of the airfoil chord, to regions past the maximum thickness of the airfoil. Accompanying such shape, for same thickness to chord ratio, is a lower velocity gradient (rate of change of airflow velocity) from airfoil nose to point of maximum thickness, than the corresponding conventional airfoil which had a maximum thickness closer to 25% of the chord. The shape of the wing was also more wedge like than conventional bulbous shape.

FWIIW, the NAA/NACA 45-100 airfoil max T/C was 16.1% at the root and at ~ 37.5 % of the Chord.[edit] The later XP-51F/G/J and H with NACA 65 and 66 series airfoils were close to 60%.

Horkey stated that there was in fact a small but definable laminar flow on the 45-100 but the primary purpose was Low Drag, which it achieved better than any US fighter. (I hesitate to state 'all' including other nations) save the series 66 on the P-63. Like the series 66 on the P-51H, both had slightly lower drag than 45-100 but the 66.2x-116 airfoil on the P-63 was a beast for low speed/stall range.

The Primary aerodynamic value for the NAA/NACA 45-100 was that the lower velocity gradient combined with the 'sharper' LE combined to delay both BL growth and Mach transition to a region further aft along the chord. Took 'longer' to reach critical mach, and when the shockwave originated further aft - the effect on the pitching moment was lower than say the P-38 or P-47 (or Bf 109 and Fw 190). The BL build up as a function of chord position was also lower - hence another reason for low drag.

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## Peter Gunn (Aug 27, 2019)

drgondog said:


> Without going too deep in the weeds, NAA crafted the 45-100 airfoil based on the planned/design pressure distribution to achieve Low Drag while still achieving:
> 1.) CL, CD and CMac values
> 2.) Stall characteristics
> 3.) Minimum CDo for a broad range of angle of attack 'alpha'
> ...


I read this three (3) times... now my head hurts.

I did glean two (2) things from this, well, three (3) actually:

1. Mustang -> FAST
2. Bill -> SMART
3. Me -> Feel like knuckle dragger...

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## spicmart (Aug 27, 2019)

Spontaneously I would say the Yakovlev's wings are less draggy than those of Me 109 and Fw 190....


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## Simon Thomas (Aug 27, 2019)

drgondog said:


> FWIIW, the NAA/NACA 45-100 airfoil max T/C was ~ 37.5 %. The later XP-51F/G/J and H with NACA 65 and 66 series airfoils were close to 60%.


I take it you meant that the location of the max T/C was at those points. An airfoil with a T/C of 60% would be rather thick.

Edit: Some great information in your post. Do you know the dates of when they started & finished design work on the airfoil?

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## AlfaKiloSierra (Aug 27, 2019)

In fact, the term "laminar flow" wing is misleading, as the surface is not smooth enough to prevent turbulent flow. There was a Royal Air Establishment study that used a P-63 with polished filler paint, and that specific airplane attained laminar flow on the wing up to 60% of the chord behind the leading edge; however, the measured waviness of the surface was found to be less than 0.005 inches, unattainable in the field.


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## Niceoldguy58 (Aug 27, 2019)

The B-32 also used the so-called "Davis Wing". I'm not sure about the B-36, but it may have as well. 

I'm not entirely sure about the B-29, but I believe the Boeing wing used on that beast probably had laminar characteristics, too

AlanG


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## pbehn (Aug 27, 2019)

spicmart said:


> View attachment 550255
> 
> View attachment 550256
> 
> ...


Black crosses were known to disrupt airflow.

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## drgondog (Aug 27, 2019)

Simon Thomas said:


> I take it you meant that the location of the max T/C was at those points. An airfoil with a T/C of 60% would be rather thick.
> 
> Correct - I edited it for clarity. The max T/C was 16.5% at Root chord and at location 37.5% of chord.
> 
> Edit: Some great information in your post. Do you know the dates of when they started & finished design work on the airfoil?



The Intensive analytical work of the 10 person/fourteen day design work began immediately after the LOI was signed with Sir Henry Self. In parallel airframe design for the wing started with NACA 23016 airfoil 'just in case' the Low Drag wing airfoil was unsuccessful. Very little, if any re-work was required, following successful wind tunnel results at GALCIT - report submitted in July 1940. By the end of July all of Schmued's preliminary designs were in the hands of the Experimental shop. That said, the empennage and most of the fuselage had already been fabricated, awaiting the wing and powerplant designs.

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## drgondog (Aug 28, 2019)

AlfaKiloSierra said:


> In fact, the term "laminar flow" wing is misleading, as the surface is not smooth enough to prevent turbulent flow. There was a Royal Air Establishment study that used a P-63 with polished filler paint, and that specific airplane attained laminar flow on the wing up to 60% of the chord behind the leading edge; however, the measured waviness of the surface was found to be less than 0.005 inches, unattainable in the field.


 During the full scale wind tunnel tests at NACA Langley, the P-63 in full sealed condition had a CDo of .0171 compared to P-51B value of .0173 (strictly due to the P-63 wing when compared to P-39) but when both restored to 'as delivered' condition the P-63 had a CDo of .0221 vs .0201 for the P-51B. The test velocity conditions were at 100mph, or RN of approximately 1.84x10^6. Th production methods and surface preparation were superior with respect to 'standard' aircraft delivered.

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## Conslaw (Aug 28, 2019)

Despite the P-63 having a much cleaner wing, in the 1946 Cleveland Air Races, Tex Johnson won the piston-powered division in a heavily-modified P-39Q. (Tony LaVier was 2nd in a P-38, by the way.) The other planes were an FG1D, and several P-51s and P-63s. An article on the race can be found here.


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## Zipper730 (Aug 28, 2019)

Was the P-53 or P-60 designed to use laminar-flow wings?


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## wuzak (Aug 30, 2019)

Zipper730 said:


> Was the P-53 or P-60 designed to use laminar-flow wings?



Yes.


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## Zipper730 (Sep 2, 2019)

wuzak said:


> Yes.


Oh that's pretty cool. I didn't know that. That said, I doubt they were anywhere near as good as the P-51 Mustang.

The detail-design on that was (despite being completely straight) fabulous!


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## gumbyk (Sep 2, 2019)

spicmart said:


> Spontaneously I would say the Yakovlev's wings are less draggy than those of Me 109 and Fw 190....


Well, they're smaller than the FW-190 and the 109.
The yak has a fairly clean wing, but its not a laminar flow (supercritical) airfoil.


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## thunderbird (Sep 3, 2019)

As several people have mentioned, no production aircraft achieved laminar flow for any significant benefit. The P-51 achieved a low parasite drag number, by paying close attention to manufacturing processes, primarily bumps, better skin joints to reduce gaps and forward facing steps, and better detail design to eliminate unnecessary roughness and protruberances.

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## Zipper730 (Sep 4, 2019)

thunderbird said:


> As several people have mentioned, no production aircraft achieved laminar flow for any significant benefit. The P-51 achieved a low parasite drag number, by paying close attention to manufacturing processes, primarily bumps, better skin joints to reduce gaps and forward facing steps, and better detail design to eliminate unnecessary roughness and protruberances.


That said, I doubt the P-60 measured up


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## tomo pauk (Sep 5, 2019)

thunderbird said:


> As several people have mentioned, no production aircraft achieved laminar flow for any significant benefit. The P-51 achieved a low parasite drag number, by paying close attention to manufacturing processes, primarily bumps, better skin joints to reduce gaps and forward facing steps, and better detail design to eliminate unnecessary roughness and protruberances.



As measured by Germans, wing section of P-51 was much less draggy than of either Bf 109 or Fw 190. Add the excellent raditor set-up for a tiny cooling drag and there is a big advantage for the P-51.

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## spicmart (Jul 5, 2022)

tomo pauk

Hello.
You once wrote that the airfoil of the Me 109 / Ki-61 had been obsolete and quite draggy. Could you tell where you have read that?


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## drgondog (Jul 5, 2022)

spicmart said:


> tomo pauk
> 
> Hello.
> You once wrote that the airfoil of the Me 109 / Ki-61 had been obsolete and quite draggy. Could you tell where you have read that?


Dr Hoerner devotes an entire chapter analyzing the Bf 109. Chapter 14 "Fluid Dynamic Drag" - see pg 14-9 for tables of comparisons between Bf 109 and P-51 in which both CDt and CDw are ~ 2x over the Mustang.. 

Notably the 109 wing had smaller Thickness Ratio (14.2% Max T/C at root, 11.3% at tip vs P-51 w/16 % Max T/C Root and 12% for Mustang tip). All factors equal, it should have had less profile drag than the Mustang based on 'thinner wing' in velocity range below significant compressibility. RAF and LW concluded the same thing and were mystefied regarding the extreme lower drag values of the P-51. 

We know that several factors were involved to reduce Total Drag of P-51 vs other period fighters. Such As - The fuselage design of employing 2nd order conics, imbedding rdiator/oil cooler into lower fuselage with intake aft of the wing lifting line, optimizing 'scoop/gutter' to peel BL effect at intake entry, 'interior plenum design forward of radiator/intercooler to improve the more gradual reduction of flow to the radiators which achieved lesser boundary layer separation and more equal pressure distribution on front face, the variable exit door controlled by coolant temps achieving a degree of Meredith 'effect' to reduce cooling drag. 

Last but most definitely not least was the superior low drag/high speed airfoil and outstanding surface quality management of the wing.

Back to the 109.

Perusing through the 109 analysis I did not find a correlative CDparasite vs RN for the wing only, but did find CDwing was 37.5% of total CD of the entire airplane,

He states that for total wing CD for the 109 - incl. profile and friction and surface imperfections - equaled 37.5 % of the total CD. 

The Total CD includes the wing CD, the iterference drag, the CD for fuselage, empennage, cockpit, radiator (incl pressure drag), carb intake plus the induced drag.

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## tomo pauk (Jul 5, 2022)

spicmart said:


> tomo pauk
> 
> Hello.
> You once wrote that the airfoil of the Me 109 / Ki-61 had been obsolete and quite draggy. Could you tell where you have read that?



Germans tested the airfoils from Bf 109, Fw 190, P-51 (and a few more), and found that wings' profile drag coefficients were 0.0101, 0.0089 and 0.0072, respectively. That is despite the wing of the Bf 109 being with the lowest t-t-c ratio.
(reference pg. 338 from book 'Vee's for victory')
Ki-61 is worse off, since it had the same profile as the Bf 109, but of greater t-t-c - 16%, ie. same as P-51. Wing area on the Ki-61 was also greater, making the wing-related drag greater still.

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## drgondog (Jul 5, 2022)

tomo pauk said:


> Germans tested the airfoils from Bf 109, Fw 190, P-51 (and a few more), and found that wings' profile drag coefficients were 0.0101, 0.0089 and 0.0072, respectively. That is despite the wing of the Bf 109 being with the lowest t-t-c ratio.
> (reference pg. 338 from book 'Vee's for victory')
> Ki-61 is worse off, since it had the same profile as the Bf 109, but of greater t-t-c - 16%, ie. same as P-51. Wing area on the Ki-61 was also greater, making the wing-related drag greater still.


Hi Tomo - check the source for 0.0089 value for P-51 wing profile drag. 

The NACA Langley full scale tests on P-51B-1 43-12095 at RN=6.19x 10^6 was 0.0070. At RN=1.84x10^6 for 1/4 scale wind tunnel model it was 0.00760.


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## tomo pauk (Jul 5, 2022)

drgondog said:


> Hi Tomo - check the source for 0.0089 value for P-51 wing profile drag.





tomo pauk said:


> Germans tested the airfoils from _Bf 109_,* Fw 190*, *P-51* (and a few more), and found that wings' profile drag coefficients were_ 0.0101_,* 0.0089* and *0.0072*, respectively.

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## spicmart (Jul 5, 2022)

tomo pauk said:


> Germans tested the airfoils from Bf 109, Fw 190, P-51 (and a few more), and found that wings' profile drag coefficients were 0.0101, 0.0089 and 0.0072, respectively. That is despite the wing of the Bf 109 being with the lowest t-t-c ratio.
> (reference pg. 338 from book 'Vee's for victory')
> Ki-61 is worse off, since it had the same profile as the Bf 109, but of greater t-t-c - 16%, ie. same as P-51. Wing area on the Ki-61 was also greater, making the wing-related drag greater still.



Thanks. but what does t-t-c ratio mean? 

Naive assessment: it does not depend on the bluntness of the leading edge. The 190's was more blunt than the 109's.


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## tomo pauk (Jul 5, 2022)

spicmart said:


> Thanks. but what does t-t-c ratio mean?



Thickness-to-chord ratio, usually expressed in percents.



spicmart said:


> Naive assessment: it does not depend on the bluntness of the leading edge. The 190's was more blunt than the 109's



Bluntness is above my pay grade.

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## drgondog (Jul 6, 2022)

tomo pauk said:


>


Be nice ifmy brain worked every day instead of even numbered days


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## tomo pauk (Jul 6, 2022)

drgondog said:


> Be nice ifmy brain worked every day instead of even numbered days



A lot of us would've kill, in order to have that kind of brain...

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## drgondog (Jul 6, 2022)

tomo pauk said:


> A lot of us would've kill, in order to have that kind of brain...


Not the one on 'odd' days.. 'That one' lands you in hospice.

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## Pandorum (Nov 21, 2022)

An interesting article HoHun shared at Flugzeugforum:









Laminar- vs. Turbulent-Flow Airfoils - KITPLANES


Airfoils break down into two general classes based on the behavior of the boundary layer.




www.kitplanes.com





He names the disadvantages of a laminar airfoil at turbulent flow:
- More drag than a conventional profile better suited for the same purpose.
- less maximum lift than a conventional profile

Disadvantages of laminar airfoils at even largely non-turbulent airflow_
- tendentially less maximum lift than conventional airfoils


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## tomo pauk (Nov 21, 2022)

Pandorum said:


> He names the disadvantages of a laminar airfoil at turbulent flow:
> - More drag than a conventional profile better suited for the same purpose.



NAA, NACA and even Germans back in ww2 disagree, if the purpose is to go fast.



Pandorum said:


> - less maximum lift than a conventional profile



Horses for courses.
A ww2 transport aircraft will do just fine with the ancient Clark Y profile, something required to do 400-450-500 mph will need any drag reduction it can have, the wing profile chosen being high on the priority list.


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## pbehn (Nov 21, 2022)

Pandorum said:


> An interesting article HoHun shared at Flugzeugforum:
> 
> 
> 
> ...


The P-51 (Mustang Mk I) had lift to spare for level flight . NAA proposed to the RAF reducing the wing span to make it faster, a genuine 400 MPH. Happily for its future the RAF declined because it would affect climb and take off.


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## Pandorum (Nov 21, 2022)

It has been mentioned that wooden surfaces are smoother than metal ones. So wooden high performance planes like the Mosquito, Hornet and some Russian fighters might have a drag advantage regarding laminar flow. Taking construction under account their weight penalty would be less compared to metal airframes of the same designs as one has to make the wing more rigid in order to get the as good a non-turbulent flow as possible.

I mean with that that if you built a Hornet in metal configuration it would be, say, about 15 % less heavy than the actual one. But as it has a laminar flow airfoil this metal version must have heavier built wings due to tighter tolerances required than if this were not the case. Then it would be only, say, 10 % lighter.
Is this assumption okay?


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## Simon Thomas (Nov 21, 2022)

Tighter tolerances does not necessarily mean a heavier wing.

North American did an excellent job of fit and finish on the P-51. If Brewster had a contract to build P-51's, you can bet they would have significantly higher drag for around the same weight.


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## FLYBOYJ (Nov 21, 2022)

Simon Thomas said:


> Tighter tolerances does not necessarily mean a heavier wing.
> 
> North American did an excellent job of fit and finish on the P-51. If Brewster had a contract to build P-51's, you can bet they would have significantly higher drag for around the same weight.


The "Fit and Finish" requirement would have been the same across the board and IF a subcontractor (like Brewster) "would have" built P-51s under license, they "would have" had to comply with the same requirements put out by NAA or they would not have been accepted by the AAF, let alone their own internal inspectors!

Aircraft are mainly built in assembly jigs, unless you have poor structural assemblers, namely riveters, you're looking at a "cookie cutter" process. You get what the assembly jig gives you.


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## Simon Thomas (Nov 21, 2022)

Brewster would have been given the required specs for building the Corsair, however they were so badly built that none of them saw front line service.


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## FLYBOYJ (Nov 21, 2022)

Simon Thomas said:


> Brewster would have been given the required specs for building the Corsair, however they were so badly built that none of them saw front line service.


That's right, because the company was a train wreck and the government actually took over the place! All segments of manufacturing discipline fell apart.

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## spicmart (Nov 22, 2022)

Simon Thomas said:


> Tighter tolerances does not necessarily mean a heavier wing.
> 
> North American did an excellent job of fit and finish on the P-51. If Brewster had a contract to build P-51's, you can bet they would have significantly higher drag for around the same weight.Ich



The author of above article about laminar vs turbulent airflow article is knowledgeable in the industrie. I guess he knows about tolerances and weight...


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## Simon Thomas (Nov 22, 2022)

I heard him talk at Oshkosh a few years back. He knows his stuff, except when he fell for the Stirling wingspan hangar limitation myth.
Stressed skin wings on combat aeroplanes would rarely need additional thickness to maintain the shape tolerance. 
Barnaby's article was aimed at homebuilts, which usually are not stressed metal skin.


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