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#81 gavagai

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Posted 29 January 2012 - 16:06

where'as other thin winged aircraft fly almost as if they have leading edge slats installed.

Have you flown the Dolphin, D.XII or Camel with high fuel?

Yes I have. In that configuration they are not part of the problem however, aircraft such as the Albatross & Pfalz D.III howecer seem too forgiving, they can be flown too easily near the stall IMO.

Gene DeMarco (vintage aviator) specifically says that the D.Va's stall is forgiving and predictable. The highly cambered wing and the tendency of the whole structure to flex do a lot to explain the Albatros' gentle stall.

That said, most here agree that the RoF Albatros D.III is most believable, while the D.Va and D.II are excessively gentle.
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#82 Panthera

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Posted 29 January 2012 - 17:47

Gene DeMarco (vintage aviator) specifically says that the D.Va's stall is forgiving and predictable. The highly cambered wing and the tendency of the whole structure to flex do a lot to explain the Albatros' gentle stall.

I am curious though, was DeMarco refering to a level flight stall or an accelerated one ?

I do not doubt that the D.Va has a reasonably predictable and forgiving stall, in that you are able to fly it close to the edge and if you enter a spin it is a straight forward procedure to recover. However it also depends on what airfoil was used, be it the Goettingen 173, 174 or 176.

That said, most here agree that the RoF Albatros D.III is most believable, while the D.Va and D.II are excessively gentle.

I agree with that.
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#83 J99Hasso

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Posted 29 January 2012 - 19:14

Gavagai,you have also the technical reports IDFlieg. There are a lot of information, to inter alia Line of engines in varying amounts. Detail I have to take a closer look. From Interresse be expected, the loot all engines were also tested, testing procedures and thus German allii with the same engines, it was found that no Allii engine is necessary for the German engines 60 hours of continuous testing. Not even the Spad / Camel Motoren.I assume that the allii engines had only a short life span under full load and presumably were quickly broken, as we had previously thought.
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#84 gavagai

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Posted 29 January 2012 - 19:29

Here is the exact quote:

The Albatros doesn’t appear to have any nasty habits in flight. Stalls with and without power are straight forward without a huge wing drop, they are preceded by plenty of warning and easily corrected.

Hasso, yes, I have them, but I cannot read them! :P
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#85 Panthera

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Posted 30 January 2012 - 07:10

Thank you gavagai, it seems he is talking about a level flight stall, which is understandable, seeing as testing the accelerated stall characteristics of a 100 year old aircraft is risky business.

Anyway I would expect a more violent depature in a turn for the D.Va & Pfalz D.III than we have ingame atm. Not that it wouldn't come with plenty of warning, just that when it finally departs it will do so with a snap - esp. in the case of the Pfalz D.IIIa fighter which I understand could be pulled into a tight snap stall at will, something German pilots used as an effective evasive maneuver in said aircraft.

Anyway I'd expect most of the thin winged aircraft to snap at a varying degree of viciousness during an accelerated stall.
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#86 gavagai

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Posted 30 January 2012 - 12:16

Thank you gavagai, it seems he is talking about a level flight stall, which is understandable, seeing as testing the accelerated stall characteristics of a 100 year old aircraft is risky business.

Or a brand new replica. ;)
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#87 Panthera

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Posted 30 January 2012 - 14:18

Thank you gavagai, it seems he is talking about a level flight stall, which is understandable, seeing as testing the accelerated stall characteristics of a 100 year old aircraft is risky business.

Or a brand new replica. ;)

A near 100 year old design though, and a very valuable piece which is not really something you'd wanna test to the limit I'd wager :) Anyway he seems to be talking about the level flight stall characteristic, anything else would seem odd considering his words :)

Anyhow, if the Albatros actually featured any wash-out in its' wing design then that would help in terms of controllability near stall and lessen the viciousness of the stall itself.
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#88 .SlackBladder.

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Posted 30 January 2012 - 15:14

http://www.airdromea...eorderform.html" onclick="window.open(this.href);return false;">http://www.airdromea...lanes.com/airdr … rform.html buy one build it and test it lol

I know i will. only 2 grand left before i own my own EIII
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#89 RAF74_Winger

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Posted 31 January 2012 - 03:55

Gene DeMarco (vintage aviator) specifically says that the D.Va's stall is forgiving and predictable. The highly cambered wing and the tendency of the whole structure to flex do a lot to explain the Albatros' gentle stall.

That might not be pertinent to the discussion - it's possible that the Vintage Aviator technicians rigged more (or less) washout into the wing than was present on the originals. Just a thought.

W.
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#90 Panthera

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Posted 01 February 2012 - 00:22

Alright, here's what we got so far in terms of solid verifiable data:

Fokker D.VII & VIII airfoil details:
Type: Goettingen 418
Thickness ratio: 12.7%
Camber: 5.1%
CLmax: 1.55
Critical AoA: 12.5 deg

Fokker Dr.1 airfoil details:
Type: Goettingen 298
Thickness ratio: 12.8%
Camber: 4.5%
CLmax: 1.54
Critical AoA: 13.5 deg

Albatros D.Va airfoil details:
Type: Goettingen 174
Thickness ratio: 8.6%
Camber: 5.6%
CLmax: 1.53
Critical AoA: 7.8 deg

Sopwith Pup, Triplane & Dolphin (& Camel?) airfoil details:
Type: Designated Goettingen 100 [SOPWITH] (RAF 14?)
Thickness ratio: 6.6%
Camber: 3.6%
CLmax: 1.1
Critical AoA: 6 deg

SE5a airfoil details:
Type: RAF 15
Thickness ratio: 6.5%
Camber: 2.6%
CLmax: 1.05
Critical AoA: 6.5 deg

All figures are for a R number of 100,000.

Still looking for data on the Eiffel 14 airfoil, and if the Goettingen 100 isn't the RAF 14 then I'm looking for that too.

More to be found here:
http://www.worldofkrauss.com/" onclick="window.open(this.href);return false;">http://www.worldofkrauss.com/
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#91 Panthera

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Posted 01 February 2012 - 10:33

Based on the real world data above we get the following relative wing loadings for the aircraft:


Relative wing loading [Cl corrected] & power loading (PL)

Fokker Dr.1:…………….20.3 kg/sq.m. (PL: 4.88 kg/hp)
Fokker D.VI:…………….21.3 kg/sq.m. (PL: 4.87 kg/hp)
Sopwith Pup:…………….21.4 kg/sq.m. (PL: 6.25 kg/hp)
Albatros D.III:………….24.5 kg/sq.m. (PL: 4.92 kg/hp)
Fokker D.VII:……………28.5 kg/sq.m. (PL: 3.89 kg/hp)
Sopwith Camel:…………..28.7 kg/sq.m. (PL: 5.19 kg/hp)
Albatros D.Va:…………..28.8 kg/sq.m. (PL: 4.68 kg/hp)
Sopwith Triplane:………..29.6 kg/sq.m. (PL: 5.38 kg/hp)
Sopwith Doplhin:…………31.2 kg/sq.m. (PL: 4.20 kg/hp)
Fokker D.VIII:…………..33.8 kg/sq.m. (PL: 4.68 kg/hp)
RAF SE5a:……………….38.0 kg/sq.m. (PL: 4.52 kg/hp)

The above should give a pretty good idea of which fighters prevailed in an angles fight as-well as their climb performance.
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#92 MiG-77

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Posted 01 February 2012 - 11:59

The above should give a pretty good idea of which fighters prevailed in an angles fight as-well as their climb performance.


Not really. Your list dont take account IE wings gap/chord ratio and stagger.
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#93 Finkeren

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Posted 01 February 2012 - 12:04

Albatros D.III:………….24.5 kg/sq.m. (PL: 4.92 kg/hp)

Sopwith Camel:…………..28.7 kg/sq.m. (PL: 5.19 kg/hp)

The above should give a pretty good idea of which fighters prevailed in an angles fight as-well as their climb performance.

I think those two examples alone would discredit that simplistic method of comparison.
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#94 hq_Jorri

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Posted 01 February 2012 - 12:18

Fokker D.VII & VIII airfoil details:
Type: Goettingen 418
Thickness ratio: 12.7%
Camber: 5.1%
CLmax: 1.55
Critical AoA: 12.5 deg

Don't know about all this technical stuff but I do know the D.VII top wing is quite heavily tapered. You can't just apply a single airfoil on it.
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#95 Panthera

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Posted 01 February 2012 - 13:40

Fokker D.VII & VIII airfoil details:
Type: Goettingen 418
Thickness ratio: 12.7%
Camber: 5.1%
CLmax: 1.55
Critical AoA: 12.5 deg

Don't know about all this technical stuff but I do know the D.VII top wing is quite heavily tapered. You can't just apply a single airfoil on it.

Not really heavily tapered, but it has been taken into account, the thickness ratio goes from 13% (Clmax 1.57) at the root to 9.5%(Clmax 1.54) at the tip, which gives an average Clmax of 1.55.
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#96 Tom-Cundall

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Posted 01 February 2012 - 15:03

Albatros D.III:………….24.5 kg/sq.m. (PL: 4.92 kg/hp)

Sopwith Camel:…………..28.7 kg/sq.m. (PL: 5.19 kg/hp)

The above should give a pretty good idea of which fighters prevailed in an angles fight as-well as their climb performance.

I think those two examples alone would discredit that simplistic method of comparison.

I agree.
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#97 Panthera

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Posted 01 February 2012 - 15:09

Albatros D.III:………….24.5 kg/sq.m. (PL: 4.92 kg/hp)

Sopwith Camel:…………..28.7 kg/sq.m. (PL: 5.19 kg/hp)

The above should give a pretty good idea of which fighters prevailed in an angles fight as-well as their climb performance.

I think those two examples alone would discredit that simplistic method of comparison.

How so?

Take into consideration that I used 180 hp as the power rating for the D.III's mercedes engine based on British ratings of the engine.

Also I can't find any evidence to suggest that the Albatros couldn't turn with a Camel, atleast initially, but you're welcome to provide any ofcourse.
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#98 Panthera

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Posted 01 February 2012 - 15:17

The above should give a pretty good idea of which fighters prevailed in an angles fight as-well as their climb performance.


Not really. Your list dont take account IE wings gap/chord ratio and stagger.

While it is true that chord gap & stagger weren't directly taken into account one can simply note that most of the aircraft featured a 1:1 chord gap between the wings, whilst the fighters that use smaller lower wings are at an advantage as they will feature a reduced interference and stagger compared to the fighters with symmetric upper & lower wings.

In short: The end result of taking these factors into consideration would be that we would find the fighters with smaller and slightly offset lower wings gain an extra advantage; which would include aircraft such as the Nieuport 11 & 17, Fokker D.VI, VII & VIII, Albatros D.Va etc.
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#99 MiG-77

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Posted 01 February 2012 - 15:20

While it is true that chord gap & stagger weren't directly taken into account one can simply note that most of the aircraft featured a 1:1 chord gap, whilst the fighters that use smaller lower wings were at an advantage in terms of reducing interference and stagger.

In short: The resulting findings of taking these factors into consideration would be that the fighters with smaller and slight offset lower wings gain an extra advantage.

1:1 ratio is not correct most of the planes. Most have either less or more. Also gap/chord ratio make big difference and monoplanes (IE D.VIII) benefit largely because of this.
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#100 Panthera

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Posted 01 February 2012 - 15:23

While it is true that chord gap & stagger weren't directly taken into account one can simply note that most of the aircraft featured a 1:1 chord gap, whilst the fighters that use smaller lower wings were at an advantage in terms of reducing interference and stagger.

In short: The resulting findings of taking these factors into consideration would be that the fighters with smaller and slight offset lower wings gain an extra advantage.

1:1 ratio is not correct most of the planes. Most have either less or more. Also gap/chord ratio make big difference and monoplanes (IE D.VIII) benefit largely because of this.

It seems like it is for most of the German planes actually, and good load of the British ones too.
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#101 MiG-77

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Posted 01 February 2012 - 15:29

It seems like it is for most of the German planes actually.

D.VII has 1.1, Albatros and Pfalz has more than that, etc, so no. SE5 has less than 1, as has Camel and Pup. Most planes dont have excact ratio of 1:1.
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#102 Panthera

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Posted 01 February 2012 - 15:41

It seems like it is for most of the German planes actually.

D.VII has 1.1, Albatros and Pfalz has more than that, etc, so no. SE5 has less than 1, as has Camel and Pup. Most planes dont have excact ratio of 1:1.

If we're concerned about such small differences, then sure, you're right. The aircraft with the highest gap get an added advantage, whilst those with offset lower wings get an even higher one.

In short, aircraft such as the Fokker D.VI, VII, Albatros D.Va, Neiuport 11 & 17 are at a futher advantage compared to aircraft such as the Camel, SE5a etc etc… Whilst the Fokker DVIII benefits a lot from its tapered monoplane construction.
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#103 MiG-77

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Posted 01 February 2012 - 15:46

If we're concerned about such small differences, then sure, you're right. The aircraft with the highest gap get an added advantage, whilst those with offset lower wings get an even higher one.

Those "small" differences has as much as effect as Clmax and wingarea. They directly affect how effective given wingarea is. Monoplanes that is 100% and everything else less, depending configuration. Triplanes are even more affected by this.

In short, aircraft such as the Fokker D.VI, VII, Albatros D.Va, Neiuport 11 & 17 are at a futher advantage compared to aircraft such as the Camel, SE5a etc etc… Whilst the Fokker DVIII benefits a lot from its tapered monoplane construction.

Yes they have. And it explains why planes like SPAD XIII were considered as "flying brick". (relatively low wingloading, but small gap and not stagger at all). Im just saying that your list is not accurate as it wont take account even this.
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#104 Dr.Zebra

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Posted 01 February 2012 - 15:59

Albatros D.III:………….24.5 kg/sq.m. (PL: 4.92 kg/hp)

Sopwith Camel:…………..28.7 kg/sq.m. (PL: 5.19 kg/hp)

The above should give a pretty good idea of which fighters prevailed in an angles fight as-well as their climb performance.

I think those two examples alone would discredit that simplistic method of comparison.

not really, since "manouverabilty" has several properties. In the case of the Camel, the key aspekt is mass distribution (and precesion + torque effects) which together with the wing profile also lead to the more challenging flightenvelope. A low wingloading is more important in continous turning (and low speed handling) and not necessarily in "changing direction". The camel swings around its tightly centered mass. And we are not even talking control surfaces here, were 4 ailerons mean more induced drag and negative turn momentum but high initial banking change rates…

The albatross on the other hand has quite "modern" wingtips and relative high aspekt ratio, so it must have some benefits in the induced drag area, but drawbacks in maneuverability. While its mass distribution gives gentler, but far less "agressive" maneuverabilty and easier stall behavior.

I think that is more or less consistent with the data above
so we can conclude an albie would probably been able to turn with a camel in sustained turning, but not so much any more once the direction changes start.

Don't know about all this technical stuff but I do know the D.VII top wing is quite heavily tapered. You can't just apply a single airfoil on it.

It is not "tapered" if you refering to the view cut-out. A tapered wing is one with slender tips like on an albatross (the bird even more then the plane)
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#105 Panthera

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Posted 01 February 2012 - 16:06

Those "small" differnces has as much as effect as and Clmax and wingarea. They directly affect how effective given wingarea is. Monoplanes that is 100% and everything else less, depending configuration. Triplanes are even more affected by this.

If the difference is no more than 20%, such as 0.8:1 vs 1:1, then the effect is not that decisive. The size and position of the lower wing + the airfoil CLmax of both wings then means a lot more.

Yes they have. And it explains why planes like SPAD XIII were considered "flying brick". (relatively low wingloading, but small gap and not stagger at all). Im just saying that your list is not accurate as it wont take account even this.

Whilst the lower gap to chord ratio of the SPAD XIII's wings didn't do it any good in terms of efficient lift production, it was nonetheless the choice of airfoil that really let it down in the agility department. The 4.5% thick Eiffel 14 airfoil featured a CLmax of less than 0.95 and a very low critical AoA to boot, all of which makes for very poor agility in the horizontal.
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#106 Tom-Cundall

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Posted 01 February 2012 - 16:09

Mig you're wasting your time I've brought this up before. All Panthera is interested in is CL-max, wing loading and power to weight. He doesn't look at the whole picture in anywhere near enough complexity (or even the historic variables that effected performance) and thinks that he can draw definitive conclusions from the calculations he makes.

NACA reports have some information on the effects, (http://www.aerodesig...anes/nr0151.pdf" onclick="window.open(this.href);return false;">http://www.aerodesig...sc.br/teoria/ar … nr0151.pdf) but basically for a biplane (or triplane) with equal top and bottom wings, equal incidence and one chord gap, the top wing will develop about 1.2 times the Cl of the lower. In general in a multi-wing aircraft the top wing will stall first, which is beneficial since it will make the nose tend to pitch down.

Regardless of position, in a biplane (and triplane) both wings will affect each other (as will all flying surfaces), sometimes significantly. The two primary areas of significance are the pressure distributions and the induced flow. The degree of the interaction is then a function of the design and the relative position of one wing versus the other.

The presense of the top wing affects the pressure distribution of the bottom wing(s) by decreasing the magnitude of the low pressure distribution. The closer the wings are together, the more suppressed this distribution is. Given two wings of equal size and placed directly one on top of the other, and spaced between one and two chords apart, the bottom wing generates only about 70% of the lift of the top wing. So here is where the stagger comes into play.

On a triplane this has a knock on effect as there is a middle wing which both effects the efficiency of the lower wing and is itself a victim of the effect from the top wing. This can create complex vortices and very 'dirty' airflow across the surfaces and up onto tail plane. Have you modelled this?

When the wings are displaced longitudinally, the effect of the upper on the lower is reduced so that they begin to deliver nearly the same performance. There is still the issue of the induced angle of attack but that becomes secondary.

Here you go:

http://www.jefflewis..._monoplane.html" onclick="window.open(this.href);return false;">http://www.jefflewis.../aviation_theor … plane.html

http://www.physicsfo...ad.php?t=127837" onclick="window.open(this.href);return false;">http://www.physicsfo...ad.php?t=127837

It's like trying to work at Cern and doing all your calculations on the back of your sandwich wrapper using only an abacus.
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#107 Panthera

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Posted 01 February 2012 - 16:16

Albatros D.III:………….24.5 kg/sq.m. (PL: 4.92 kg/hp)

Sopwith Camel:…………..28.7 kg/sq.m. (PL: 5.19 kg/hp)

The above should give a pretty good idea of which fighters prevailed in an angles fight as-well as their climb performance.

I think those two examples alone would discredit that simplistic method of comparison.

not really, since "manouverabilty" has several properties. In the case of the Camel, the key aspekt is mass distribution (and precesion + torque effects) which together with the wing profile also lead to the more challenging flightenvelope. A low wingloading is more important in continous turning (and low speed handling) and not necessarily in "changing direction". The camel swings around its tightly centered mass. And we are not even talking control surfaces here, were 4 ailerons mean more induced drag and negative turn momentum but high initial banking change rates…

The albatross on the other hand has quite "modern" wingtips and relative high aspekt ratio, so it must have some benefits in the induced drag area, but drawbacks in maneuverability. While its mass distribution gives gentler, but far less "agressive" maneuverabilty and easier stall behavior.

I think that is more or less consistent with the data above

I agree with this.

It is clear that the Camel should be able to change direction more quickly than the Albatros by virtue of its' extra aileron surface area (four ailerons) and the gyroscopic effect of the rotary engine would also likely enable it to pull off tight barrel rolls that an Albatros wouldn't be able to follow.

In a straight turn & burn fight however, where both pilots simply circle to get into firing position, it seems as though the Albatross had a slight advantage, whilst the reverse was true in an up close knife fight for which the Camel was better suited.
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#108 Panthera

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Posted 01 February 2012 - 16:18

It is not "tapered" if you refering to the view cut-out. A tapered wing is one with slender tips like on an albatross (the bird even more then the plane)

I'm sure he was refering to the tapering thickness of the wing :)
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#109 MiG-77

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Posted 01 February 2012 - 16:20

If the difference is no more than 20%, such as 0.8:1 vs 1:1, then the effect is not that decisive. The size and position of the lower wing + the airfoil CLmax of both wings then means a lot more.

0.75:1 gap/chord ratio has about 75% effectiveness of monoplane in lift. In exactly same configuration 1.25:1 gap/chord has about 87% effectivenes of monoplane and 1.5:1 ratio has about 89%. This makes big difference in planes.


Whilst the lower gap to chord ratio of the SPAD XIII's wings didn't do it any good in terms of efficient lift production, it was nonetheless the choice of airfoil that really let it down in the agility department. The 4.5% thick Eiffel 14 airfoil featured a CLmax of less than 0.95 and a very low critical AoA to boot, all of which makes for very poor agility in the horizontal.

While that is true also so is its low gap/chord ratio. Point is that gap/chord and stagger ratio makes big difference alone as you can compare it to ie SE5a (which was better turning plane of the two).
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#110 Panthera

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Posted 01 February 2012 - 16:31

Mig you're wasting your time I've brought this up before. All Panthera is interested in is CL-max, wing loading and power to weight. He doesn't look at the whole picture in anywhere near enough complexity (or even the historic variables that effected performance) and thinks that he can draw definitive conclusions from the calculations he makes.

NACA reports have some information on the effects, (http://www.aerodesig...anes/nr0151.pdf" onclick="window.open(this.href);return false;">http://www.aerodesig...sc.br/teoria/ar … nr0151.pdf) but basically for a biplane (or triplane) with equal top and bottom wings, equal incidence and one chord gap, the top wing will develop about 1.2 times the Cl of the lower. In general in a multi-wing aircraft the top wing will stall first, which is beneficial since it will make the nose tend to pitch down.

Regardless of position, in a biplane (and triplane) both wings will affect each other (as will all flying surfaces), sometimes significantly. The two primary areas of significance are the pressure distributions and the induced flow. The degree of the interaction is then a function of the design and the relative position of one wing versus the other.

The presense of the top wing affects the pressure distribution of the bottom wing(s) by decreasing the magnitude of the low pressure distribution. The closer the wings are together, the more suppressed this distribution is. Given two wings of equal size and placed directly one on top of the other, and spaced between one and two chords apart, the bottom wing generates only about 70% of the lift of the top wing. So here is where the stagger comes into play.

On a triplane this has a knock on effect as there is a middle wing which both effects the efficiency of the lower wing and is itself a victim of the effect from the top wing. This can create complex vortices and very 'dirty' airflow across the surfaces and up onto tail plane. Have you modelled this?

When the wings are displaced longitudinally, the effect of the upper on the lower is reduced so that they begin to deliver nearly the same performance. There is still the issue of the induced angle of attack but that becomes secondary.

Here you go:

http://www.jefflewis..._monoplane.html" onclick="window.open(this.href);return false;">http://www.jefflewis.../aviation_theor … plane.html

http://www.physicsfo...ad.php?t=127837" onclick="window.open(this.href);return false;">http://www.physicsfo...ad.php?t=127837

It's like trying to work at Cern and doing all your calculations on the back of your sandwich wrapper using only an abacus.

Tom, like I have said many times by now, I have taken it into account.

You seem unable to understand however that this is bad news for your arguments concerning the Sopwith Camel, seeing as it featured not only a smaller wing gap to chord ratio than most of the German planes, but more importantly also symmetric upper & lower wings. - also note the lower wing dihedral.

I mean we can take all of these things into consideration, but it wont change the end result much from what the basic figures show us. Only the Fokker D.VIII will really perform better than what the basic figures indicate by comparison to the rest.
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#111 Panthera

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Posted 01 February 2012 - 16:36

0.75:1 gap/chord ratio has about 75% effectiveness of monoplane in lift. In exactly same configuration 1.25:1 gap/chord has about 87% effectivenes of monoplane and 1.5:1 ratio has about 89%. This makes big difference in planes.

Well if we have such a large difference in gap/chord ratio, 0.75 to 1.25 (or in other words +66%), then ofcourse we will start to see it having a significant effect :D

But IIRC most of the aircraft didn't differ by that much (50+ %) in gap/chord ratio, but ofcourse between those who did then this phenomenon would make a big difference.

While that is true also so is its low gap/chord ratio. Point is that gap/chord and stagger ratio makes big difference alone as you can compare it to ie SE5a (which was better turning plane of the two).

Most certainly, no disagreement there :)
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#112 MiG-77

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Posted 01 February 2012 - 16:47

Well ofcourse if we have such a large difference in gap/chord ratio, 0.75 to 1.25 (or in other words +66%), then we will start to see it having a significant effect :D But most of the aircraft didn't differ by that much in gap/chord ratio.

1:1 ratio had 82% of monoplane lift. So differences are very comparable to how much clmax affect (IE raf14 vs raf15, different Gottingen airfoils, etc).
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#113 Tom-Cundall

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Posted 01 February 2012 - 16:48

You seem unable to understand however that this is bad news for your arguments concerning the Sopwith Camel

What arguments concerning the Camel?

Can you link to where I have posted these arguments?
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#114 MiG-77

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Posted 01 February 2012 - 16:50

You seem unable to understand however that this is bad news for your arguments concerning the Sopwith Camel

What arguments concerning the Camel?

Can you link to where I have posted these arguments?

Also, it is even more bad news to Dr.I ;)
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#115 Panthera

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Posted 01 February 2012 - 16:55

You seem unable to understand however that this is bad news for your arguments concerning the Sopwith Camel

What arguments concerning the Camel?

Can you link to where I have posted these arguments?

Re: unrealistic speed of Camel

Tom Cundall Fri Jan 20, 2012 2:51 pm:
"Both the Clownwagon, Camel and Albs are all wrong in terms of FM and speed but to claim that the Dr.1 is fine while the Camel and Albs are wrong is a bias in the same way as in that other thread you think the D.VII should turn inside a Camel. Superior in other ways certainly - but in terms of turning circle in a straight one on one fight- you are mistaken and as your opinions always come down on one side I think that can be viewed as a bias towards the Fokker aircraft instead of a play towards historical accuracy."
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#116 Panthera

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Posted 01 February 2012 - 16:59

You seem unable to understand however that this is bad news for your arguments concerning the Sopwith Camel

What arguments concerning the Camel?

Can you link to where I have posted these arguments?

Also, it is even more bad news to Dr.I ;)

Well, the Camel and Dr.1 have a similar gap/chord ratio and slight positive stagger, whilst the Dr.1 has the advantage of a thicker high lift airfoil and higher wing aspect ratio.

Now the triplane configuration will no doubt result in a larger reduction in lift production as apposed to a biplane one for any given gap/chord ratio, everything else being equal. However the 50+% difference in Clmax between the airfoils used, and aspect ratio more than makes up for this.
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#117 MiG-77

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Posted 01 February 2012 - 17:04

Well, the Camel and Dr.1 have a similar gap/chord ratio and slight positive stagger, whilst the Dr.1 has the advantage of a thicker high lift airfoil and higher wing aspect ratio.

Now the triplane configuration will no doubt result in a larger reduction in lift production as apposed to a biplane one for any given gap/chord ratio, everything else being equal. However the 50+% difference in Clmax between the airfoils used, and aspect ratio more than makes up for this.

Well, I was referring to your list. While you took account clmax, you didnt take accout that Dr.I is triplane and have less efficiency than any biplane. -> Dr.I and Triplane would took biggest hit in that list ;)
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#118 Panthera

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Posted 01 February 2012 - 17:06

Well ofcourse if we have such a large difference in gap/chord ratio, 0.75 to 1.25 (or in other words +66%), then we will start to see it having a significant effect :D But most of the aircraft didn't differ by that much in gap/chord ratio.

1:1 ratio had 82% of monoplane lift. So differences are very comparable to how much clmax affect (IE raf14 vs raf15, different Gottingen airfoils, etc).

Well that's 18% between a monoplane and a biplane, but the difference between two biplanes, one with a gap/chord ratio of 0.9:1 and the other one with say 1:1.2 will be even less.

And as such we can probably agree that the 50+% difference in wing CLmax between the RAF 14 & Goettingen 418 definitely has a much larger impact :D
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#119 Panthera

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Posted 01 February 2012 - 17:07

Well, the Camel and Dr.1 have a similar gap/chord ratio and slight positive stagger, whilst the Dr.1 has the advantage of a thicker high lift airfoil and higher wing aspect ratio.

Now the triplane configuration will no doubt result in a larger reduction in lift production as apposed to a biplane one for any given gap/chord ratio, everything else being equal. However the 50+% difference in Clmax between the airfoils used, and aspect ratio more than makes up for this.

Well, I was referring to your list. While you took account clmax, you didnt take accout that Dr.I is triplane and have less efficiency than any biplane.-> Dr.I and Triplane would took biggest hit in that list ;)

That is very true, you could probably justify adding an additional 7% to its relative wing loading compared to the rest. As for the Sopwith Triplane probably abit more because of the symmetrical wing setup.
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#120 MiG-77

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Posted 01 February 2012 - 17:11

Well that's 18% between a monoplane and a biplane, but the difference between two biplanes, one with a gap/chord ratio of 0.9:1 and the other one with say 1:1.2 will be even less.

Those would have difference about 5-7% in lift if everything else equal.

Then the 50+% difference in wing CLmax between the RAF 14 & Goettingen 418 definitely has a much larger impact :)

Very similar to PuP and Nieuport 17 gap/chord ratio difference.
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