If the spitfire hadn't have appeared something else would have, probably would have almost as good. Perhaps a Hercules engine fighter (eg Fairy and Gloster) perhaps another Merlin engine fighter. Bolton and Paul defiant scaled down for instance.
As far as the Spitfire wing is concerned it was not 'thin'. It was as thick as any other. The Spitfire wing however had a low thickness to chord ratio of about 13% at the roots and 9% at the aileron hinge. This is referred to as the 'fineness' of the wing. This was not achieved by making the wing thin but by increasing its chord thereby also increasing the wing area. Any downside such as reduced aspect ratio were handled by the elliptical wing.
I've poured over the tables and graphs of wing Clmax at the end of "Theory of Wing Sections: Including a Summary of Airfoil Data" and I can tell you that once over about 10% to 12% thickness the Clmax does not improve much. IE a 18% or 20% thick wing does not have a noticeable Clmax advantage over a 13%. The advantage of the thicker wing is primarily one of structure and internal space. The penalty is higher zero lift drag, especially at high speed when shock drag begins. The data was in the NACA 4 digit tables Eastman Jacobs gave Mitchell.
The structure of the Spitfire wing was efficient as well and so that increased wing area didn't add much of a weight penalty. So Mitchell didn't bother with thickness/chord ratios about 13% because they just don't offer a gain in Clmax in my view.
At a time most biplanes or braced monoplanes had 4-5% thick wings (from sub scale wind tunnels that didnt take into account reynolds effects) Hugo Junkers in his quest for unbraced monoplanes decided to try thick wings in a wind tunnel. His words are in Anderson's history of aerodynamics:
1 The thick wing has slightly more zero lift drag coefficient than a thin wing (ie 5%)
2 The thick wing has significantly higher Clmax and better L/D ratios at useable coefficients of lift.
Junkers invention knocked of by his employee Anthony Fokker and ended up with other Germans makers during WW1
As a result, despite German engines struggling to produce as much power and speed as British aircraft which generally had more powerful engines the German fighters often dominated because they had a far superior climb rate despite lower top speed.
Neverthless wings thicker than 13% don't seem to offer much more and they seem to get worse above 20%.
The Spitfire wing was NACA 2213 at the root meaning: 13% thickness/chord ration, point of max thickness was a 20% and the camber (asymmetry) was 2%. So the point of max thickness was well forward. The wing doesn't look much different than NACA 0013.
As far as the Spitfire wing is concerned it was not 'thin'. It was as thick as any other. The Spitfire wing however had a low thickness to chord ratio of about 13% at the roots and 9% at the aileron hinge. This is referred to as the 'fineness' of the wing. This was not achieved by making the wing thin but by increasing its chord thereby also increasing the wing area. Any downside such as reduced aspect ratio were handled by the elliptical wing.
I've poured over the tables and graphs of wing Clmax at the end of "Theory of Wing Sections: Including a Summary of Airfoil Data" and I can tell you that once over about 10% to 12% thickness the Clmax does not improve much. IE a 18% or 20% thick wing does not have a noticeable Clmax advantage over a 13%. The advantage of the thicker wing is primarily one of structure and internal space. The penalty is higher zero lift drag, especially at high speed when shock drag begins. The data was in the NACA 4 digit tables Eastman Jacobs gave Mitchell.
The structure of the Spitfire wing was efficient as well and so that increased wing area didn't add much of a weight penalty. So Mitchell didn't bother with thickness/chord ratios about 13% because they just don't offer a gain in Clmax in my view.
At a time most biplanes or braced monoplanes had 4-5% thick wings (from sub scale wind tunnels that didnt take into account reynolds effects) Hugo Junkers in his quest for unbraced monoplanes decided to try thick wings in a wind tunnel. His words are in Anderson's history of aerodynamics:
1 The thick wing has slightly more zero lift drag coefficient than a thin wing (ie 5%)
2 The thick wing has significantly higher Clmax and better L/D ratios at useable coefficients of lift.
Junkers invention knocked of by his employee Anthony Fokker and ended up with other Germans makers during WW1
As a result, despite German engines struggling to produce as much power and speed as British aircraft which generally had more powerful engines the German fighters often dominated because they had a far superior climb rate despite lower top speed.
Neverthless wings thicker than 13% don't seem to offer much more and they seem to get worse above 20%.
The Spitfire wing was NACA 2213 at the root meaning: 13% thickness/chord ration, point of max thickness was a 20% and the camber (asymmetry) was 2%. So the point of max thickness was well forward. The wing doesn't look much different than NACA 0013.
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