The Fw190A-8 could only manage 375mph at 26800' and 365mph at 27700'. The Spitfire VIII JF275 with a Merlin 61 was 22mph and 37mph faster and that is with a tropical filter fitted.
That is true. No one is claiming the 190A was a great High Altitude performer. Nor are they claiming it could doing anything more than what is documented. Only in 1942 did the 190 have a commanding advantage over the Spit Mk V. The Mk IX series and the 190A stayed as equals.
http://www.terra.es/personal2/matias.s/fw190.htm190's fought spits in the vertical because they couldn't turn with them. Spits fought 190's in the Horizontal because they could not hang with them in the vertical. The first model of Spitfire that could was the Spitfire Mk XIV. It increased the spit airframe both in power AND weight.
Taken plane for plane the Spitfire IS a more aerodynamic design. This is evident from the following:
http://www.anycities.com/user/j22/j22/aero.htmBut when you factor in the physical size difference, the 190 comes out ahead simply because it has less surface area total. Even it's radial engine drag approximates the surface area of the Spits radiator openings. I instead of two square openings under the wing, you have one circle opening in the front.
The difference IS only POINT TWO (.2). However drag quadruples with velocity. Example, 1 mile and hour = .8 difference, 2 miles and hour = 1.6 difference, 3 miles per hour = 3.2 difference. You can see how quickly that small difference builds up.
Induced drag, no matter how small, adds to the Spits overall drag.
Now some people will claim they can pick up a calculator and figure out the lift Co-efficient for these Airfoils. I myself have to rely on Foilsim or other programs that do a pretty poor job of simulating the atmosphere. Best we got without access to a wind tunnel.
http://www.grc.nasa.gov/WWW/K-12/airplane/liftco.htmlIn regards to the Spitfire Speed. We have a test done at a Merlin 66 (+25). The speed increase in it IS an AVERAGE of 30 mph. It makes some gains.
http://www.fourthfightergroup.com/eagles/merlin66_18_25.jpgHowever at it's full throttle height, It overall speed gain is not very spectacular over the Merlin 61.
Merlin 61 top speed at Full throttle height:
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Maximum true air speed in F.S. supercharger 403 m.p.h. at
27,400 ft.
http://www.fourthfightergroup.com/eagles/bf274.html------------------------------------------------------------------------------------
Merlin 66 (+25)
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Maximum true air speed in F.S. gear = 389 mph at 13,800 feet
http://www.fourthfightergroup.com/eagles/jl165.html------------------------------------------------------------------------------------
Adding a new fuel pump increased it's Full Throttle height speed.
However it is very misleading to quote "30 mph gain". Since no data exists on this website on Merlin (+18) performance without the new pump NOR is there any data for a Merlin (+25) with the new pump the reader is left to speculate.
Judging from comparing speeds approximating (+18) on Table IV and altitudes:
http://www.fourthfightergroup.com/eagles/jl165.htmlAnd comparing them with Table I here:
http://www.fourthfightergroup.com/eagles/ma648.htmlI don't think the Spitfire gained all that much speed from this fuel pump. Around 15 mph at some speeds, ranging down to none at others. Again, it is only speculation since no hard data exists. You certainly cannot claim a 30 mph increase over all, at least not at low altitudes. Remember the Merlin 61 has faster top speed than the Merlin 66 (+25).
The Merlin powered spits just didn't have enough inertia or Horsepower gain to overcome the drag of that same high lift wing which gave them such excellent low speed performance.
Looking at the Speeds I have to conclude the Merlin 66 (+25) is the correct Spit IX to fight the FW-190A8. The contest would be close.
Crumpp