Spit/109 sea level speed comparisons in 1.08 beta patch

[Crumpp]

"of course too fast"

They don't turn too fast. The performance aligns perfectly with a standard turn performance chart.

[JtD]

I'd like to know what data you used, a request couldn't be more straightforward and simple. I didn't ask for adverts, standard turn performance charts or other rubbish.

[Crumpp]

other rubbish

Hold on a second. You attacked the effort and claimed it did not conform to physics.

When I explain it is all standard formulation commonly found in aerodynamic text using the BGS system and present a General Turn Performance table the results agree with perfectly, you claim it is all rubbish.

So what is not "rubbish" to you??

Before I present you with the data, should we agree on what we are looking at???

[Glider]

I admit that my problem is a simple basic one. I believe a huge amount of time and effort is going into trying to hide one clear and obvious truth. That all the pilots and all the test pilots of all the test establishments, in all the nations that compared the 109 and the Spitfire, all agreed that the SPit turned better than the 109.

None of the above mentioned said that there was any difference when in a turning climb and the RAE clearly documented the advantage to the Spitfire. No advice was given to German pilots to go into a climbing turn to escape attack and as far as I am aware, no pilot of the time has said that they used this tactic in combat.

I frankly don't care what a theoretical calculation shows when compared to the tests that were done at the time. Why, because anything done today is just that, a theory unable to be tested in real life, a pricless advantage which occurred in the war years.

Its also worth remembering that the calculations being done today are being done without that 12lb thrust which increased performance of the engine by approx 30%

I invite those who believe that the 109 had the advantage to find any test from any establishment of any nation to support their view.
It shouldn't be difficult if the results are so clear and obvious mathmatically.

[Crumpp]

all agreed that the SPit turned better than the 109.

It does turn better. Look at the calculations I posted.

It just does not do it under all conditions or speeds. That is important, Glider.

If the two airplanes were to have a turning battle to the stall point, the Bf-109E-3 would loose.

Here is the acceleration rates of the two aircraft. The Bf-109E-3 out accelerates the Spitfire Mk I due to its being lighter with more excess thrust.




Of course, the Spitfire can fly at a slower speed were the Bf-109E3 cannot fly at all.

If the Bf-109E3 maintains his trim speed of 400 kph, he is tough customer for a Spitfire to deal with. At that speed, the Bf-109 can sustain better performance and accelerates better. The Spitfire needs to take the fight to the low speed realm where it has all the advantages.

[JtD]

Originally Posted by Crumpp

Hold on a second. You attacked the effort and claimed it did not conform to physics.

Man, whatever goes on in your world. I asked you to share your input data. Three times, won't ask a fourth, so forget about it.

[Crumpp]

Typo on the chart axis....

Acceleration is in fps^2

[Crumpp]

I asked you to share your input data

The data has been posted for each evaluation.

I would be glad to share the input data for this one but what would be the point when you are saying the whole effort does not conform to standard physics.

It does conform. Aerodynamics is nothing more than applied physics and all the formulation is straight out of my college text. It is the same stuff we did in the classroom!

If you agree it conforms, I will be glad to continue the discussion and share the data.

I plan on sharing the spreadsheet too.

[5./JG27.Farber]

Crump - you know if you click the "multi off" button it says "mutli on", then when you click "reply" it will contain these quotes and you can make one post?

[NZtyphoon]

Originally Posted by Crumpp

The data is listed in the thread.

Here it is too, right off the spreadsheet:

Spitfire Mk I

Aircraft Data
weight 6050lbs
Power 990bhp
Level speed 247KEAS
Propeller efficiency 0.8
Wing area 242 sqft
wing efficiency 0.85
Dynamic pressure 206.8101695psf
Aspect Ratio 5.6
Mass 187.8881988 ft/s^2

Where did you assume the propeller efficiency was 0.8?
De H 55409 B 0.930

Rotol RA 611 0.924
Rotol RA 621 0.920
Rotol RA 600 0.911
Rotol RA 640 0.940

Take your pick, which propeller did you claim had an efficiency of 0.8?


http://www.spitfireperformance.com/spit2prop-b.jpg