Re: Comparative Tests Spitfire Mk V vs. Me 109 G
 

If you were installing a DB engine in a German "Spitfire", you would not neccessarily design the same radiators and oil coolers. This has to depend upon the heat transfer properties of the engine, and the oils/cooling fluids used. You might get better cooling from the actual Spitfire installation because it had been "overdesigned" for the DB engine. Or vice versa. I still doubt the value of any information received, that could not have been more cheaply obtained on a test bench.

One thing I can recognise from experience is the argument between the airframe and engine manufacturers, as to just how much power really was available, and who was to blame for overall shortcomings in performance. I can understand the desire of DB engineers to try their engine in someone else's aircraft, as a two-fingered gesture to WM. Look, it works here! Of course, it would not be possible to use that reason as an official purpose of the trials.....

Re: Comparative Tests Spitfire Mk V vs. Me 109 G
 

The title of the DB report is "Überprüfung der Betriebsverhältnisse des Motors DB 605 A in Spitfire under besonderer Berücksichtigung der Kuhl- und Flugleistungen." That works out to about "Examination of the operational conditions of the DB 605 A engine in the Spitfire with special consideration of the a/c cooling and performance."

Perhaps you didn't notice but the DB engine was grafted onto the Spitfire with just enought mods to make the two elements work together. So the radiators and oil coolers remained those of the Spitfire. And the combined system worked without problem, with the readings as shown in the four graphs.

Re: Comparative Tests Spitfire Mk V vs. Me 109 G
 

I didn't need to "notice" - if we take "notice" as meaning make any detailed study of the engineering: I noticed that it worked or history would have been telling us something different. "just enough mods to make (them) work" can hide a lot of engineering sins. For example, did both types have the same cooling fluid? What changes were made to allow for differences? That they worked tells us that the Spitfire system provided enough cooling for the DB engine, which omits one possible option. I still think this could have been discovered on a test-bed, or just by calculation.

Re: Comparative Tests Spitfire Mk V vs. Me 109 G
 

Hi George,

Does the report gives perhaps details of the airframes tested or any serial numbers?

TIA!

Re: Comparative Tests Spitfire Mk V vs. Me 109 G
 

It's a different airplane??

Just a guess.

Re: Comparative Tests Spitfire Mk V vs. Me 109 G
 

If you are referring to the 109, Adam, the answer is, nothing.

The report does specify the following for the Spitfire (since you mentioned these matters in an earlier posting) Propeller: 9-12159 A; spinner: 109; cowling: Bf 110, but with 109 supercharger intake; engine: DB 605 A-1, W.Nr. 00701990.

Re: Comparative Tests Spitfire Mk V vs. Me 109 G
 

Thank you George! :)