Well of course, since we have your toy excel sheet against thoroughly documented test data! :D :D

I hve in mind the guns (barrel for sure). I think the rad were different. But I need to check this. There is also a good article on the net (in French probably) if you browse around "bf109" and switzerland ("Suisse"). Will try to have a look.

EDIT:
Guns for sure and prop

Well you guessed wrong! I actually did a post a while back arguing for the introduction of subsonic drag rise which is missing in CloD but modelled in the C++ simulation. Modelled a Spitfire Mk1 and showed that the speed build up in CloD in quicker than it should be because compressibility effects are missing.

Seeing you seem to be such an expert perhaps you would be so kind to point out what is wrong in my Me109E speed/alt chart and how it really should look like?

Yes I will check that, I had a good (IIRC German language) book about Swiss 109s, which helped me to ID J-347's WNr. and service record.

As for the gun barrels, I am not sure - one of the tests being waved about is explicitely about measuring the speed diff. between guns present/not present, and it's about 1 km/h.. I'd imagine different gun barrels amount to even less. ;)

Rads look interesting though, this might account for something, but again, looking the Swiss test results, the difference is only about 8 kph at VDH, which from my experience, is an extremely good match for a serial production plane compared to the guaranteed specs!

Well for one it probably has wrong data.. guessworked drag, guessworked wing effiencies, guessworked propeller effiency, manipulated until it fits one's agenda. :D

As Tagert said, garbage in... garbage out.

BTW, care to tell why you disappeared from allaboutwarafe forums? I am sure it's hell of a story. :D :D :D

The core.. That's not too much to ask.

I think people are aware by your modus operandi by now: If you don't like the message then discredit the messenger.

Me "disappering" is for no more sinister reason than for working on a book project. Believe me it's much more satisfying than arguing about your doctored data or sparring with your mathematically challenged pal Crumpp!

So if my Me109E data is so totally wrong then I guess this means that HoHun's charts are off the wall as well because we get the same results, i.e. around 475 Km/h on the deck. Garbage in and garbage out in both cases huh?

BTW: Concerning disappering, in your case we know the answer don't we? Permanently banned from a number of forums and as editor in Wikipedia. That sure is one hell of a story! :D :D :D

Actually it is. I'm going to use the C++ results in a book project so I'm not going to sink my own project by posting my code before that :)

Nobody needs to discredit you.

.. but you seem to need to discredit others. :D

It is. It doesn't match tested results, does it?

I would love too see those test results.

Seems to me like you are confusing the calculated speed of the V15 prototype at 1.35 ata or the caveted Messerschmitt marketing material with actual test results. The only test results I've seen point to 466-475 Km/h.

You still have not answered the question: How do you account for HoHun's estimate of 475 Km/h?

And that is why we only see the V15 prototype data and not data for production Bf109Es.