Mmmm... I know many warbirds type from which you can't find a consensual flight test datas analyses...

... or better... correct the data so to fit the model, like in GW models for examples... then for sure, datas aren't a problem any more... ;)

I totally disagree with you
The hardest part is to compare, analyse the data and to select the right set... or to create a trustable set from different ones.... there are no "simple ways". Data selection fuels among the hardest disputes between scientists.
Adjusting the model to fit the choosen data set is the easiest part... as John von Neumann said: "With four parameters I can fit an elephant and with five I can make him wiggle his trunk".

Pre-release flight model whingeing.

Yes, we can.

I would think that the most accurate data would be from the manufacturer/and military test flight's, prior to the placing of large goverment orders for the aircraft in question. That data is available for some of the aircraft, if not all of them...it would take alot of leg work, and years of your life to examine:-P

Actually these kind of data concern prototypes, or non-fully equiped aircrafts, that were often particulary well built and adjusted, with carefull and well done covering to get the best performances.

Data from production aircraft are IMHO more representative of combat aircraft.
Data for production aircraft can be retrieved from in-flight receipt test reports (when they were conducted, and when the test centers archives are available....). Normally in each production serie, some machines were intensivelly tested by the respective air forces in order to accept the production serie.
... but... even in these tests, you can find discrepancies in data recorded in test receipts for the same serie.

... I totally agree with your last sentence.

Such kind of data is readily available for the planes of the major combatants, excluding Japan. Japanese destroyed their data at the war's end and available test data is mostly from american sources.
For the Russian planes, the source competent for the state trials and directing the plane construction there, TsAGI, has published an excellent book 'Plane construction in the Soviet Union 1917-1945' (Samolotostroennie in SSSR, 1917-1945) which gives very detailed test data on all soviet planes of the era. If you can read a bit of russian, you ll find the book in the net.
7 years ago, at the time of this game's beginnings, you could find only a smal part of the data treasure that can be found in the net today.. You had to have access to books like this one. Now , everyone can read this Bible, thanks not to Guthenberg, but to the net :))

The kind of data you can find on the western types is such, that you certainly don't need to sift trough. Once you find such sources :

http://www.wwiiaircraftperformance.org/

...you can spare yourself reading the rest.

Lifetime:)? it takes minutes to find out a parameter of a plane. :))))

This is certainly a meaningful remark- prototype test perfomances tend to be higher then the production plane ones. But there is enough test data made on the production planes, too.
In any case, these differences are rather small. For my taste, speed differences of up to 10 km/h ( mind you, the game speeds are mostly accurate), or climb speed differences of 1 m/s would not make me bat an eyelid, nothing to say about writing a post.:)
Any task done in a too perfectionistic manner can last a lifetime:)

And what opinion did I convey... I have mearly made an observation...

Observation.. opinion...

'...Data from who knows where ..' is what I answered.

Yes in theory it would be nice to have more accurate performance modelled... But one thing you have to keep in mind is that not too may people are going to fly those low performers like the I16 against the Emils & Fredericks! I would be kind of a waste of time making those a/c's flyable if nobody is going to fly them. Everybody screams in dogfight servers if the planeset isn't balanced or they leave! You probably would'nt survive very long in an offline Barbarossa campaign flying for the VVS!

Just my thoughts ~S~

Thank's guys, very interesting!...I certainly would love to have accurate handling/performance model for each aircraft...for me, that includes the aircraft on the ground behavior. Maybe Oleg is already planning this for us:)