Er, I must humbly deny being on the list - I'm just a 'look up the internet, think about it a little, and copy and post' guy. I can only comment on what everyone already talked about, and mush up all the info in conclusion. Nothing original out of me, nor do I have any kind of firsthand info.
As for the turn time/radius info from Soviet sources, here's how our AH info compares. I'm not sure how the Soviets tested it.. but the AH2 values are for all planes at under 500ft altitude using WEP settings for throttle and turning as tightly as possible without consideration for turn rate, only turn radius:
Soviet Source
All At 1,000m(3,000ft) altitude
Spitfire IXLF - 235m
Yak 1 - 275m
Yak 9? - 290m
La-5 : 310m
La-5FN : 295m
Me109G-2 : 290m
FW190A : 340m
P-39 : 253-280m
AH2
All at 500ft altitude
Spit Mk.8: 170.7m
Yak1: plane not available
Yak-9T: 205.0m
Yak-9U: 205.5m
La-5: plane not available
La-5FN: 199.8m
Bf109G-2: 214.0m
Fw190A-5: 269.0m
Fw190A-8: 296.3m
P-39: plane not available
All our AH planes has about 30~50m smaller radius than the real life figures universally. No doubt the real life figures were using different test perimeters.