[Test Pilot]

Bf 109 F-4 with Db601E, take of weight 2890kg, performance with 1.42 Ata
0km - 537 km/h
6.2km - 670 km/h
initial climb rate ~ 21 m/s
turn time ~ 20 sec

As far as I know the 670km/h topspeed given for the 1.42 ata DB601E is without compressibility correction. Actual topspeed is more in the range of 650km/h!

Bf 109 G-6 (early) with Db605A, take of weight 3100kg, performance with 1.3Ata
0km - 510 km/h
6.6km - 630 km/h
initial climb rate ~ 17 m/s
turn time ~ 22 sec


Bf 109 G-6 (late) with Db605A, take of weight 3100kg, performance with 1.42 Ata
0km - 530 km/h
6.6km - 640 km/h
initial climb rate ~ m/s
turn time ~ 22 sec

Notice how topspeed for the G-2 is given at 7km but for the G-6 at 6.6km? Actual topspeeds for the two G-6s at 7km is 640 and 650km/h respectively when extrapolating to the higher altitude!

22secs for turntime is also rather high. The Soviets have tested a G-4 to turn between 20.5 - 21.0 secs which is just 0.5sec higher than what they got for the G-2 (20.0 - 20.5).
Keeping in mind that the G-6 is just something like 30kg heavier than the G-4 I cant imagine it turning worse by as much as a whole second!

Ad. Bf 109 F-4

Yes i also suspect that these test was without compresibility correction and 650km/h look more reliable. Kurfurst in his site accept 670 km/h even if he accept that other raports was without copresibiity.

Ad. G-2 and G-6

Notice also that other raports ( also in Kurfurs site) claim lower high alt for G-2 also:

"...Appearantly the calculated dataset proved rather accurate - the avarage of the ERLA values obtained on production airframes was 652 km/h (the accepted airfames results ranged from 632 to 664 km/h, the three rejected airframes below the minimum tolerance not included), and three production airframes exceeding the reference specification; however the avarage the rated altitudes measured (ranging 6450m to 6950m) was lower, 6700m, probably as a result of the greater variance in thermal effiency than expected originally.

Trials at E-Stelle Rechlin on a Bf 109G-1 - the results were later becoming the official specifications for the type in a Kennblatt issued on 8 March 1943 - resulted in 650 kph at 6400m; the tested aircraft appearantly had a fixed tailwheel resulting 12 km/h speed loss, which needs to be taken account."

So probalby ( as i think) retractable taiwhell could make such difference also. With it max speed was reached at higher altitudes ( confirm these russian test with G-2 with retractable tailwheel )

G-6 had not retractable tailwheel so the speed and hegith were less then in G-2.

Rember that G-4 was more similar to G-2 then to G-6 beacuse dont have Mg131 and was lighter.

Ad. Turnig times.

Russian test reported:

Bf 109 F-4 ( left - right turn )
19,6 - 20.5 sec

Bf 109 G-2
20- 21,5 sec

So G-6 should be worse but we dont have detalied info.

Probably it coud be:

21-22,5 sec

I suppose 22 sec is quite accurate turnig time for G-6.

See that G-6 had noticable worse performance then G-2 both in speed and climb due to its gross weight and worse aerodynamical shape. We dont know how much worse it was but German pilots reports that G-6 has noticable worse in handling and turns and describe it as a "heavy"

Also here are some info about testing 109 G-2 by Finish pilots:

"Other data: stall speed clean 170 km/h (could not be clearly defined). The nose sunk and the plane banked calmly to the right wing. At landing configuration the stall speed was 145 km/h. With full power the plane could be held hanging from the prop at 60