In-game level speed tests

[102nd-YU-devill]

Hi all,

 

I did a little bit of speed testing the other night and wanted to share results here.

I overlaid the results onto the same scale/range/values graph from ww2aircraftperformance website for reference.

My results are dots, i.e. data points of similar color to real life counterparts in the original graph.

 

Test conditions: level autopilot engaged, trim as low drag as possible, radiators auto, x8 speed until speed stabilizes.

Kuban spring map, no wind, quick mission.

Tested then a few samples on Berloga, same results.

 

Bf109G2 data is for 2600RPM, ie. 30min combat settings in IL2 (default loadout)

Spit 9e data is for Merlin 66, 3000RPM +18lbs/sq.in. boost, ie. emergency 5min power (default loadout).

In other words test conditions as close to what is described in the mentioned website tests.

 

I also did tests for 109F4, 109G2, 190A5, P38J, P47D22 and SpitVb at all engine regimes, but since I don't have references I didn't show them here.

If you are interested I will add them to the post.

 

I don't know... comments?

 

Cheers!

 

[BlitzPig_EL]

The G2 has been wildly overperforming for ages.

[CountZero]

49 minutes ago, 102nd-YU-devill said:

Hi all,

 

I did a little bit of speed testing the other night and wanted to share results here.

I overlaid the results onto the same scale/range/values graph from ww2aircraftperformance website for reference.

My results are dots, i.e. data points of similar color to real life counterparts in the original graph.

 

Test conditions: level autopilot engaged, trim as low drag as possible, radiators auto, x8 speed until speed stabilizes.

Kuban spring map, no wind, quick mission.

Tested then a few samples on Berloga, same results.

 

Bf109G2 data is for 2600RPM, ie. 30min combat settings in IL2 (default loadout)

Spit 9e data is for Merlin 66, 3000RPM +18lbs/sq.in. boost, ie. emergency 5min power (default loadout).

In other words test conditions as close to what is described in the mentioned website tests.

 

I also did tests for 109F4, 109G2, 190A5, P38J, P47D22 and SpitVb at all engine regimes, but since I don't have references I didn't show them here.

If you are interested I will add them to the post.

 

I don't know... comments?

 

Cheers!

 

I posted my sped tests here, for most airplanes using old IL-2 compare

 

my 109G2 vs Spit9 in game test, looks similar to what you got in your test

 

Spoiler

 

it can save you some time if you dont wont to test every airplane, but considering there is no DDs heck why not test all again 2-3 .. 5 times before devs decide to give as some updates ?

 

[102nd-YU-devill]

Hi Count,

 

thanks, I had your earlier version I think (4.2) of the data but didn't realize there was an update.

How are we still having the superfast F4 and g2 in this game after so many years?

[CountZero]

Dont know if they have some secret data that shows all is ok or not but after so many years i doubt anything gona be changed now when they work on new game, it will be 97.5% accurate insted 95% ?

EDIT:

Just look at easyer example with something wrong with level speed for ages, no need to fight over real data, just in game prof that Fw is wrong, either A3 or A5, A6 and A8, all 4 can not be ok when you have this happening with their ata or top speed: Blue line that is so mutch off then other 3 abow 6,5km or at 2km is FWA3 

 

To me this looks like easy thing to fix, A3 is able to use to mutch ata at house points or A5, A6 and A8 are wrong and they need to be able to use same ata as A3 uses... no need to fight is WW2 data correct working airplane one or prototype one or broken one with some added drag= to elefant or is speed in 2% off from it and so on

 

I do not know how can you explain, if not bug, that out of 4 airplanes that are suposed to be similar one have so big deviation in ata/top speed at some alts. 

Edited February 28, 2023 by CountZero

[=RS=EnvyC]

The 190A3 has been busted since they changed the way the intake works on the BMW801, for some reason it was left out of the updates.

 

It's one of the reasons it's exceedingly popular online over the other variants.

[Roland_HUNter]

On 2/28/2023 at 12:00 AM, BlitzPig_EL said:

The G2 has been wildly overperforming for ages.

Why does it overperform?
This report says 525 km/h with automatic radiators.
http://kurfurst.org/Performance_tests/109G_Rechlinkennblatt/R_G1_Datenblatt.jpg

If you close it, you can achieve 535 km/h.

The brits did something wrong:
Here:
http://kurfurst.org/Tactical_trials/109G2_britg2trop/MET-109Gtrop_WdimPerf.html

They could achieve only 490 km/h.

The finns:

http://kurfurst.org/Performance_tests/109G_MT215/109G2_MT215_en.html#abberant

522 km/h.

 

Kuban summer-Auto rads:

 

Kuban summer-Closed rads:(overheats very quickly, you cannot keep it at this speed for long.)

[354thFG_Rails]

Not sure you can use the first link results of 525km/ and 535 as the weather conditions aren’t known or I’m missing where they are. The third you can try and recreate as it gives temps and atmospheric pressure that day. The British test I would not use either. As it was performed in the desert under unknown conditions and was a trop version. Which I would assume is slower and it looks like they were using the 1.3 rating. I’m not sure what devs tolerance is with speeds but I would think that if the G2 is within 10% of its speed listed in the Finnish test it’s probably pretty good. 

Edited March 8, 2023 by 86th_Rails

[357th_KW]

It's very helpful that the Finnish test above lists the exact environmental conditions.  I went ahead and created a series of custom missions set to that temperature and pressure, set at various altitudes for testing.  Here's a link to them for anyone who wants to test.  The results I got in a quick test were well in excess of what the Finn's got.  At sea level.  At 6300m.  At those atmospheric settings, that 6300m speed works out to 656 kph/408 mph true.

 

The British test above is actually really closely in agreement with Messerschmitt tests, when you note that it was an aircraft fitted with a tropical filter.  The Rechlin tests almost certainly didn't involve any correction of the data for compressibility or atmospheric conditions.  You can see in this Messerschmitt document (page 5) they have curves for both the 109G and the 190A5, and the Rechlin data is wildly high, particularly at high altitude (422mph for the 190A5 at around 7000m!).  It's also worth noting that the Rechlin data doesn't even include the curve in the 3-5km range where airspeed would dip due to losses from the fluid coupling, raising questions of how thorough this test data was, or if it was just some calculations instead.

 

As another point of comparison, here's Messerschmitt data involving a captured Spit V with a Merlin 45, which they then converted to a DB605A (Callum Douglas talks about this whole situation in his book, "The Secret Horsepower Race", and the project was largely about comparing the radiator function of the Spit vs the 109).  Their Spit V data is right in line with the British, for a Spit V at +9lbs boost.  And the 109 data is much more conservative then the Rechlin data.

Messerschmitt did a number of tests on G series aircraft and ALL of them are slower then what we get in game, by a lot in some cases.  An average of 4 standard production machines - 519 km/h at sea level.  A comparison of a G fuselage with a DB601E vs a DB605A - 504 km/h at sea level.  A test of a G-6 trop, with the old slim cowling, vs the double bumped cowling, vs the enlarged streamlined later cowling - 492 km/h at sea level. 

 

I think it's also worth bringing in a quote from Kurfurst's website talking about the 109F-4: "It is noticable that while the associated horsepower and the level speed results at Sea Level are practically identical, the two datasets show increasing seperation as altitude increases. Considering the aformentioned charasteristics observations of the two sets of data, and that most other Bf 109F-4 performance sheets and grahps repeatadly claim the 635 km/h value at the same power setting in agreement with the IV/78/42 calculated datasheet, it seems likely that the flight tested datasheet IV/43/42 is without compressibilty correction - the lack of such correction would characteristically result in increasingly higher instrument reading error with the increase of altitude, the read error levels peaking out at maximum speed at the rated altitude."

 

I think there's a really high likelihood that we're seeing that same issue here - the G-2 (and possibly all the other related 109s) was built off of data that didn't have compressibility correction applied. 

 

 

 

 

 

[IckyATLAS]

What would be interesting is not only to have readings in the cockpit about the speed but also do some reality checking.

 

This means to fly at the indicated speed say on a 10km stretch on the Kuban map defined by some markings on the ground or still ships at sea. You can even test differences with a fully populated map flying a 10km line over Krasnoiarsk city and same over the open sea empty except fro the two ship indicators.

You then clock with your wristwatch the time to fly this length and recalculate the real speed and see if it matches.

[the_emperor]

1 hour ago, 357th_KW said:

I think there's a really high likelihood that we're seeing that same issue here - the G-2 (and possibly all the other related 109s) was built off of data that didn't have compressibility correction applied. 

 

That actually might be in case of many flight test data. earlier 109s flight data (german and soviet alike) seems to be overperforming at high/FTH altitude. the best way is probably to look at the sea level top speed to compare where induced drag is the highest and the compressebility effect is lowest to compare airframe performance of the 109 variants.

For the G-1/2 wie find values from ~520-525kp (finish/german/soviet) though it is not always clear if the tailwheel is retractable. Climb time to 6000m is ~5 to 5.5min.

For the G-6 the common top level speed at sea level is 510kph. time to 6000m is 6min. (all with the 1.3/2600 Kampf&Steigleistung)

Edited March 9, 2023 by the_emperor

[Kurfurst]

On 2/28/2023 at 12:00 AM, BlitzPig_EL said:

The G2 has been wildly overperforming for ages.

Its not, its just wwiiaircraftperformance picking the worst 109G-2 test results ever made (Wnr 14026, which was a factory testbed used in various trials by Messerschmitt, and at the time of test comparing the same airframe with 601E and 605A built in was clearly underperforming - the run with the more powerful 605A was barely faster.

 

This is partly explained by its airframe conditions as the aircraft had with two different radiators (one copper, one dural), a non retractable tailwheel (that alone chopped down about 12 kph off from top speed at sea level), some indicators for the radiator flap position (-3 kph according to the report), and a tall tail unit, but I strongly suspect that the 605A it had was also down on power, which would explain why it showed very little increase over the same airframe with the 601E that nominally had cc 110 HP less. 
 

Then its poor results gets repeated since the Jan 1944 performance compilation is not even a test but a list of testbed results, most of which did not even had a complete speed run at all altitudes, but single altitude measurements for testing various equipment conditions. Essentially its a repetition of the same 14026 curves.

 

Then there is the May 1944 DB test results which weren't even for a G-2 but a (quite a bit more draggy) G-5 iirc. Its gets peddled by the site as a G-2 flight test.. ? 

 

There were numerous flight tests made on captured examples and German ones, and of course there is some variation due to mass production in specs. All of those are dismissed by the site with laughable reasoning: they are too fast to be displayed! Better stick to the lowest specs one can possibly find for those pesky Messerschmitts..
 

Anyways. The nominal figures given by the Germans for the G-2 were 660 kph at 7000 and 537 kph at SL, all at 1,3 ata, and with an understanding that the manufacturer guaranteed those specs within +\- 3% tolerance on speed. The low level specs seem a bit optimistic or need really, really optimum flying and conditions, but 530 seems perfecty doable, and in line with other flight test results, when corrected for the drag of the equipment on other airframes tested.

http://www.kurfurst.org/Performance_tests/109G_Erlatrials/Erla109G_13speedrun_scatter_web.jpg

 

This is very visible on Erla’s own test of 13 of its own series production planes (available at my site). The avarage result of all aircraft was about 652 kph top speed (1,3ata), with best planes licking into the 670s and poor ones barely going over 630. This was perfectly normal though, these were mass produced planes, some were excellent, some were lemons, most however near the official specs.
 

Note the Erla tests were done with 120mm wide open (cc 1/3 open) radiator flaps instead of the nominal 40-50mm opening (cc semi closed to 1/5 open) so results may have been even somewhat pessimistic due to higher radiator drag.
 

Now, to that it must be added that the Russians very throughly tested several G-2s captured at Stalingrad, not only for speed and climb, but also for less interesting things like stability etc. The ‘clean’ (no gondolas) plane achieved 666 kph at 7000 m in flight test. The other had two gondolas mounted, this did 650 at altitude, with the gondolas. This were a captured planes, tested exactly as used by Germans on the Russian front, and a well performing ones. 

 

There is hardly any more representative plane to represent a plane’s capabilities over the Russian front than the results of a plane actually flying over the Russian front, now is there..?

 

Bottom line - the G-2 was a damn fast plane for its time, amongst the fastest, even when somewhat neutered in its full potential at launch by Messerschmitts inability (or available engineering capacity) to mount the full undercarriage covers for the plane as originally intended (note the squared off wheel wells compared to the 109F), and Daimler-Benz’s struggle lasting about for a year to make the DB 605A push out its full power rating. With those two things done right and from the start, the G-2 had the potential to be in the 700 kph top speed region, not the 660s ‘only’… and that in mid-1942.

 

 

Edited March 10, 2023 by VO101Kurfurst
Added Erla flight test scatter

[=RS=EnvyC]

That data sheet is so barely legible to the point where we have no idea what it actually says nor if there were any corrections made for atmospheric conditions. It is significantly less detailed than the Finnish data set. German "tests" have a habit of being theoretical rather than measured so its hardly a reliable document given the alternatives.

If you could get a clearer version where we could actually get that information that would be much more useful.

Edited March 10, 2023 by =RS=EnvyC

[JtD]

There's no point in making "theoretical" accptance trials. This is flight data compared to specified data, all corrected by the same method, in order to make them comparable.

At that time for Messerschmitt data, this means correction to standard conditions and (very likely) no correction for compressibility, because that was standard procedure at Messerschmitt back then. Which would change the 652 production average to 638.

 

I find it strange that people laugh at accurate historical information instead of educating themselves on how to interpret it.

[Roland_HUNter]

8 hours ago, JtD said:

I find it strange that people laugh at accurate historical information instead of educating themselves on how to interpret it.

"How to interpret it.."

Do you know how many historian doing the same?
No objectivity, just "how to interpret things...."

 

[357th_KW]

I swapped my custom mission with the environmental conditions to match the Finnish tests to a G-4 for the added tailwheel drag (though I'm not sure if the Finnish aircraft had the bulges for the enlarged main wheels), and then tested at 1.3/2600rpm.  With the radiators closed, the results in game were:

 

sea level: +10 km/h

6300m: +4.5 km/h

8000m: +23 km/h (yes, 23 and not 2.3)

10000m: +64 km/h (yes, that's 64 and not 6.4) - with the radiators in auto this only dropped by 6 km/h.

 

Based on this I'd say the 109s are maybe a touch quick compared to that Finnish test below critical altitude, but overall fairly close.  Above critical altitude it gets crazy.

 

 

[102nd-YU-devill]

 

On 3/10/2023 at 2:33 AM, VO101Kurfurst said:

Its not, its just wwiiaircraftperformance picking the worst 109G-2 test results ever made (Wnr 14026, which was a factory testbed used in various trials by Messerschmitt, and at the time of test comparing the same airframe with 601E and 605A built in was clearly underperforming - the run with the more powerful 605A was barely faster.

 

This is partly explained by its airframe conditions as the aircraft had with two different radiators (one copper, one dural), a non retractable tailwheel (that alone chopped down about 12 kph off from top speed at sea level), some indicators for the radiator flap position (-3 kph according to the report), and a tall tail unit, but I strongly suspect that the 605A it had was also down on power, which would explain why it showed very little increase over the same airframe with the 601E that nominally had cc 110 HP less. 
 

Then its poor results gets repeated since the Jan 1944 performance compilation is not even a test but a list of testbed results, most of which did not even had a complete speed run at all altitudes, but single altitude measurements for testing various equipment conditions. Essentially its a repetition of the same 14026 curves.

 

Then there is the May 1944 DB test results which weren't even for a G-2 but a (quite a bit more draggy) G-5 iirc. Its gets peddled by the site as a G-2 flight test.. ? 

 

There were numerous flight tests made on captured examples and German ones, and of course there is some variation due to mass production in specs. All of those are dismissed by the site with laughable reasoning: they are too fast to be displayed! Better stick to the lowest specs one can possibly find for those pesky Messerschmitts..
 

Anyways. The nominal figures given by the Germans for the G-2 were 660 kph at 7000 and 537 kph at SL, all at 1,3 ata, and with an understanding that the manufacturer guaranteed those specs within +\- 3% tolerance on speed. The low level specs seem a bit optimistic or need really, really optimum flying and conditions, but 530 seems perfecty doable, and in line with other flight test results, when corrected for the drag of the equipment on other airframes tested.

http://www.kurfurst.org/Performance_tests/109G_Erlatrials/Erla109G_13speedrun_scatter_web.jpg

 

This is very visible on Erla’s own test of 13 of its own series production planes (available at my site). The avarage result of all aircraft was about 652 kph top speed (1,3ata), with best planes licking into the 670s and poor ones barely going over 630. This was perfectly normal though, these were mass produced planes, some were excellent, some were lemons, most however near the official specs.
 

Note the Erla tests were done with 120mm wide open (cc 1/3 open) radiator flaps instead of the nominal 40-50mm opening (cc semi closed to 1/5 open) so results may have been even somewhat pessimistic due to higher radiator drag.
 

Now, to that it must be added that the Russians very throughly tested several G-2s captured at Stalingrad, not only for speed and climb, but also for less interesting things like stability etc. The ‘clean’ (no gondolas) plane achieved 666 kph at 7000 m in flight test. The other had two gondolas mounted, this did 650 at altitude, with the gondolas. This were a captured planes, tested exactly as used by Germans on the Russian front, and a well performing ones. 

 

There is hardly any more representative plane to represent a plane’s capabilities over the Russian front than the results of a plane actually flying over the Russian front, now is there..?

 

Bottom line - the G-2 was a damn fast plane for its time, amongst the fastest, even when somewhat neutered in its full potential at launch by Messerschmitts inability (or available engineering capacity) to mount the full undercarriage covers for the plane as originally intended (note the squared off wheel wells compared to the 109F), and Daimler-Benz’s struggle lasting about for a year to make the DB 605A push out its full power rating. With those two things done right and from the start, the G-2 had the potential to be in the 700 kph top speed region, not the 660s ‘only’… and that in mid-1942.

 

 

I don't understand what you are talking about, there are many tests of Gs on the ww2aircraftperformance website which appear to be made by Germans themselves that clearly show 510kph or something like that at sea level for 1.3 ata. They are not British tests. 

 

To me it looks like the 109G2 in this game has the performance as if using 1.42ata while showing 1.3ata on the manifold pressure gauge.

It seems as simple as that.

 

Edit: Just to add something, in my tests above a 109G2 with a 30 min of combat rating at 1.3ata is equal or better in performance with a late Spitfire mk9e using +18 boost which is permissible only for 5 minutes. Seriously? I never heard before that Spitfires 9 were at such a speed disadvantage against contemporary 109s. I am afraid even to think what speed demon the g2 was using the later approved 1.42ata??? 

 

Edited March 14, 2023 by 102nd-YU-devill

[Roland_HUNter]

1 hour ago, 102nd-YU-devill said:

 

I don't understand what you are talking about, there are many tests of Gs on the ww2aircraftperformance website which appear to be made by Germans themselves that clearly show 510kph or something like that at sea level for 1.3 ata. They are not British tests. 

 

To me it looks like the 109G2 in this game has the performance as if using 1.42ata while showing 1.3ata on the manifold pressure gauge.

It seems as simple as that.

 

Edit: Just to add something, in my tests above a 109G2 with a 30 min of combat rating at 1.3ata is equal or better in performance with a late Spitfire mk9e using +18 boost which is permissible only for 5 minutes. Seriously? I never heard before that Spitfires 9 were at such a speed disadvantage against contemporary 109s. I am afraid even to think what speed demon the g2 was using the later approved 1.42ata??? 

 

http://www.wwiiaircraftperformance.org/me109/me109g.html

 

510 with gunpods?

"For average comparison values, 327 mph (527 km/h) at 820 ft altitude and 323 mph (520 km/h) at Sea Level is obtained with specially treated machines. The corresponding values of the standard production machines are 322 (519) and 318 mph (512 km/h). The speed increase thus averages 5 mph (8 km/h)."

[102nd-YU-devill]

16 hours ago, Roland_HUNter said:

http://www.wwiiaircraftperformance.org/me109/me109g.html

 

510 with gunpods?

"For average comparison values, 327 mph (527 km/h) at 820 ft altitude and 323 mph (520 km/h) at Sea Level is obtained with specially treated machines. The corresponding values of the standard production machines are 322 (519) and 318 mph (512 km/h). The speed increase thus averages 5 mph (8 km/h)."

 

So you quote 512 km/h for a standard machine at sea level and you ask if 510 km/s is with gunpods?

I'll give you the benefit of a doubt and assume you are arguing in good faith so I will just point to the fact that 510 is very close to 512 and very far from 535 which is measured in game with rads on auto.

In the same report you give a link where it is clear that standard (untreated) 109g at SL achieve anywhere from 504 to 515 km/h depending on the example.

These are all German tests. 

 

Anyway, I would guess that 535 km/h in this game at SL would probably correspond to 1.42 ATA cleared engine.

At the moment I didn't find how long the 109 could operate at that rating though.

According to wiki the 1.42 ATA was cleared in June 1943.

If the operation time at that rating was limited, then I would say a late Spitfire Mk9 with the Merlin 66 which we have in the game, using 18+ boost and 109G2 with 1.42ata are about evenly matched. 

And I would have absolutely no problem with that since from everything I ever read on WW2 dogfights in europe the Spit and the 109 were indeed very evenly matched when comparing contemporary variants.

 

However, in this game a supposed 1.3 ata G2 is 50 km/h (!!!) faster than a Spit 9e at the deck if the Spit runs out of the 5min emergency 18+ boost.

An the G2 can hold it for 30 minutes.

 

I am sorry but that's just wrong.

 

IL2 devs should implement correct speeds for 109g2 1.3ata and add a loadout option for a 1.42ata rated engine to be used from mid-1943 with a correct time limit of operation at maximum rating (whatever it is).

 

I can tell you from my tests that 109F4 seems to suffer from exactly the same issue.

With a 5-minute power rating (I forget what manifold pressure reads I will check actually 5-min is with 1.42ata so this is a 1942 f4) Bf109F4 in this game has the following performance:

 

 

As you can see, this is compared with the in-game Spitfire 9e Merlin 66 running at 18+ boost.

The Bf109F4 which is purported to be from mid-1941 is actually faster at high altitude than a Spitfire from the second half of 1943.

I don't have detailed speed charts on the Bf109F4 but it seems wrong to me that it should be faster at any altitude than a late Spitfire Mk9 which was supposed to be superior to the FW190 and ended the "butcher bird" onslaught. 

 

Edited March 15, 2023 by 102nd-YU-devill
Additional data presented

[JtD]

The Bf109F-4 was tested by Messerschmitt with 670 km/h at 6300m with Notleistung ("vmax=670 km/h (erflogen)", to quote the data sheet). Again, Messerschmitt data at that time was typically corrected to standard conditions but without correction for compressibility (which would put 670 into the 650 region). It was either as fast or faster than a Merlin 66 powered Spitfire at altitude. The F-4 was the fastest fighter aircraft of its time (this means 1941, early 1942, and at that altitude). It's not surprising that two years later, it was still competitive.

 

So speed and climb weren't really a shortcoming of the 109, until fairly late in the war, where you'd have the bumby G-6 with fixed tail wheel, bomb racks, gondolas and all the other draggy add-ons, but no MW50. Which achieved lower top speeds that the 3 year older f models. But in its good days, say up to the end of 1942, Bf109 tactics needed to employ speed, climb and dive to even out the Spitfires manoeuvrability advantages. Once the speed advantage was gone, or taken over by Spitfire, P-47 and P-51, the 109 had a really hard time on the western front.

That said, the advantages of the Fw190 wasn't really a higher top speed. It was about on par with contemporary 109's, really just somewhat faster at low altitude (1st supercharger gear), and slower at high altitude. The Fw190 brought high speed manoeuvrability, firepower, and the ability to disengage at will by diving out of trouble and then outrunning the competition at low altitude.

 

Anyway, if your issue is that

7 hours ago, 102nd-YU-devill said:

in this game a supposed 1.3 ata G2 is 50 km/h (!!!) faster than a Spit 9e at the deck if the Spit runs out of the 5min emergency 18+ boost.

then this is really more of a Spitfire issue than a 109 issue. Actually, more of an issue of the ? engine timer issue. The 109 might be performing slightly better than what the historical average could manage, but is within tolerances of historical performance and game target performance. It's not "wrong", in a binary sense. The Spitfire is quite alright, too. So, even with a couple of percent here and there wrong, you could still get a fairly realistic impression of relevative performance - if the Merlin did not give up after a few minutes.

Edited March 15, 2023 by JtD

[Roland_HUNter]

I would like to answer, but JtD did it for me.

 

I would like to add:
The Finnish report is still 522-525 Km/h with 1.3 ata.
F-4 Sea level:
1200 HP 1.3 ata
1350 HP 1.42 ata
G-2 Sea level:
1310 HP 1.3 ata
1480 HP 1.42 ata
Concrete with small differences in air resistance.

It is clear that the G-2 will be faster.
Again, it should be noted that the DB-605 A engine performed better at 6-7 thousand metres, so the G-2 is faster there too.

The G-4 can go 540 at sea level.
While the larger undercarriage has created bulges on the wing to accommodate the larger wheel, it also creates drag and the rear wheel is no longer retractable, which also slows the plane down.
 

Back to G-2:
516 km/h WITH tailwheel out.
http://www.wwiiaircraftperformance.org/me109/me109g-14003.html

525 Km/h, it's a G-1, Which is actually height 109, and few were made.

http://www.wwiiaircraftperformance.org/me109/Bf_109_G-1_Kennblatt_Flugleistungen.jpg

 

 

Correct me if I'm wrong, but the bigger and wider the wing of a plane, the more power it needs to reach the speed that a plane with a thinner, smaller wing area can reach.
Right?
So as far as I know, since this difference between the 109 and the spit can definitely be found, I don't see what's "wrong" with the F-4/then G-2 with a more powerful engine being faster than the spit.

[102nd-YU-devill]

On 3/15/2023 at 7:17 PM, JtD said:

The Bf109F-4 was tested by Messerschmitt with 670 km/h at 6300m with Notleistung ("vmax=670 km/h (erflogen)", to quote the data sheet). Again, Messerschmitt data at that time was typically corrected to standard conditions but without correction for compressibility (which would put 670 into the 650 region). It was either as fast or faster than a Merlin 66 powered Spitfire at altitude. The F-4 was the fastest fighter aircraft of its time (this means 1941, early 1942, and at that altitude). It's not surprising that two years later, it was still competitive.

I would hardly say competitive. If this performance could be maintained as long as the Spitfire M66 could maintain its maximum, then I would say Bf109F4 was a superior aircraft in late 1943.

What a mistake by the Germans to abandon it in favor of the G variant!!!

 

I never claimed that speed of a Bf109 should be a shortcoming; the 109 was always within a slim margin either faster or slower than its Spitfire counterpart. That margin was never (I am not counting very late war where many other factors greatly contributed to changing the balance of power) enough either way to upset a generally balanced fight: spitfire was a more nimble, 109 had better dive and acceleration performance. That put German pilots at a slight disadvantage as the Spit 9 started to fight G4s and early G6s which had lost some of the speed advantages yet did not improve on the strengths of the previous 109s, whereas the Spitfire had improved in all respects (except certainly dive speeds). 

But what are we taking about here? 

I am saying that in the case of G2 the performance in this game does not reflect the ATA reading in the cockpit. Our G2 is able to maintain performance (for 30 minutes) which should realistically be associated with a maximum engine rating of 1.42 and surely be more limited in time. 

 

Second, the F4 in the game seems to be the absolute best case scenario for the type, which is nowhere near its standard combat performance in 1941. Ok, if the Wiki and your numbers of 650, resp. 670 km/h are correct, then this is for the maximum rating which was not available before Feb 1942. However, I do not know the sources for these numbers so I can't say anything in which conditions were these numbers obtainable. 

 

If that speed was readily available for the F4, how come the British did not depict the F4 as the same menace as the FW190, seeing how it would have been easily outpacing the Spitfire by 50 km/h? That's quite a margin! 

Edited March 16, 2023 by 102nd-YU-devill
Adding response

[Yogiflight]

On 3/15/2023 at 8:24 AM, 102nd-YU-devill said:

With a 5-minute power rating (I forget what manifold pressure reads I will check actually 5-min is with 1.42ata so this is a 1942 f4) Bf109F4 in this game has the following performance:

1.42 ata is only for one minute, not for five minutes. The F4 doesn't have a power setting for five minutes. Just 30 minutes for combat power (1.3 ata) and one minute for emergency power (1.42 ata).

[102nd-YU-devill]

5 minutes ago, Yogiflight said:

1.42 ata is only for one minute, not for five minutes. The F4 doesn't have a power setting for five minutes. Just 30 minutes for combat power (1.3 ata) and one minute for emergency power (1.42 ata).

 

That doesn't really matter so much.

Here are comparative speeds from the game at combat ratings:

 

 

Man, that F4 is beating the M66 Spitfire, no problem!

 

[102nd-YU-devill]

On 3/15/2023 at 7:17 PM, JtD said:

then this is really more of a Spitfire issue than a 109 issue. Actually, more of an issue of the ? engine timer issue. The 109 might be performing slightly better than what the historical average could manage, but is within tolerances of historical performance and game target performance. It's not "wrong", in a binary sense. The Spitfire is quite alright, too. So, even with a couple of percent here and there wrong, you could still get a fairly realistic impression of relevative performance - if the Merlin did not give up after a few minutes.

This is really not true according to charts in ww2aircraftperformance website.

Again, if said performance is obtained with 1.42 ATA, then ok.

But the gauge in the game reads 1.3 ATA.

German tests of G2 clearly show 504-515 km/h at 1.3ATA at SL for G2.

535 km/h is for 1.42ATA and I doubt it can last for 30 minutes as is the case in the game.

[the_emperor]

So at quick test at Kuban Autumn at 1.3/2600  with rads on auto @ 25m

G2    ~535kph
G4    ~525kph
G6    ~510kph

 

tested at 6500m (indicated airspeed)

G2    ~467kph (~ 654kph TAS)
G4    ~457kph (~640kph TAS)
G6    ~466kph (~624kphTAS)

 

that does look reasonable at first glance, maybe a bit optimistic for the G-2/4 @ SL, but finding good reports, especially on the G-4 is not that easy.

the G-6 seems to be far better documented. the G-2 at least seems to be very optimistic presented at altitude.

The differences between these versions should probably decrease with altitude since the effect of parasite drag (with the G-6 beeing effected the most) decreases with altitude (IIRC the G-4 and G-6 are both rated with 630kph at FTH having a 10kph difference at SL, with that difference decreasing with altitude)

As it was mentioned before the speeds at altitude for the G-1/2 seen in german/soviet reports are probably not corrected for compressibility and are often above the FTH of the DB605A (~6400m-6600m)

 

Edited March 18, 2023 by the_emperor

[Kurfurst]

Results of TSAGI / NII VVS Trials on captured G-2 at 1.3 ata/2600

 

Bf 109G-2 with and without gondola guns fitted ('five gun' and 'three gun').

 

Bf 109G-2 WNr  14513 as captured and tested.

[Roland_HUNter]

Lagg-3 542? Wow ?

[Hanu]

11 minutes ago, Roland_HUNter said:

Lagg-3 542? Wow ?

At first it may sound surprising, but after all it is a reliable TSAGI document. ?

[CUJO_1970]

2 hours ago, Roland_HUNter said:

Lagg-3 542? Wow ?

 

And FW190A-4 510

[ICDP]

Wasn't that VVS Fw190 a repair job on a crash landed example?

Edited March 22, 2023 by ICDP