Wrong Russian fighters performance at high alts again

[novicebutdeadly]

What's interesting is that when the game was under development when they first introduced the cold air element, the LAGG (only Russian fighter at the time) had a massive performance boost, whereas the 109F4 (only German plane) seemed to have no increase/ performance decreased (I discovered this because I had used the same tactic and could clearly see the massive change in the performance of the LAGG).

I have watched this particular thread with both interest and bemusement, and thought that perhaps the developers can shed some light on a particular question:

If the game is not skewed towards giving the Russian planes more performance that what they had (speed/roll/ turn time/ energy retention/ Rate of acceleration etc), why is it that whenever the game loads a mission and the loading screen has both a Russian and a German plane in the picture, why is the German plane always being shot down, but never a Russian plane being shot down (unless for some strange reason only my game has this......)

Even when we see 2 109's attacking an il2, the il2 gunner is landing hits, and critical hits on the lead 109, which doesn't seem to be able to hit the side of a barn.

109 attacking a truck yet the 109 can't hit squat, yet il2 shown flying over a decimated train......

How can we believe that this game is not bias when we see clear Soviet propaganda? 

Edited February 20, 2015 by novicebutdeadly

[unreasonable]

Perhaps BoM is getting funding from the Imperial Russian Historical Society like the recent RoF add-on?

[303_Kwiatek]

It was standard serial plane from production.Series 99 was october/42 production,tested plane was nr.16 of that 99.series.Switching from PA to PF increased speed by 20-24km/h finaly meeting I26-2 prototype performance.Further aerodynamical improvements increased it ,if only marginaly (+3-6km/h for later series from 111. till the last 192.).Personaly,I think that Stepanec is quite an authority for yaks.So if devs used his data,then someone should perform new test at 5km if yak can get to 574km/h TAS.I cant do that,out of my gaming PC for at least another week.

 

You forgot that we have in game 69 series of Yak so much earlier series.  So these data is not accurate for it.  Important is take off weight and data for similar take off weight for Yak-1 from 1942 with M-105 PF engine was as i wrote above :  500-510 kph at 0  and 570 km at 3.65 km.

 

Kwiatek can you give me the link of your Tas calculator? I will compile a proper report the next days about high altitude imbalance between the planes and sent it to Han.

Don't see any point anymore to discuss in the forum, because anytime you find some flaws there are just to many people trying to highjack your concerns, with any methods available..no matter how obvious the flaws are. It was exactly the same back then with the 190

 

Sure here is very good aviation calculator

 

http://www.hochwarth.com/misc/AviationCalculator.html

[CaK_Rumcajs]

How can we believe that this game is not bias when we see clear Soviet propaganda? 

It's more an simulation issue. The best fighter plane in the game is still the Bf 109F4, which has also received some unexpected boost based on Kwiatek's findings. The Yak, F4 and LaGG performance has probably more to do with not exactly fine tuned simulation of the AC. There may be some intention to help some planes in order to make the game playable for both sides. But that will stand no ground in the long run. Such approach creates relative performance hell when new AC are added. And because there is a mutual interrest in new content creation these problems will be fixed over time.

[303_Kwiatek]

How can we believe that this game is not bias when we see clear Soviet propaganda?

 

It's more an simulation issue.

 

There are many other simulations issues suprisly also mostly with Russian planes e.x. very doubfull roll rates of LA5 and LAgg3, reduced nasty spin charactersitic of Lagg3 and overdone of Fw 190 and maximum safe dive speeds of all Russian planes   German planes cant be official worse casue there is too much hard data which said otherwise but such small issues is different story

Edited February 20, 2015 by 303_Kwiatek

[CaK_Rumcajs]

Yep i know Kwiatek, but there is no way the roll rates are here to stay. Once we move on the time axis towards Kursk, the La 5FN would have to go through the roof with its improved handling. And I'm pretty sure we get there in some time. Probably not this year. But till then we'll be hearing constant "Are we there yet?".

[=EXPEND=Tripwire]

While I appreciate the time being spent to help correct any flight model issues, I am dissapointed to see posts stating the developers choose to do this on purpose rather than it being a potential error.

 

Why not be more professional in the approach - highlight the issue (like has been done) back it up with tests (also done) and then leave the claims that the game is a source of Russian propaganda out of it. 

 

I'm sure it does nothing but damage the credibility of the claims in here.

 

Like I said before though - Thank you for the time invested testing and attempting to get potential flight model errors corrected!

[303_Kwiatek]

Unfortunately devs attitude regarding these issues hardly allow to think something different.

Edited February 20, 2015 by 303_Kwiatek

[novicebutdeadly]

While I appreciate the time being spent to help correct any flight model issues, I am dissapointed to see posts stating the developers choose to do this on purpose rather than it being a potential error.

 

Why not be more professional in the approach - highlight the issue (like has been done) back it up with tests (also done) and then leave the claims that the game is a source of Russian propaganda out of it. 

 

I'm sure it does nothing but damage the credibility of the claims in here.

 

Like I said before though - Thank you for the time invested testing and attempting to get potential flight model errors corrected!

The problem with BOS has always been in regards to Russian fighters; in that the community can only go by the info they read (on the net etc) and how it matches up in game.

 

When they see a discrepancy they try to bring it to the attention of the developers (who as you have said have done an outstanding job).

 

Unfortunately the developers are unwilling to post what they have read to give the community a chance to prove a case, or see that they (the community) were wrong (for whatever reason).

 

A very simple example is that Russian planes had a lower max dive speed than German aircraft, if they went over that speed they would loose a wing (which has been accurately modeled in prev sims), yet in BOS you can dive a YAK from 6km to SL reaching circa 1040km/s (IAS when you impact the ground) and have only lost your control surfaces (ailerons, rudder, and elevators) at a much higher speed than normal (you start to loose them at circa 750 km/h).

 

There is no uncontrolled snaking etc.

 

 

Based on the loading screens it's hard to think otherwise in regards to if the game is skewed to one side.

 

 

To be honest if note the term IF the devs did skew the game to keep it fair, perhaps instead of doing that they should have just started in 1944. And then maybe worked their way back in history.

 

 

 

Edited February 20, 2015 by novicebutdeadly

[=362nd_FS=Hiromachi]

The problem with BOS has always been in regards to Russian fighters; in that the community can only go by the info they read (on the net etc) and how it matches up in game.

Are they really ? Any time I fly online there are plenty of guys eager to go with 109s but few wishes to fly USSR warbirds. If I fly on Syndicate or DED its usually same story of Germans beating Soviet aircraft over the Soviet airfield, rarely other outcome.

 

 

 

Unfortunately the developers are unwilling to post what they have read to give the community a chance to prove a case, or see that they (the community) were wrong (for whatever reason).

Havent seen War Thunder or DCS developers doing anything similar to that. On DCS Yoyo can give you a fine and fair arguments but wont present you documents he used.

 

 

 

Based on the loading screens it's hard to think otherwise in regards to if the game is skewed to one side.

Seems some are still mentally stuck in Cold War.

 

Anyway, this offtop lead us nowhere. Kwiatek has a data, he can compile a pdf report and send it to Han or Zak. 

[Brano]

You forgot that we have in game 69 series of Yak so much earlier series.  So these data is not accurate for it.  Important is take off weight and data for similar take off weight for Yak-1 from 1942 with M-105 PF engine was as i wrote above :  500-510 kph at 0  and 570 km at 3.65 km.

TBH I believe more what Stepanec writes then any other source.He clearly states that when Yak 1 switched from PA to PF engine,there was increase of 20-24km/h.Together with more aerodynamical tweakings and improvements.Aircrafts commited for state tests were of 85. and 99.series.No record of 69.series testing in his book.So for me anything inbetween 570-589km/h is a legit value.

My last input here: aerial combat is not executed at max speeds.So this theoretical horizontal level speed test are of little concern for me.Even at 6km,where Yak is a flying brick with almost nonexistent climb (2-4m/s).And I never fly Yak or LaGG at such altitudes.I am not masochist

I am concerned about vysotnyi korrektor and how game (does not) represent mixture settings and engine behaviour at high alts.

[II./JG77_Manu*]

Are they really ? Any time I fly online there are plenty of guys eager to go with 109s but few wishes to fly USSR warbirds. If I fly on Syndicate or DED its usually same story of Germans beating Soviet aircraft over the Soviet airfield, rarely other outcome.

That's probably because at this time German planes have been still miles ahead the russian ones. Even if you buff the Russian ones (like Yak in game) they are still behind the 109. Btw La5 should be the best performing Russian bird in game and not the Yak. I was really baffled when i realized the performance difference in game between those two. The first Russian plane to reach German performance spheres was the La5Fn. And not the Yak 1

 

 

TBH I believe more what Stepanec writes then any other source.He clearly states that when Yak 1 switched from PA to PF engine,there was increase of 20-24km/h.Together with more aerodynamical tweakings and improvements.Aircrafts commited for state tests were of 85. and 99.series.No record of 69.series testing in his book.So for me anything inbetween 570-589km/h is a legit value.

My last input here: aerial combat is not executed at max speeds.So this theoretical horizontal level speed test are of little concern for me.Even at 6km,where Yak is a flying brick with almost nonexistent climb (2-4m/s).And I never fly Yak or LaGG at such altitudes.I am not masochist

I am concerned about vysotnyi korrektor and how game (does not) represent mixture settings and engine behaviour at high alts.

 

20-24 at which altitude? PF was low altitude performance engine, so maybe at ground level you are right. But i highly doubt that at altitude it was the same. And all sources beside your Stepanec say the same, 571 topspeed. They all meat in all the other specs as well. Only your Stepanec, who is talking about a difference model by the way has difference numbers. So next time we got a G6, we just use the boost-injected AS version as reference, or what?  (i know, that's never gonna happen in a Russian game). But apart from that..the Yak in game is also a lot better then the Stepanek reference. It almost reaches the Yak3 performance at 6000m.

Edited February 20, 2015 by Celestiale

[6./ZG26_5tuka]

That's probably because at this time German planes have been still miles ahead the russian ones. Even if you buff the Russian ones (like Yak in game) they are still behind the 109. Btw La5 should be the best performing Russian bird in game and not the Yak. I was really baffled when i realized the performance difference in game between those two. The first Russian plane to reach German performance spheres was the La5Fn. And not the Yak 1 :rolleyes:game is also a lot better then the Stepanek reference. It almost reaches the Yak3 performance at 6000m.

Indeed The first series of soviet fighters (Mig-3, Lagg-3, Yak-1) were build using the knowledge of the bf109 E gained during the final days of the german-soviet treaty. The Friedrich on the other hand posed a unpleasant suprise and quickly showed it's superiority on the eastern front. By the time, though, the Russians hardly could afford improving their models already in production so they kept mass producing their inferiour types (most of them had to be extensively modyfied by troops on the airstrips since Stalin forbid any changes during production.

 

Anyway the Yak is clearly modeled wrong and needs to be adressed so do the F-4, Lagg-3 and La-5. If people will fly germans for the main part we need better server structuring to limit numbers of german players vs VVS, though discussion doesn't fit in a FM data thread aiming for historical accurancy in aircraft performance.

Edited February 20, 2015 by Stab/JG26_5tuka

[DD_Arthur]

While I appreciate the time being spent to help correct any flight model issues, I am dissapointed to see posts stating the developers choose to do this on purpose rather than it being a potential error.

 

Why not be more professional in the approach - highlight the issue (like has been done) back it up with tests (also done) and then leave the claims that the game is a source of Russian propaganda out of it. 

 

I'm sure it does nothing but damage the credibility of the claims in here.

 

Like I said before though - Thank you for the time invested testing and attempting to get potential flight model errors corrected!

 

I quite agree with this.  This is an interesting and relevant topic but accusation of deliberate developer bias or "balance" is wholly uncalled for and hardly original.  It says rather more about the character of the people making such accusations - despite direct denials by the dev team -  than any potential intentional flaw in FM's.

 

In view of what the team are working on we need a little bit more patience and just concentrate on getting more information into this thread.  As we've seen in the past, they'll answer after a fashion.  Whats needed is solid info. rather than accusations.

[novicebutdeadly]

I quite agree with this.  This is an interesting and relevant topic but accusation of deliberate developer bias or "balance" is wholly uncalled for and hardly original.  It says rather more about the character of the people making such accusations - despite direct denials by the dev team -  than any potential intentional flaw in FM's.

 

In view of what the team are working on we need a little bit more patience and just concentrate on getting more information into this thread.  As we've seen in the past, they'll answer after a fashion.  Whats needed is solid info. rather than accusations.

Most people when pointing out an incorrect FM etc have given their own opinion as to why that bias exists (most of which is giving the Devs the benefit of the doubt), which provided it is done respectfully they are allowed to do.

 

I'm not sure how it "say's something about the character of the person making such accusations", when that should depend more on the way they express/articulate their POV, as opposed to them just expressing their POV

 

Posting a question like I did in regard to Russian "propaganda" I believe was only fair, and was the only term that I felt was valid

 

We have seen the Dev team (who have done an awesome job so far) say that there is no bias etc, yet as I posted when the missions load, whenever there is a Soviet and German plane in the image, the German plane is in the process of being shot down. This to some shows at worst an undeniable bias, or at best a denial of history.

 

I questioned as to why the Soviet planes  don't loose wings in dives, which historically they did.

 

All I am doing is pointing out my observations, which as far as I am aware I have done without attacking anyone (community or Dev), and look forward to constructive conversation in regards to them.

 

 

 

 

 

 

Edited February 20, 2015 by novicebutdeadly

[Rama]

without attacking anyone (community or Dev)

 

Russian "propaganda"

This to some shows at worst an undeniable bias, or at best a denial of history

 

Acusing the dev of bias, denial of history or of displaying propaganda is an attack.

So please don't say you're not attacking anyone.... you clearly are.

 

Now you know it, better stop it and make your point was valid arguments, like technical information and data.

[LukeFF]

Unfortunately devs attitude regarding these issues hardly allow to think something different.

 

Utter nonsense. 

[Sokol1]

 

http://www.hochwarth.com/misc/AviationCalculator.html

 

OT - Just as curiosity. The IL-2 FB IAS-TAS chart (4000 meters 400KMH IAS) in this calculator (If I use the correct function). 

 

Edited February 21, 2015 by Sokol1

[novicebutdeadly]

Acusing the dev of bias, denial of history or of displaying propaganda is an attack.

So please don't say you're not attacking anyone.... you clearly are.

 

Now you know it, better stop it and make your point was valid arguments, like technical information and data.

Ok I will keep it simple without taking the observations to their logical conclusion.

 

 

During the loading screens which everyone see's (so need to provide images):

 

* Why is it when both a Russian plane and a German plane are present, why is it that only the German plane is being shot down?

 

* Why do we not see the German's achieving any success with ground attack, but we see Soviet success?

 

 

Perhaps I am being too sensitive, however one of the subjects I studied in highschool taught me all too well how to analyse photo/ images in order to see their purpose. 

 

Unfortunately there is only one purpose that I can see, and I had hoped to see how I could be wrong through other people comments.

 

 

 

Edited February 21, 2015 by novicebutdeadly

[DD_Arthur]

Ok I will keep it simple without taking the observations to their logical conclusion.

 

 

 

 

I fear your logic is faulty.

[novicebutdeadly]

I fear your logic is faulty.

 

Fair call, please explain.

[JtD]

Still no real life test data of a Yak-1 of near s69? Just a couple of figures from books? Has anyone checked the Russian forum, in particular as Zak has hinted that there are even bigger FM discussions? Maybe there the devs at least stated what they based their performance on?

 

I still think there's little point in convincing the devs of errors in the FM if the errors are in their sources.

[Crump]

 

 

A very simple example is that Russian planes had a lower max dive speed than German aircraft,

 

Not necessarily. The PEC curve on some of the Russian aircraft is different.  The Lagg-3 for example, depending on the design modifications had anywhere from a slightly lower Vne to the same Vne as the Bf-109G series. 

[6./ZG26_5tuka]

Not necessarily. The PEC curve on some of the Russian aircraft is different.  The Lagg-3 for example, depending on the design modifications had anywhere from a slightly lower Vne to the same Vne as the Bf-109G series. 

Still doesn't mean pilots were capeable of pullng up at that speed though, which leads us back to the manual recommended ~600 km/h Vne.

 

The 109 also had models with modyfied controll surface and enhanced structure for better diving speed, so we likewise could use their data to model all 109s ingame.

[=362nd_FS=Hiromachi]

Still doesn't mean pilots were capeable of pullng up at that speed though, which leads us back to the manual recommended ~600 km/h Vne.

While I agree that on some VVS birds the dive limits is not meeting the expectations and exceeds what we've heard, and I think that should be reviewed and possibly fixed if mistake exists.

But especially you should know that dive limits in manuals were taken with safety measurements, to keep pilots away from dangerous regions. Japanese A6M2 had a dive limit in manual standing as 630 km/h Indicated, however the actual tests in 1940 shown that it can safely to 680 km/h Indicated and airframe was in one piece. There are also plenty of other examples such as Spitfires or other machines you name, For example, the upcoming Macchi 202 is interesting. On August 21 1941, in Lonate Pozzolo, Lieutenant Giulio Reiner, carried out the test flight and the instruments on board recorded the dive speed, reaching 1,078.27 km/h. 

[6./ZG26_5tuka]

True that Hiro, but there still should be a noticebaly difference between the 109's and Lagg-3's real Vne (assuming both sides used roughtly the same ammount of tolerance in manuals for safety sake). Interistingly ingame planes actually don't rip apart when exeeding their (ingame) Vne but lose their controll surfaces - that one kept me curious for some time now.

 

We also need to consider speedometer arrors when talkign about test pilot data. Even today mechanical speedometers have a certain ammount of inaccurancy increased by changes in air pressure and temperature.

 

To not make it ride off topic for too long I didn't mean to say 600 km/h should be a "dead number" you'll crash and burn once reaching but a value to consider for pilot safety. If the structure has the strengh to exeed this value by a great ammount (as Crump claimed) there must be a different reason for the manual stated Vne making diving at high speed risky with the lagg-3.

Edited February 21, 2015 by Stab/JG26_5tuka

[=362nd_FS=Hiromachi]

Right, I wont get into the dive limits but after two weeks of sweet holiday time to get back to my studies. In the meantime I also returned to my library with huge amount of documents and I finally could put finger on TSAGI documents describing all VVS warbirds from 1917 to 1945 with engine power curves, plane performance curves and other features. Its in Russian language with which I'm not familiar but graphs dont require that much of language knowledge. 

 

So coming back to original report done by Kwiatek (You have btw. my full respect for the time you gave to test this ) :

 

------------------------Lagg -3 ----------------------------------Yak-1----------------------------La5----------------------forzah

Sea level------------538 kph (all radiator 25%)-----------553 kph (25%)-----------------530 kph ( 25 %)-------567 kph ( 25%)

------------------------543 kph (radiator 0%)----------------560 kph ( 0%)------------------539 kph  ( 0%)--------575 kph (0%)

RL TAS -------------507 kph--------------------------------- 500-510 kph--------------------509 kph-----------------535 kph

 

6 km----------------437 kph/585 TAS ( 25 %)-----------449kph/601 TAS ( 25 %)-------440 kph/589 TAS ( 25 %)----------------------

----------------------443 kph/593 TAS (0%)--------------457 kph/611 TAS ( 0 %)--------444 kph/595 TAS  ( 0%)------------------------

 

RL TAS-------------535 kph -------------------------------540-550 kph-----------------------------580 kph

 

Maximum speed---560-566 kph/3.6 km?--------------570 kph/ 3.65 km---------------------580 kph/ 6.2 km

 

From my test it is clearly show that Yak-1 and Lagg-3 got not low altitutde engine but rather high alts engines in BOS.  Both are about 50-60 kph too fast at 6 km.  Thats why German planes don't have in BOS their RL advetntages at higher alts. IRL German fighters ( 109 and Fw 190 A-3) was faster then Yak-1 about 80-100 kph TAS at alts above 5 km.
So its looks that Yak-1 and Lagg-3  performacne expecially at high alts need big revsion.  50-60 kph too more is really huge error.

 

 

 

Other hand all known suorces claim for Yak-1 and Lagg-3 from 1942 year with M-105 PF engine not more then 570 kph at 3.6 km. 

 

 

 

So how you explain that Yak-1 with M-105 PF motor  in BOS  at 6 km  reach  611 kph TAS  when IRL it should be not faster then 540-550 TAS kph?

Yak-1 and LaGG-3 are too fast by 50-60 kilometers per hour.   

 

Than we have what Brano posted :

 

Before        After

                                              improvement      

    Маx speed, км/h

    ground level .....................     516           523

    1st critical altitude ................ 565 (1950 м)  568 (1850 м)

    2nd critical altitude ................ 589 (3950 м)  595 (3850 м)

    At 5000 м ............            .....574           579

 

Yak-1 with older M105PA engine

    Маx speed, км/h

    ground level .....................     471-473          

    1st critical altitude ................ N/A  

    2nd critical altitude ................ 560-573 (4860м)  

 

That was considered as unreliable source, doubtful.

 

Well, I scanned a table and graph :

 

 

This seems to be consistent with what Brano posted, the performance improvement of Yak-1 at all altitudes with the top speed of ~590 km/h at ~4000 meters. Than we see a drastic drop in performance, as it was properly indicated, Klimov M-105PF is a low altitude engine. At 5000 meters plane makes about 575-579 km/h and at 6000 performance reaches about 570 km/h.

 

With the 2 % mistake margin that would give at best 581 km/h.  So depending on the estimation Yak-1 is possibly 20 to 30 km/h too fast. While it seems to exist I doubt most can actually "feel" it as its "corner performance", 95 % of the time players are either above (diving) or below (climbing, turning, etc.) the top speed. 

 

But well, I hope I found something more consistent and still I think Kwiatek should make use of his hard work and compile a report. 

[JtD]

It is however a 1943 Yak-1 as described below the chart, result of aerodynamic refinements and improved production quality control. More representative for 1942 and Stalingrad is the green line in the "A" group, given with 540km/h @ 6000m - a version of June 1942.

Edited February 21, 2015 by JtD

[=362nd_FS=Hiromachi]

It is however a 1943 Yak-1 as described below the chart, result of aerodynamic refinements and improved production quality control. More representative for 1942 and Stalingrad is the green line in the "A" group, given with 540km/h @ 6000m - a version of June 1942.

The "A" is version with Klimov M 105PA engine, while we are supposed to have PF dont we ?

[303_Kwiatek]

M-105 PA series got higher supercharger settings and achived maximum speed at higher alts.

 

No doubt section A is for 1942 and section B for later series in 1943 ( Lagg is surly 66 serie from 1943). Both section A and B are equimpent with M-105 PF engine on these chart.

Edited February 21, 2015 by 303_Kwiatek

[JtD]

No, it is a PF version. The PA had a considerably higher full throttle altitude, check for instance page 36. Top speed of the early Yak is reached at around 5000m, instead of below/around 4000m.

[303_Kwiatek]

These is the best representative chart for Yak-1 series.  It is only need to know how to read it (  important is also take off weight, armament equimpent etc.). 

 

You dont find more reliable source.   It is from book Soviet Combat Aircraft WW2. 

 

These data are confirmed even by Russian sources.  As Russian chart posted above.

 

 

 

 

 

 

[=362nd_FS=Hiromachi]

No, it is a PF version. The PA had a considerably higher full throttle altitude, check for instance page 36. Top speed of the early Yak is reached at around 5000m, instead of below/around 4000m.

You know, that far I can read Russian language, and no. The page 36 refers to Yak-1 from 1940 with Klimov M-105P

М-105П    -   M-105P

М-105ПА  -  M-105PA

М-105ПФ  -  M-105PF

 

Yak-1 from 1940 with Klimov M-105P had a lower speed on deck - 480 km/h. 

[303_Kwiatek]

Yak -1 with M-105 PA version got similar maximum speed as M-105 P version  (10-20 kph diiference depend of series and year) but maximum speed was achived in both these engines at near 5km.  For PF engine at near 4 km.  So 1 km below.   All these Russian charts say everything and regarding Russian planes i think are quite accurate.  Chart which i posted show similar results.  How you can't see such obviously things?

 

Yak-1 from 1942 with M-105 PF engine at about 2900 kg armament 1x20mm, 2x 7.62 mm achived 500-510 kph at deck and 570 kph at 3.6 km. These is Yak before aerodynamic improvements ( before 99 serie). Exacly like we got in BOS.

 

BTW Lagg-3 from 1940 year ( from chart) is pre war early version, Lagg-3 in 1941 was much worse in performacne. Much worse.

 

Difference between 105- PA and PF engine. 

Edited February 21, 2015 by 303_Kwiatek

[JtD]

You know, that far I can read Russian language, and no. The page 36 refers to Yak-1 from 1940 with Klimov M-105P

 

Yak-1 from 1940 with Klimov M-105P had a lower speed on deck - 480 km/h.

"And no"? What exactly are you disagreeing with?

[=362nd_FS=Hiromachi]

Here is the following quote from the book :
 

 

Максимальная скорость увеличилась: у земли - на 27 км/ч, на высоте  5000  м  - на 7 км/ч.  Относительно малый прирост максимальной скорости с подъемом на высоту объясняется  сни-жением границ высотности.

Время набора высоты 5000 м уменьшилось примерно  на  0,8 мин, время  выполнения  виража  на высоте 1000 м - на 0,5 с, набор высоты за боевой разворот с начальной  высоты  1000  м увеличился на 150 м, длина разбега при взлете уменьшилась на 45 м.

Yak-1 with only engine switched from M-105PA to M-105PF had increased speed by 27 km/h on deck and 7 km/h at 5000 meters. That is consistent with the table you presented on a previous page.

 

However, the engine replacement was done on the earlier Yak-1, previously running on M-105 PA.

This switch was done on June 1942.

 

But the first serial production Yak-1 with M-105 PF came out of the factory later and passed trials in September 1942. 

 

Первый серийный Як-1  М-105ПФ  (N29-85  выпуска  августа 1942  г.)  проходил  контрольные государственные испытания в HИИ ВВС в сентябре 1942 г. [ЦАМО, ф. HИИ ВВС, оп. 485655, д. 160] Испытания проводила бригада в следующем составе: летчик В.И.Хомяков, инженер М.А.Пронин и техник В.Ф.Сбитнев.

Самолеты  Як-1 М-105ПФ  успешно использовались в Великой Отечественной войне начиная с битвы под Сталинградом, с осе-ни 1942 г.

 

The serial Yak-1s with M-105PF differed from the previous with some changes to the cooling system:

 

По результатам испытаний перед HКАП был поставлен вопрос о необходимости переделки  системы  охлаждения  двигателя  и принятия мер  по предотвращению выбивания масла из суфлера и уплотнений двигателя,  что и было осуществлено (исключая вы- бивание масла через уплотнения)  на серийных самолетах  Як-1

М-105ПФ более поздних выпусков.

 

The improvements done in 1942 gave the overall increase of the performance by 20 km/h, while in 1943 the average performance of the flying machines is as follows :

 

   Столь малое повышение максимальной скорости Як-1 М-105ПФ N23-148 объясняется тем, что на серийных Як-1 поздних выпус- ков ресурсы    улучшения   аэродинамики   были   практически исчерпаны [Hапомним,  что в 1942 г.  увеличение максимальной скорости вследствие  улучшения  аэродинамики составило около 20 км/ч.].

    По данным ЛИИ [ЦАМО,  ф. HИИ ВВС, оп. 128661, д. 63.], в 1943 г.  средние значения летных характеристик серийных Як-1 составляли:

 

Максимальная горизонтальная скорость, км/ч

    у земли ...................................................    531 +6/-4

    на 1-й границе высотности   .............    568 +3/-4

    на 2-й границе высотности   .............    592 +3/-6

Границы высотности, м

    1-я. ............................................................ 1700 +175/-225

    2-я   ................................... ........................4100  +60/-250

Прирост высотности, м

    на 1-й границе высотности ...............      1200

    на 2-й границе высотности ...............      1400

Время набора высоты 5000 м, мин .....   5,6 +/-0,5

 

So being honest, what exactly was the 69th series and how it was improved I could not find. Only thing that is written is that the Yak-1 with M 105-PF not only differed with the engine.

 

 

 

"And no"? What exactly are you disagreeing with? 

That page 36 refers to M 105 PA. It does not, it refers to M 105 P. Nothing more.

[303_Kwiatek]

Yak-1 with only engine switched from M-105PA to M-105PF had increased speed by 27 km/h on deck and 7 km/h at 5000 meters. That is consistent with the table you presented on a previous page.

 

 

At low alt PF engine give some boost but at above 4 km not. Simple PA engine got more power the PF at 5 km.

 

Reading is one thing reading and thinking is another story.

[JtD]

That page 36 refers to M 105 PA. It does not, it refers to M 105 P. Nothing more.

OK, I thought you were disagreeing with something I said. Never mind.

[=362nd_FS=Hiromachi]

 

 

Reading is one thing reading and thinking is another story.

Spare yourself such comments, you've already shown in the thread lack of tact.

 

The engine was installed on that Yak-1 with further changes to the cooling system and other elements :

 

В связи  с установкой нового двигателя осуществлены сле дующие доработки: установлен маслорадиатор ОП-352 с большей охлаждающей поверхностью; изменена, форма гондолы маслорадиатора;  с туннеля водорадиатора снята предохранительная сетка.

Установка форсированного по  наддуву  двигателя  М-105ПФ позволила не  только полностью восстановить сниженные в процессе  серийной постройки  летно-тактические  характеристики Як-1 до уровня характеристик опытного самолета И-26-2,  но и существенно  улучшить  их.

That in general restored the decrease of the performance existing in serial production models until the change to M 105-PF.

[303_Kwiatek]

Столь малое повышение максимальной скорости Як-1 М-105ПФ N23-148 объясняется тем, что на серийных Як-1 поздних выпус- ков ресурсы улучшения аэродинамики были практически исчерпаны [Hапомним, что в 1942 г. увеличение максимальной скорости вследствие улучшения аэродинамики составило около 20 км/ч.]. По данным ЛИИ [ЦАМО, ф. HИИ ВВС, оп. 128661, д. 63.], в 1943 г. средние значения летных характеристик серийных Як-1 составляли: Максимальная горизонтальная скорость, км/ч у земли ................................................... 531 +6/-4 на 1-й границе высотности ............. 568 +3/-4 на 2-й границе высотности ............. 592 +3/-6 Границы высотности, м 1-я. ............................................................ 1700 +175/-225 2-я ................................... ........................4100 +60/-250 Прирост высотности, м на 1-й границе высотности ............... 1200 на 2-й границе высотности ............... 1400 Время набора высоты 5000 м, мин ..... 5,6 +/-0,5

 

These clearly show performacne of Yak-1 from 1943 after aerodynamic improvements.  Russian achived about 20 kph max after these improvements.  So Yak-1 from 1943 reached 531 kph at deck and 592 kph at  2 gear of supercharger ( around 4 km).   Its exacly confirm performacne of earlier Yak-1 from 1942 year.    Remove 20 kph from these results and add some weight for 1942 Yak-1 and you will got its performance.  Exacly about 510 kph at deck and 570 below 4 km.

 

Nothing more to add.

Edited February 21, 2015 by 303_Kwiatek