Yak-1 Airspeed Down On The Deck

[II./JG77_Manu*]

 

 

"the Fw190 gained on the Bf109 at all altitudes, the steeper and longer the dive, the larger the lead. However, also in dives the Bf109 reaches top speed faster than the Fw190." The Bf109 in that comparison had superior dive acceleration

Think you have been misinterpreting something here. It only says the 109 reaches it's own topspeed faster then the 190 it's own one. So 109 is faster on 750kph then 190 on 850kph. Nothing else. Nothing about "superior dive acceleration". Beside that A2 has 10% less power then A3, which has also be taken into account in the test.

[6./ZG26_5tuka]

From: http://www.beim-zeugmeister.de/zeugmeister/index.php?id=24&L=quxylvppeool

 

Which automaticly shows up the need to know what has been considered max speeds for the Fw 190 A-2 and Bf 109 F-4 in this test.

Edited March 10, 2015 by Stab/JG26_5tuka

[JtD]

Since they are discussing this immediately after the level acceleration test, where the Bf109 was better than the Fw190, I wonder what you guys think "auch" refers to, and why they would be using "jedoch" if the Fw190 had a better dive acceleration as well as the better dive speed.

 

Small note to Celestiale - dive limit of the Fw190A-2 at the time was 750km/h at low altitudes.

[6./ZG26_5tuka]

The posted report does not name neither the 109s nopr the 190 assumed max speed. The last sentence has to be taken with a great grain of salt and can not be used for any conclusions unitl said condition is clear.

 

The order of the report's note don't have to mean anything. It doesn't say at which speed the dives were initiated and if I had to assume it they probably used same airspeeds for both aircrafts to initiate the dive for better comparison.

 

Sure the 109 was better than the 190 A-2 (I reocmmend reading the last not about the reliability issues of the BMW801C) in this test though this hasn't been questioned. I even sayed so in my previous posts. That does not mean it's the same way in a dive at various dive angles.

[JtD]

OK, but my question remains unanswered - why "auch", why "jedoch"?

[Wulf]

Actually, Gordon and Khazanov state 510 km/h in black and white in two separate locations in their book. If you want to invent a figure that suits your agenda, don't pretend you base it on their book. It's you who is connecting unrelated information in order to arrive at a wrong number, not them.

 

 

 

You calling me a liar JT?

 

On page 124 of their book the authors' state that in June 1942 the M-105 PF powered Yak-1 weighed 6430 lbs/2917 kg (the aircraft weight is significant) without radio equipment and attained maximum speeds of 316 mph/510km/h at sea level and 354mph/571 km/h at 3650 m.

 

They then go on to say that in November 1941 a modified Yak-1 was tested incorporating a range of improvements designed to overcome deficiencies in the existing airframe.    They say that the flying weight of the test aircraft increased to 6468 lbs/2934 kg.  They then say the aircraft's performance was correspondingly reduced.  Maximum speeds for the modified aircraft were found to be 290 mph/ 468 km/h at low alt. and 347 mph/560 km/h at 4800 m.  The authors explicitly state that the speed of the 'modernized' fighter was "7.4 - 10.5 mph/12-17 km/h less than that of the normal Yak."

 

Given the speeds attained by the test aircraft (290 as opposed to 316 mph) we must reasonably conclude that it was fitted with the non-boosted M-105 P motor.   We are told by the authors that in April 1942, 7 Yaks were tested with boosted engines (subsequently designated as M-105 PFs) and these increased level speeds by 12.4-15.5 mph.

 

So, if we accept that the Yaks modeled in the sim have both the boosted motor and the modernized airframe, (and we know they have the modernized airframe because they have a trim tab on the rudder - one of the improvements incorporated in the 'modernized' airframe) we should arrive at pretty accurate (although on the generous side)  level speed for the model by adding 15.5 mph to the low level max speed  attained in the test.  If we do that (290 mph + 15.5 mph) we arrive at a figure of 305.5 mph or 491.6 km/h.

Edited March 10, 2015 by Wulf

[Uriah]

Just did this for my own.

below pulled the first numbers I think from Chuck.

The second number is what I got repeatedly (give or take a 1 or 2.

And what I did was just on NORMAL and just to let me know if I can get away or catch up or not.

 

 

=========LaGG-3===LA-5=====Yak-1====Bf-109f4=Bf_109g2=FW 190-A3

Sea level==505/530==555/540==520/547==545/568==565/558==588/578

Edited March 10, 2015 by Uriah

[303_Kwiatek]

Question is how long you could fly with such speed at which power settings?  F-4 for 1 minute? A-3 for 3 minute?  Yak-1 until burn fuel?

 

More important problem beside too good high alt performance of Yak-1/Lagg-3  and more important then a few kph more in low alts are too high maximum safe dive speeds for all Russian planes.   All could go up to 750 kph IAS without risk of structural damage.

 

Knowing Russian manufacturing problems and other issues im sure that Russian pilots didnt want to go much above restricted dive speeds from manuals.

Edited March 10, 2015 by 303_Kwiatek

[GOAT-ACEOFACES]

Knowing Russian manufacturing problems and other issues im sure that Russian pilots didnt want to go much above restricted dive speeds from manuals.

Knowing German slave labor intentional manufacturing problems and other issues im sure that German pilots didn't want to go much above restricted dive speeds from manuals.

[Uriah]

If young men knew what war was like there would be no wars.

[6./ZG26_5tuka]

Despite it being offtopic I feel this needs to be cleared up.

 

In 1942 slave labours were not employed by aircraft manufactures in germany. That happened way later in 1944-1945 and mostly agains the will of the manufactorers themself. The planes in Stalingrad are 100% factory fresh build models.

 

As for the russian planes it was the other way round. During 1941-1942 their quality was by far the worst. Aimed for quick mass production cheap materials were used and manufacturers refrained from applying upgrades, which pilots had to do in field isntead. Also the aircraft quality differed from each factory. That changed till 1944 when superiour airplanes like the Yak-3 and La-7 hit the stage, which also used more high quality materials and production methods.

 

So yes, the Lagg-3, Yak-1 and La-5 should suffer from structural inconsistency compared to german all metal aircraft. Devs surely don't involve manufactoring errors in BoS but from a construction standpoint the russian fighters should be highly critical at high speed.

 

I think they should improve the consequences of high speed overstress btw. The only thing to fear currently is controllsurfaces ripping off which seems kind of harmless to what real pilots had to face (oscillation, very light/heavy controlls, compressebility, structural collapse of the airframe, ect). Maybe that oculd help to model VVS plane dive speeds more realisticly.

Edited March 12, 2015 by Stab/JG26_5tuka

[[BTEAM]_Shifty_]

If young men knew what war was like there would be no wars.

Young men don't start the wars

 

 

 

That changed till 1944 when superiour airplanes like the Yak-3 and La-7 hit the stage

 I hate discussions about bad quality because it is not relevant in game

But these two planes are examples not of great quality but of great optimization and simplification. You take what you have and you do best possible plane with it.

[6./ZG26_5tuka]

Depending on how you judge it. If Yaks for exmaple had detsinctive restrictions due to overall quality deficit it should be considered ingame. As long as this error did not apply to numberous deployed machines at the front it's indeed not worth being taken in consideration, even less in a more "ideally" modeled sim like BoS.

 

I just mentioned them since they both were much higher quality airplanes than the early Yaks and Laggs. By that time russians began to replace wood with metall and had moer time to imprive their planes as the Luftwaffe began to shrink on the eastern front. Of course manufacturers still aimed for rush production and so the aircrafts have been.

 

Anyway that's offtopic and I agree it's not worth discussing. Just stepped in due to the slave labour argument, which by that time has not been the case in german aircraft factories.

[[SUOMI]Perustaja]

Depending on how you judge it. If Yaks for exmaple had detsinctive restrictions due to overall quality deficit it should be considered ingame. As long as this error did not apply to numberous deployed machines at the front it's indeed not worth being taken in consideration, even less in a more "ideally" modeled sim like BoS.

 

I just mentioned them since they both were much higher quality airplanes than the early Yaks and Laggs. By that time russians began to replace wood with metall and had moer time to imprive their planes as the Luftwaffe began to shrink on the eastern front. Of course manufacturers still aimed for rush production and so the aircrafts have been.

 

Anyway that's offtopic and I agree it's not worth discussing. Just stepped in due to the slave labour argument, which by that time has not been the case in german aircraft factories.

The post was just banter anyway, I think we all agree we don't want reliability and mechanical issues to be implemented in any shape or form.

 

As for the original anecdotal evidence, it's a bit dubious because of the unknowns as stated earlier. Bobbing up and down in a 190 is not a great idea because its climb rate is poor, and you may be losing energy in that bob while the pursuer is staying agile. There is also engine management to take into account, who had the energy advantage before this dive, etc.

 

Seems like a Warthunder post to me.

[GOAT-ACEOFACES]

I hate discussions about bad quality because it is not relevant in game

Agreed 100%

 

Flight Sims have always simulated factory fresh planes..

 

Read best case scenario

 

Not because they could not model failure rates..

 

But, because it is a bad idea to try!

 

If you think the argument of the anecdotal evidence and interpretations of the variations in flight test data is bad..

 

Wait until someone tries to implement a failure rate model to try and take into account silly things like Russian production line errors or German slave labor errors.. 

 

The post was just banter anyway,

Bingo!

 

I think we all agree we don't want reliability and mechanical issues to be implemented in any shape or form.

Agreed 100% Edited March 12, 2015 by ACEOFACES

[Brano]

Every plane coming out of the factory had to undergo final flight tests.And they were strict.Many of them were returned back for rework or completly refused.Materials used for production were of standard quality,not inferior.All tested prior serial production.Institutes like TsAGI,NII VVS and others guaranteed that all specifications are met.There were pretty tough sentences for sabotaging war efforts in USSR.There were of course lots of daily problems in production as in any other industries in the world.Human errors,lack of communications,trained staff,subsuppliers...

Many people confuse "rough/crude" finish of the machine with "it must be a peace of crap and for sure will disintegrate in the air".

[von_Tom]

Just a general comment as I have no idea about the relevant aircraft performance. 

 

My usual tactic is hit and extend.  So, I just attacked a Yak that was going in the opposite direction.  He had a friend who was high off to my left, but slow having just turned away from a He111 that was going down.  My attack was in a shallow dive at 440km/h followed by a little bunt and full power run in a shallow dive, then bunting again when in cloud, down to the deck at full power with trim to stay level.  Took less than 1 minute to be caught.

 

I have no idea if that's right or not.  It's certainly different than pre-patch, and S! to whoever caught me.

 

von Tom

[LukeFF]

Every plane coming out of the factory had to undergo final flight tests.And they were strict.Many of them were returned back for rework or completly refused.Materials used for production were of standard quality,not inferior.All tested prior serial production.Institutes like TsAGI,NII VVS and others guaranteed that all specifications are met.There were pretty tough sentences for sabotaging war efforts in USSR.There were of course lots of daily problems in production as in any other industries in the world.Human errors,lack of communications,trained staff,subsuppliers...

Many people confuse "rough/crude" finish of the machine with "it must be a peace of crap and for sure will disintegrate in the air".

 

Sure, but in many cases early in the war there were a lot of quality control problems with planes coming off the lines that were accepted into service. LaGG-3s seemed to be the worst of the lot. One factory making LaGGs was turning out planes built so poorly that they were described as being only able to make circles after taking off.

[ShamrockOneFive]

Sure, but in many cases early in the war there were a lot of quality control problems with planes coming off the lines that were accepted into service. LaGG-3s seemed to be the worst of the lot. One factory making LaGGs was turning out planes built so poorly that they were described as being only able to make circles after taking off.

There is also the Yak-9 production line that for a while was using cheaper paint that was breaking down the wing materials until they would separate in mid air. Allegedly Yakolev had to answer that one to Stalin himself.

 

There are all of those possibilities in real life that I'd rather not have the devs try and simulate in game.

Edited March 15, 2015 by ShamrockOneFive

[GOAT-ACEOFACES]

There are all of those possibilities in real life that I'd rather not have the devs try and simulate in game.

Bingo!

 

That and the sides that won the war tend to have better documentation of the 'problems'

 

Where as the side that lost the war tended to not have time or resources to test for let alone document all the 'problems' add to that the fact that even if they did, there is a good chance the documents were lost during a fire during a bombing raid.

 

So, I would hate to see the devs try and model failure rates based on documentation.. And in so doing 'feel' they need to make the Russian planes fail more often that German planes simply because more Russian documents survived the war than German documents

 

Stick with the factory fresh simulation IMHO, that is challenging enough wrt documentation.

[LukeFF]

 

 

Stick with the factory fresh simulation IMHO, that is challenging enough wrt documentation.

 

Agreed. I am happy with assuming the plane I am virtually flying in the game has been properly checked out and cleared to fly by the ground crew. 

[Livai]

@ Wulf why you not create a Mission were both planes are 1 km away from each other and you are the one who try to escape. Both planes fly straightforward same altitude. The best way to test the FM. BTW you never reach the full advantage on a Normal Difficult Multiplayer Server because all important things like Radiator... are set automatic. And more important the Engine never warmed up that alone means that the planes fly arcade. Not much but enough.

[Reflected]

I'm no expert of this topic, but I enjoyed reading all your comments and test results. So back on topic: apart from the crazy Vmax and the questionable lack of overheating, is the Yak-1 too fast at low altitudes?

[Original_Uwe]

I'm no expert of this topic, but I enjoyed reading all your comments and test results. So back on topic: apart from the crazy Vmax and the questionable lack of overheating, is the Yak-1 too fast at low altitudes?

Nope.

If operated at safe combat settings within normal temps it only makes 508kph TAS.

Of course if you operate it outside that Im sure you could squeek out a few more kph.

http://forum.il2sturmovik.com/topic/16186-german-fighters-speed-testing-they-seem-pretty-darn-close/