Best fighter in Eastern Front, 1943.

[CORSNING]

OK then, back on track. I read the whole thing but I'm sticking with the P-39. Top of the rugged scale with 1,500 lbs. of Allison rear armor protection for the pilot. Overall speed that when VVS push more than hung in there. Overall maneuverability on vertical/horizontal plane that gave it options and a 37mm blast at short range unequaled. At least at the altitudes involved.

 

[DerAdlerIstGelandet]

Corsning, please use the Edit function from now on. It prevents you from having 3 to 5 posts right after one another. If you realize you forgot something, just hit the edit button and add it in.

 

[CORSNING]

Sorry Adler, I'll give it a try. I'm not the most computer literate.

 

[Altea]

Hello CORSNING, you're welcome

CORSNING
OK then, back on track. I read the whole thing but I'm sticking with the P-39. Top of the rugged scale with 1,500 lbs. of Allison rear armor protection for the pilot. Overall speed that when VVS push more than hung in there. Overall maneuverability on vertical/horizontal plane that gave it options and a 37mm blast at short range unequaled. At least at the altitudes involved.

The engine weight close to plane's CG also improves manoeuvrability, reducing inertia moments as time of respunse on commands.

Once this said, P-39 D was a very good plane for 1942 for the eastern front, but in 1943 it was overpassed by other soviet fighters at low alts.

La-5 reached 562 km/h at SL in may 1942 (530-550 for serial planes). Yak-9 T (T for tyajeli -heavy canon) 533 km/h at SL at nominal (max continious). Not a single P-39 made better than 500 km at SL even at CP 5 min rews, because it had no low alt blower as soviet planes, only one row, one speed blower for 4000m alt.
La-5/5F/5FN had two speed blowers, one optimised for 1650 m on first stage, ~ 5500 for the secund, the Klimov 105PF at 800m, the 105 PF-2 at 0300 m on first stage!

So they were real low-alt fighters, P-39 only a mid alt one.

The Yak-9T had a more powerfull 37mm, with high initial speed that could be used against armor. That was not the P-39's canon case.
Once amnution fired, the P-39 was dangerous to stall with vicious spin, cause aft CG to mean chord.

A good plane, underquated in west, but still not the panacea !

Regards

 

[CORSNING]

Altea,
In 1943 the VVS began using the P-39N. Much improved over the D model and very much comparable to any other aircraft listed on this thread....at least up to around 6,500ms. You are absolutely right in saying others performed much better higher up. But on the subject of the Yak-9T: Performance was down from the standard -9 because of weight of the cannon.

 

[CORSNING]

Altea,
As I stated earlier and posted the USAAF figures, the P-39N with USAAF equipment had a sea level speed of 544km/hr. VVS pilots pulled wing guns and equipment to improve roll, maneuverability and SPEED. I do not have any proof (at this time) as too how far they improved speed. So in my imaginary world I am SWAGing that number at sea level may have been 555-565km/hr. But just an FYI: I have seen the elevation of Moscow listed from 530ft. to 810ft. So once again I'm guessing that not much fighting went on at sea level. Ground level yes.

 

[DonL]

A difference of opinions should always be an enrichment, not an annoyance, but olny with people that have something to say.


That excludes DonL -Bada:

I don't think that you can estimate what I have to say and my knowledge about aviation in WWII!

it would be difficult to them to demonstrate to an educated engeneer how a plane of 4070 (4270)/ 18.3 = 222 kg/m² WL and 4070/1700 2.39 kg/hp Power Loading could deal (on a dogfight) with another of 3290/17.6 = 187 kg/m² WL and only 3290/1850 = 1.78 kg/hp PL!!!
Just to say it's a huge difference, in the world of aeronautics.

First of all, history had proved, that the FW 190A-5 in 1943 was more then an equal match for the La-5FN, or do you have primary sources, which indcate massive losses of the FW 190A-5 in 1943 to the La-5FN. No german Jagdgeschwader had documented that, other then the Jagdgeschwader of Defending of the Reich compare to the Bf 109G with P47, P38 and P51B!

Now to the technology aspekt. If your stated suggestion was right how on earth could a P38 and P47 match with a Bf 109G?
The BF 109G had the much better WL and kg/hp then the two other birds but wasn't automaticly the winner if anything the contrary.
Your statement is wrong!
A dogfight in WWII isn't automatically a turnfight! And acceleration is important but many other things too!
You can't negate this to WL and hp/kg! That are indicators, but nothing more.
Engine altitude performance, dive, controls of a fighter at high speed maneuvers and controls of the engine are other very important indicators!

As the primary sources from Hans-Werner Lerche stated, the La-5FN had problems with high speed maneuvers, cause the forces on control surfaces became excessive. The controls of the engines at different flight attitude were very difficult to handle and the La-5FN had clear disadvantages in dives and at altitudes above 4000m compare to the FW 190A-5!

I'm not pro- or anti- someting or something esle, j'm just saying that comparing planes it's not a matter of taste (i like lemon, not choklate), but physics...

I realy doubt that, I think you have a clear agenda!

 

[Shortround6]

Altea,
As I stated earlier and posted the USAAF figures, the P-39N with USAAF equipment had a sea level speed of 544km/hr. VVS pilots pulled wing guns and equipment to improve roll, maneuverability and SPEED. I do not have any proof (at this time) as too how far they improved speed. So in my imaginary world I am SWAGing that number at sea level may have been 555-565km/hr. But just an FYI: I have seen the elevation of Moscow listed from 530ft. to 810ft. So once again I'm guessing that not much fighting went on at sea level. Ground level yes.

Difference in air density is about 2% per 1000ft. difference between sea level and 700ft is the difference between a low pressure day and a high pressure day. Most performance trials were corrected to a "standard" condition. That is a difference between air pressure on a given day (or altitude of site) or temperature should have been figured into the test results. See some of the take-off and climb charts at World War II Pilot Training Videos Playing Live For Free Over the Internet

for the differences even 20 degrees can make.

There is something strange going on with pulling weight to make a plane go faster. Many sources/stories say increase weight caused many planes to slow down (sometimes a lot) But "America's Hundred Thousand " says that increasing the weight of a P-51 by 1000lb would only slow it down by 3mph. That is with no change in external drag except the increased angle of attack needed for the extra lift. Ditching external gun pods probably does more for drag reduction than just the weight difference. Ditching the internal .30s does get rid of protruding barrels. Holes in leading edge of wing and perhaps the case and link chutes and holes in the bottom of the wing?

It may get to the same point in the end but I think a proper idea of what was actually going on allows for a better analysis.
Lower drag=more speed.
Lower weight= better climb.
There is a bit of cross over of course

 

[michaelmaltby]

When the Soviets first started pulling guns from the Cobra - they were pulling internally mounted 30's. The mix of three types of gun: 37, 50's (all in the nose) with the wing-mounted 30's can't have been the best for a close-in firing solution, IMHO .

Weight-loss aside - the P-39 with just nose armement was best-suited to the Soviet fighterpilots' style.

MM

 

[CORSNING]

A good plane, underquated in west, but still not the panacea !-Altea


Underquated? Not wanted because of low ceiling and short(er) range. This did not apply in Russia front.
Panacea? Of course not, no plane is. BUT the F4U-4 and P-38L came close.
I have just been saying that in Russia in 1943, the P-39N was dependable and had excellent performance. Its the closes thing to the Panacea at that time and place. It was there in spades when it was needed most.

 

[Altea]

The only way loss statistics

many any sense

at all is if they are losses per so many sorties flown.

LA-5 was the second most produced soviet fighter and so, if losses were even, it would have the second highest number of losses in combat. For the period we are talking about if may have been THE most produced soviet fighter and so had the highest losses.


No, it means the methodology of the statistic is bad.

1) What makes sense it's to have statistics first, that's not obviously P-40K-'s case...
2) From my numbers*, one La-5, F, FN, lost every 194 combat missions
For Yaks it was 1:168 at the same period.
On other hand, accident rate was heavier on the La-5's family.

Good post of yours

* A i V magazine from automn 43, to late spring 44, something like that

Regards

 

[Altea]

Thank you but something still isn't right. Many other sources give 376mph at 15,000ft for N and 357mph at 10,000ft using military power. Granted the WEP is 1420hp instead of 1125hp but according to the cube law you need 1564hp to hit 399mph at 10,000ft if I did the math right. 1420hp should get you to 385mph. This is assuming the drag coefficient stays constant.

etc...
.

Hello,

In the absolute you're right... for a train!
The cube law is applied on a plane both for the drag, and lift!
In order to not climb, once pushed to 1420 hp, you will have to reduce the AoA, improving Cd due to induced drag reduction.
I can't say more for the P-39 N without speed polars.
But imagine a current 10 to 1 glide ratio. 90% of the power increase would be converted to lift, 10% to drag!

Anyway, that smelt a manufacturer advertising, as for the 631 km/h instead of 573/578 promissed for british Cobra's ...before the RAE/AFDU tests!

Well, Bell company is far for being the exception in that case!

Regards

PS Elsewere, i trust you in saying that power increase does much for improving turn or climb rate (it's the same thing: a turn is a climb at high-g factor (apparent weight)), few for the speed.

 

[Altea]

Altea,
As I stated earlier and posted the USAAF figures, the P-39N with USAAF equipment had a sea level speed of 544km/hr. VVS pilots pulled wing guns and equipment to improve roll, maneuverability and SPEED. I do not have any proof (at this time) as too how far they improved speed. So in my imaginary world I am SWAGing that number at sea level may have been 555-565km/hr. But just an FYI: I have seen the elevation of Moscow listed from 530ft. to 810ft. So once again I'm guessing that not much fighting went on at sea level. Ground level yes.

Hello

Unfortunatly, no such speeds were revealed nor by soviet LII neither NII tests. Even in manufacturer chart, giving something as 531 at S.L. annd 601 at heignt.
The P-39Q-15 tested in june of 1944 gave this data above.

482 km/h at SL with american or soviet (B-95M ...) 100 oct fuel, at C.P.
468 with soviet 94-95 (B-78 M 3 or 4) fuel mark*.
The rate of turn decreased and it took full 20-21s to complete a sustainted 360° turn

*4Б-78 и 1Б-95 in russian

Higher regimes seemed to not be used, due to some reliability (MTTF, MTBR...) problems.

Regards

PostScriptum: the SL speed is just the prolongation of the curve.
I have made some tests on hanglider polars, some many years ago, never obtained a curve, just clauds of points, i had to smooth by statsistical methods to obtain a curve!
And this with calibrated Ball, Windmaster instruments that WWII pilots even could dream about such a precision/quality.

So all testsof that period (some with political, economical pressure and a lot of arrengements between friends...) may need a cautious approach.

 

[CORSNING]

Altea,
I've seen this graph and several others with the same IDs at the bottom. I even took some (not all) performance figures for the La-5FN from them. BUT, although the Russian government wanted all the P-39 they could get, they frowned on the fact that some of their best aces chose to stay with the P-39 instead of switching to a domestic aircraft. I will look up some examples if I have to.
I chose not to take all the figures for the -5FN climb because these charts had its initial climb listed at 4,337fpm (just a tad bit overrated). Like I said earlier, that is La-7 territory. I'm not saying the Russian
government didn't post the truth. I just don't think they posted all of it.
Now for a few statements by Nikolay Gerasimovitch Golodnikov (Conversations with N. Golodnikov):
You have to keep in mind that these are opinions of Major-General (Ret.) Golodnikov and not highly contained comparison trial.:
"The Cobra, especially the Q-5, took second place to no one, and even surpassed all the German fighters.
The Cobra was not inferior in speed, in acceleration, nor in vertical or horizontal maneuverability. It was a very balanced fighter.
It seems that everything depends on what you wanted out of it. Either you flew it in such a manner as to shoot down Messers (109) and Fokkers (190), or you flew it in a way that guaranteed 120 hrs. of engine life.
The Messer engine had a supercharger. It had exceptional acceleration, if the pilot " firewalled" it. But I couldn't describe its speed as outstanding. It was fast, but our aircraft had just as much speed.
The strong points of the Fw-190: 1. Powerful and high-altitude capable engine. 2. Powerful cannon armament. 3. Good dive characteristics. 4. Light on the controls. 5. Good visibility from the cockpit.
The weak points: Average acceleration. The acceleration dynamic of the fokker was perhaps its weakest characteristic.
The Fokker also was not equal to the Airacobra in the vertical, although they initally attempted to fight with us in the vertical plane. We also quickly broke them of this havit. I still don't understand why they decided that the Fokker could outperform the Airacobra in the vertical."

 

[Altea]

I don't think that you can estimate what I have to say and my knowledge about aviation in WWII!

I never wrote about your knowledge about aviation history, only the low general (technical scientific) level of your posts.

First of all, history had proved, that the FW 190A-5 in 1943 was more then an equal match for the La-5FN, or do you have primary sources, which indcate massive losses of the FW 190A-5 in 1943 to the La-5FN.

Even in global english, if something is proved, it takes a demonstration before. Where is it, have you got the results from all dogfights occurred in 1943 between La-5FN and FW-190A?

The BF 109G had the much better WL and kg/hp then the two other birds but wasn't automaticly the winner if anything the contrary.

Except it was
1) bounced first,
2) surpised,
3) plenty of fuel and ammunition
5) climbing (high AoA, low speed)
6) by several P-47, and P-38s
7) all 3/4 or half empty
8) boom-zooming it from alt
it had really the better chances. Did your ear BTW about total energy conservation principles?

The results of the fights are not undependent from the context and situation!

A dogfight in WWII isn't automatically a turnfight!

By definition, and since WWI the dogfight, or dog fight, is a form of aerial combat between fighter aircraft; in particular, combat of maneuver at short range (close-in high g manoeuvering combat), where each side is aware of the other's presence. Even if it's performed in vertical (loops, immelmans...).

But for sure, not all off WWII aerial combats between fighters were dogfights! There were also energetic fights.

And acceleration is important but man etc...!

And this is 100% clear. What is 100 unclear it's why do you still imagine that FW-190should have a better one?

bis

And I have absolutely no doubt that a FW 190A could outroll and outdive a La-5FN in every situation
Ah yes? Have you got the La-5FN rollrate, and BTW the La-5 FN and FW-190A acceleration?

Engine altitude performance, dive, controls of a fighter at high speed maneuvers and controls of the engine are other very important indicators!

For sure but again:
bis

Originally Posted by DonL
Hell yes, throttles are very unimportant for a fighter and it is total unimportant too, how a fighter reacts to the controls in high speed maneuvers.
Again. So if they are such important, what is the problem with La-5 FN throttle?
Give datas. What are the efforts on commands vs speed on both planes, times of reaction, etc?
Thank you very much for the enlightenment, as you said.

Than means efforts on commands can or may be higher, that does not mean that they were unacceptable!

As the primary sources from Hans-Werner Lerche stated, the La-5FN had problems with high speed maneuvers,

And why should it be a La-FN, not a La-5, or a La-5F?

, I think you have a clear agenda!

1) I'm in better position to know if i have an agenda or not
2) You'v got a lot of things to think about before worrying about that
3) and at least have the politeness to answer to some of my questions!!!

 

[DerAdlerIstGelandet]

And it was only a matter of time...

We never can have a thread that stays peaceful.

 

[bada]

I never wrote about your knowledge about aviation history, only the low general (technical scientific) level of your posts.

Hey altea!

Sorry man, not eveyone can have such a marvelous infinimous aerodynamics internet knowledge as you do

And this is 100% clear. What is 100 unclear it's why do you still imagine that FW-190should have a better one?

for two reasons:
1°: you took the wrong engine output for the la5FN, as it has 1230kw and only available under 2000m
2° check the 190 factory documents about the take off distance and time. You'll see that tha big fat 190 with it's 4000kg took off in the tame time and the same dstance as the spitfire9....what plane has the better acceleration? Not bad for a 1338kw engine
NOTE the power units used here (kw), as the PS and the HP are not the same units....

For sure but again:
bis
Than means efforts on commands can or may be higher, that does not mean that they were unacceptable!

Not for a german combat pilot, it seems.
Several seconds needed when pushing several levers for a full acceleration makes the plane accelerate slower than the one where you only have to push one and where all the settings are directly interpreted by a "mechanical computer". See the NACA test on the kommandogerrät about the reaction times of the mechanism.

And why should it be a La-FN, not a La-5, or a La-5F?

same wooden krap.


If you really want to show your aero knowledge, please go here and simply show your math in the 190 section. Reactions will be fast

 

[parsifal]

Oh Dear.........

 

[Altea]

Hey altea!

Sorry man, not eveyone can have such a marvelous infinimous aerodynamics internet knowledge as you do

Thank you, this is too much, at least for internet.

for two reasons:
1°: you took the wrong engine output for the la5FN, as it has 1230kw and only available under 2000m

I took the 1943 ASh 82 FN, used since march in Lavotchkin fighters.

1850 hp (PS in fact) at 2400 rpm at 1180 mmHg at SL for TO or 10min forsage
1630 at 2400 rpm at 1000 mmHg at 1650m nominal = max continuous.

It takes more than internet wikipedia knowledge sometimes you see to have the right numbers.
1673 hp are mentionned nowhere in soviet charts. 1700 hp (PS) it's for the 1941-1942 M-82/82 F engines at SL at 2500 rpm and 1140 mmHg.

2° check the 190 factory documents about the take off distance and time. You'll see that tha big fat 190 with it's 4000kg took off in the tame time and the same dstance as the spitfire9....what plane has the better acceleration? Not bad for a 1338kw engine

1338 kw with 990 mmHp boost? I doubt so
Soviet trials on benchtest gave 1600 PS at 2700 rpm at 990mmHg fot TO. But it was for a 1942's engine.
Maybe more in 1943: 1700 PS i guess, like it was written on engine plates, no more...
At least 1700 are also from derman docs, no?

NOTE the power units used here (kw), as the PS and the HP are not the same units....

I now but 1 to 0.986 does not makes a huge difference

Not for a german combat pilot, it seems.

For a russian, french or tchecoslovakian it seems stangely to be ok.
They were probably not handling the same Lavochkin plane...

Several seconds needed when pushing several levers for a full acceleration makes the plane accelerate slower than the one where you only have to push one and where all the settings are directly interpreted by a "mechanical computer". See the NACA test on the kommandogerrät about the reaction times of the mechanism.

Explain again, what several levers for the La-5?

same wooden krap.

As the DH Mosquito?

If you really want to show your aero knowledge, please go here and simply show your math in the 190 section. Reactions will be fast

And they will explain me how a 522l FW 190 has three times range of 539l La-5?

DonL, so, i'll go for an A5 anytime, triple flight time, "intelligent" flight commands,

BTW,why they do not come here to show their brilliant knowledge?

 

[Tante Ju]

German BMW 801D-2 engine had output of 1800 HP (continental horse power - PS) after 1,42 ata clearance. This is for ground level output, static output.. 1730 etc PS listed - dynamic output. So BMW was very powerful engine in 1943. Expert says this clearing occured late 1942. Probably more in 1944 - 2000-2100 PS with injection.

Also to consider - response of engine to throttle. Direct injection engine had good throttle response, so power available quicker. Its only real power that accelerates. Take off on other hand is not very good measure of accelerate - it is effected, but, there is also other factor. Like flap etc.