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The P40 thread

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Well, so now I know why there was a P-40 chosen, rather than P-39 or Hurricane - http://forum.il2sturmovik.ru/topic/417-kakoj-lend-liznyj-samolet-zhdete-v-igre/  http://forum.il2sturmovik.com/topic/745-poll-what-soviet-lend-lease-fighter-are-you-looking-forward/

There were a big polls long long time ago, even before BoS was released asking about preferred Lend-Lease aircraft. I suppose they based on the result chose a P-40, which btw. is just a lovely aircraft  ;)

So thats one proof that devs actually care about our opinions :)

Edited by =LD=Hiromachi

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So what are the selling points of this plane, besides it being the grunt to spit's butterfly and Bf's stallion (Not a bad start, I love workhorse types)? 

 

Sky is not a limit... more like first step.

 

http://en.wikipedia.org/wiki/Aleph_number

The RL P-40 wasn't one plane, but many. Versions B through N varied widely. I would call it a "War Horse" rather than a "grunt". Biggest issues were the lack of a 2-stage supercharger which limited performance sharply above 12,000 ft., and lateral instability which was never completely solved because no one could agree on what caused it.

 

Down low the P-40 was a very good performer. Roll-rate and turn were considered very good. As someone stated earlier, British squadrons late in the MTO were able to more than hold their own against the Luftwaffe at low and medium altitudes. In the ground attack role it was better than either the 109 or the Spit, and could probably take more damage than either.

 

And yes- Oleg's version was no more than a notion of P-40. It would be unwise to base one's opinions of it on that modeling.

 

Let's see what 777 come up with. There is plenty of extant performance data on most models. I'm optimistic, and frankly, it was the deciding factor on my pre-ordering BoM.

Edited by chris455

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I believe most fighter pilots, in an ACM scenario, would opt for roll rate over acceleration, because the roll is the segue to most ACM maneuvers. The P-40 had an exceptionally good rate of roll. As far as acceleration is concerned, altitude permitting, the fastest way to acclerate is to dive. And the P-40 had very few peers in this aspect as well.

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Yeah, but to dive you need to trade some altitude. And to trade it ... first you need to climb to it. And to climb anywhere it takes time. For a P-40 it takes a lot of time. Something like 1570 fpm on take-off, 1630 fpm at 10,000 feet and 870 fpm at 20,000 feet is not much. 

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Yeah, but to dive you need to trade some altitude. And to trade it ... first you need to climb to it. And to climb anywhere it takes time. For a P-40 it takes a lot of time. Something like 1570 fpm on take-off, 1630 fpm at 10,000 feet and 870 fpm at 20,000 feet is not much. 

Point taken, but irrelevant if you're already at altitude, which in most cases other than a scramble scenario, you already are.

Meeting engagements were rarely on the deck- even on Ostfront. There usually 2K-3K IIRC.

 

I have often wondered why the P-39 was the VVS sweetheart, and not the P-40. Both had good radios, cockpits were glazed with same material, had almost identical engines.

 

Maybe Russians liked that big 37mm in the nose? I would LOVE to know how they kept that gun running.

The Americans never figured out how to keep it from jamming after a few rounds............of course, we replaced nearly all of our P-39s with other types as quickly as possible.

Edited by chris455

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Nice Art!  Cant wait for the aircraft of BOM. 

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With the P-40 turning up in CloD and BoM this year, then maybe we should call 2015 'The Year of the P-40' :)

 

It's planned for release in DCS as well this year. However, in DCS it will be expected to fight the only 3 German planes currently in: the Bf-109K4, Fw-190D9 and MiG-29G. :lol:

 

In BoS/BoM, I think the P-40 will be one of my primary planes. The climb rate will be lackluster, but it isn't nearly as bad as Hiromachi claims. And it should be fairly nimble as the plane has a very low wing loading, low stall speed and a pretty good roll rate. Combine that with what will likely be among the best air to air firepower in BoS/BoM, and I think it will do very well in the right hands. Of course, we won't really know how it will do until we have it.

 

Test reports here: http://www.wwiiaircraftperformance.org/P-40/P-40.html

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Meeting engagements were rarely on the deck- even on Ostfront. There usually 2K-3K IIRC.

In real life. In game most of the time 109s engage from altitudes like 5.5 km.

 

 

 

I have often wondered why the P-39 was the VVS sweetheart, and not the P-40. Both had good radios, cockpits were glazed with same material, had almost identical engines.

Because P-39 unlike P-40 could take a vertical fight and follow 109s in loops and other maneuvers like that. P-40 was not suited for that, if you would read any of the memoirs of VVS pilots than those who had opportunity to fly avoided vertical maneuvers. Why ? Because of terrible rate of climb which was a direct consequence of poor powerloading. 

 

 

 

The climb rate will be lackluster, but it isn't nearly as bad as Hiromachi claims.

I dont claim. I simply quote this :

c1kCX2.png

It's not a test in sterile conditions, but the test of the aircraft that was shipped to Great Britain (and same stuff was with P-40s shipped to Soviet Union),  put out of boxes and assembled. Then it was tested to estimate the actual performance. So this is not a performance of some test aircraft but performance of same aircraft that would be flown in the following days against enemy.

 

Dont take me wrong, P-40 E-1 is not a bad airplane. It has some advantages but also has disadvantages. We will see how it will perform in game :)

Edited by =LD=Hiromachi
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It's not a test in sterile conditions, but the test of the aircraft that was shipped to Australia (and same stuff was with P-40s shipped to Soviet Union),  put out of boxes and assembled. Then it was tested to estimate the actual performance. So this is not a performance of some test aircraft but performance of same aircraft that would be flown in the following days against enemy.

 

 

This is test of the aircraft that was shipped to Great Britain, not Australia. It is important to realize that the RAF had somewhat conservative MAP limits for V-1710-39 at their Kittyhawk I. RAAF also tested the P-40E, and the results vary. 

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Ah yes, you are right. It's RAF, not RAAF. My mistake, indeed. 

 

 

 

RAAF also tested the P-40E, and the results vary.

Yes, there is that 75th RAAF Squadron test  in Townsville, 

With a climb time to altitude of 10,000 feet  at 2600 RPM and 37.2"Hg. 

 

And couple of comparative charts. 

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Your source is using a P-40E at far below full rated power. Standard climb power is 3000 RPM and and 43.9 HG, not 2600 RPM and 37 HG. That's why it shows it so terrible. When using factory recommended settings, the P-40E has a climb rate of about 2600 ft/min, not 1600 ft/min. Still not great admittedly, but a whole hell of a lot better than you're claiming. I've already linked the source, but here's a direct link to the PDF: http://www.wwiiaircraftperformance.org/P-40/P-40E_40-384_PHQ-M-19-1300-A.pdf

Edited by King_Hrothgar

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Yes, there is that 75th RAAF Squadron test  in Townsville, 

With a climb time to altitude of 10,000 feet  at 2600 RPM and 37.2"Hg. 

 

And couple of comparative charts. 

 

... and especially CSIR Test No.F.8 - Trials with an 83 gallon Belly Fuel Tank (Kittyhawk A29-129). Initial rate of climb 2000 ft. per min. up to 9500 ft at Rated power ( 2600 RPM/ 39 inHgA), time of climb to 10 000 ft - 5 minutes. 

 

------------

 

For King_Hrothgar - http://www.wwiiaircraftperformance.org/P-40/P-40E_40-384_PHQ-M-19-1300-A.pdf do not use Standard climb power ("Rated power", "Max continuous power"), but Military Power ("All out rating", "Emergency rating"). Just saying.

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Yep, I can read that. It's stated : "propeller set for 3000 RPM for first 5 min. with throttle open to 43.9"Hg manifold pressure (...)" 

When the 5 minutes were exceeded the revolutions were reduced back to 2600 RPM. So the test was executed initially on Military Power. 

W2LGJR.png

 

I know that Allison could run on much higher manifold pressure than 43.9"Hg, the question is if that was possible in Soviet Union and if that was actually done by pilots. But I guess the only ones who can answer that are Russians :)

 

 

... and especially CSIR Test No.F.8 - Trials with an 83 gallon Belly Fuel Tank (Kittyhawk A29-129). Initial rate of climb 2000 ft. per min. up to 9500 ft at Rated power ( 2600 RPM/ 39 inHgA), time of climb to 10 000 ft - 5 minutes. 

 

------------

 

Yes, but the 83 gallons is like 67 % of fuel (or something about that, if I recall full internal fuel capacity was about 120 Gallons or a bit more).

Anyway, thats also a valid point as I dont know anyone running BoS with maximum internal fuel capacity :) 

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Yes, but the 83 gallons is like 67 % of fuel (or something about that, if I recall full internal fuel capacity was about 120 Gallons or a bit more).

Anyway, thats also a valid point as I dont know anyone running BoS with maximum internal fuel capacity :)

 

They do not use only 83 gallons, they tests plywood Belly Fuel Tank with capacity of 83 gallons. Trial were made with and without this Belly Tank. Without tank, the all - up weight was 8626 lbs. Note weight of Kittyhawk AK 572 in RAF climb trials - 8480 lbs. 

 

I know that Allison could run on much higher manifold pressure than 43.9"Hg, the question is if that was possible in Soviet Union and if that was actually done by pilots.

 

 

As I wrote earlier, it was possible always. So technically yes, it was possible in Soviet Union. I see no reason why it would not work, if soviet units equipped with P-40 were using 100 octane fuel. Same engine was later officially cleared for Max power 56 inHgA without changes in construction.

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Yes. And for example, P-40E was tested at TsAGI with such a fuel.

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Interesting. I mean I would expect TsAGI to have such fuel, but on daily basis in combat units ... introducing yet another type of fuel could cause some logistical problems. But if they managed to provide a high octane gasoline for P-40 then it wasn't such a deal. 

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Ooooh chart wars. Nearly as good as the real thing (gets biscuits)...

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Ooooh chart wars. Nearly as good as the real thing (gets biscuits)...

haha.... my thoughts exactly....

 

blah blah blah blah blah.....blah blah blah....... blah ..........blah blah blah blah blahblah blah blah blah blahblah blah blah blah blah....blah blah................... blah blah blahblah blah blah blah blah

 

meh

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I know many here have seen this before, but some may have not.

 

It's a letter from Allison documenting the use of very high boost pressures in the V 1710 used in P 40s, and their angst over doing it...  :biggrin:

 

Allison%201710-39%20abuse.pdf

 

Seems that 60 to 70 inches of manifold was used more than some would think.

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The letter is very interesting - it says that V-1710-39 gave 1570 HP at 60" MP and 3000 RPM, and that those engines were rated for WEP at those values. This would give P-40E a power loading of 0.19 HP/lb, and Bf-109 F-4 would get around 0.21... Most interesting, I'd say (the caveat being that this rating (or higher) would be achievable for P-40 only at sea level, and its high alt performance would be lacking...)

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That's really what it comes down to. The P-40 was an excellent fighter below 3km, it's above that height that it suffered. And it will certainly be interesting to see how BoM models the engine limits on it. The initial manuals were incredibly conservative and quickly disregarded in combat.

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The initial manuals were incredibly conservative and quickly disregarded in combat.

They could also be conservative because designer simply did not expect such high MP to be applied. And for the official RAAF manuals it was more of a matter of preserving the engine and airframe. Americans could share some of P-40s but Curtiss did not have unlimited numbers of airframes :)

 

I dont have any performance expectations. I'm more looking for a nice aircraft to fly and hope that I will spend hours in it.  

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The letter is very interesting - it says that V-1710-39 gave 1570 HP at 60" MP and 3000 RPM, and that those engines were rated for WEP at those values. This would give P-40E a power loading of 0.19 HP/lb, and Bf-109 F-4 would get around 0.21... Most interesting, I'd say (the caveat being that this rating (or higher) would be achievable for P-40 only at sea level, and its high alt performance would be lacking...)

 

Regardless of what the letter says, V-1710-39 (-F3R) has not been rated 60 inHgA for WER, but "only" 56 inHgA (60 inHgA was WER of F4R engine). F3R and F4R (V-1710-73) were very similar engines (performance was exactly the same), but F4R had a little bit stronger constuction (that's reason for higher WER of F4R).

In terms of performance (manifold pressure) vs. height - V-1710-39 was able to archieve 70 inHgA/ 3000 RPM at sea level, 60 inHgA/ 3000 RPM at 2500 ft., 56 inHgA/ 3000 RPM at 4200 ft. and 44.6 inHgA/ 3000 RPM at 11 700 ft. Not quite definite values however, depends on ram (and few other things, like backfire screens).

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As the P 40 had direct aswell as indirect proppitch setting, I hope both get featured in the sim.

 

:salute:

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I don't think the Curitss Electric Propellor has ever been properly modeled in a combat flight sim, this would be enough to push me over the edge and buy the thing.

  • Upvote 1

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As far as I know, it has only been properly modeled in A2A's MFSX Addon of their P40.

 

This kind of details could lead more people to BoS/BoM.

 

:salute:

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P40 coming to early access in September? Yee haaaa!

 

28-p40.jpg

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The RL P-40 wasn't one plane, but many. Versions B through N varied widely. I would call it a "War Horse" rather than a "grunt". Biggest issues were the lack of a 2-stage supercharger which limited performance sharply above 12,000 ft., and lateral instability which was never completely solved because no one could agree on what caused it.

 

Down low the P-40 was a very good performer. Roll-rate and turn were considered very good. As someone stated earlier, British squadrons late in the MTO were able to more than hold their own against the Luftwaffe at low and medium altitudes. In the ground attack role it was better than either the 109 or the Spit, and could probably take more damage than either.

 

And yes- Oleg's version was no more than a notion of P-40. It would be unwise to base one's opinions of it on that modeling.

 

Let's see what 777 come up with. There is plenty of extant performance data on most models. I'm optimistic, and frankly, it was the deciding factor on my pre-ordering BoM.

 

 

Yeah, I suspect you'd probably be well advised to keep your performance expectations heavily sedated when the P 40 comes out.

 

There are WW 2 graphs in existence  (well, certainly one that I'm aware of) that compare the roll rate of the FW 190 with a range of western fighter types; including the P 40.  From memory, that testing indicates that the P 40 rolled significantly less quickly than the German fighter. 

 

Now, given that the in-game Soviet machines appear to roll almost as quickly as the 190 and in one case, even faster than the 190, :)  the poor old P 40 is really going to look shabby isn't it. I'm afraid the P 40 will probably be the slowest rolling aircraft in the game - and by some considerable margin.  

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I suspect the roll rate of the P-40 will be no worse than the Bf 109, propably even slightly better, which means that the P-40 won't be completely left behind in that regard.  

 

The killer for the P-40 is going to be its abysmal climb performance. The P-40E is listed as having a sustained climb of 11m/s, which propably means, that the early versions of the IL-2 will outclimb the P-40 (Late production IL-2 type 3M are listed as having a climb rate of 10,4 m/s, but those were considerable heavier and more sluggish than the earlier incarnations of the IL-2)

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I suspect the roll rate of the P-40 will be no worse than the Bf 109, propably even slightly better, which means that the P-40 won't be completely left behind in that regard.  

 

The killer for the P-40 is going to be its abysmal climb performance. The P-40E is listed as having a sustained climb of 11m/s, which propably means, that the early versions of the IL-2 will outclimb the P-40 (Late production IL-2 type 3M are listed as having a climb rate of 10,4 m/s, but those were considerable heavier and more sluggish than the earlier incarnations of the IL-2)

 

 

Well, I think the P 40 is less quick than a standard Spitfire with wingtips, up to about 400kph (and considerably slower than a clipped Spit right across the spectrum).  So if the Bf 109 is considered to roll a bit quicker than an un-clipped Spit, (and that's what the reports tell us) then I still believe the P 40 will have to be the slowest roller in the game. 

Edited by Wulf

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I don't have the numbers right now, but I don't think you're correct about this. Especially the early marks of the Spitfire rolled fairly poorly AFAIK.

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Finkeren is correct.

 

Early Hawk 81s had roll rates of 130 odd deg/sec.   Even the later heavier Hawk 87s never rolled less than 90 deg/sec.  Any P40 could out roll any Spitfire. and the Hawk 81 could out turn the Spit below 15,000ft.

 

The P40's performance deficit is it's climb rate.   So, the smart P40 pilot will grab altitude in friendly territory before thinking about going offensive.  Once at altitude it gives you the option of BnZ attacks, and can twist and turn down low if necessary.   As a fighter bomber it will excel.   All predicated of course on how the dev team models it.

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Still, in the rolling department, everything in BoM is gonna look bad compared to the Polikarpovs 230 deg/sec  :o:

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That graph shows it average. What's more interesting is you linked to a "flight model" debate on the World of War Planes forums.

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