The P40 thread

[BlitzPig_EL]

Landing and moving on the taxiway is better as well.

 

It's nice to have the hawk back.

 

[chris455]

Landing and moving on the taxiway is better as well.

 

It's nice to have the hawk back.

 

El,

Are there still discrepancies in your opinion or are we "there" with this release?

Have always regarded you as the "P-40 guy" on the various forums .

[ShamrockOneFive]

I'm sure the guys are going to want to test it out a bunch but I can say without a doubt that the P-40 is 100% more enjoyable to fly in 2.012 than at any point previously. Engine limits are still an issue but the actual handling and flying of the aircraft seems to be more in line with what I'd expect from the P-40. You can handle it without side slipping into a nasty stall immediately and it seems to fly and hold its energy better than before.

 

I've got more flying to do but it appears that the P-40 is back!

[Venturi]

OK. I've had time to do some preliminary tests. The results are in:

 

The P-40 is BACK.

 

We can talk about some of the "hard numbers" engine parameters still. Perhaps when more advanced modelling of detonation is implemented, we will see further improvements on this front for the P-40. It would also be a very important aspect of the pilot experience, which all aircraft and users would greatly benefit from -- similar to the 2.012 FM update. In any case, I do feel that the acceleration of the P-40 has increased somehow by tweaking the engine operating procedure I use, but just can't put a finger on why yet. 

 

The most important thing I can say, is that the Warhawk now flies like a fighter ought to! It dives well, it turns well at high speed, and it can maintain a good turn with no fear of spinning, even at low speeds and tight turns. It rolls very well at all speeds, and has good control authority at low speeds especially, but maintains that control authority to 400mph and beyond in a dive. In other words, it is a different aircraft.

 

The downside, well it is a P-40, so it doesn't climb very well. It doesn't do anything higher than 15,000ft well. Those are attributes it should have.

 

It is not a world beater, which it should not be! I only had time to test the 109F-2 for comparison, and would take it as the better pure fighter in most instances. But, it now feels like a capable 1941 fighter, and I would give it at least 50-50 odds in a 1v1 contest with the 109E-7. Obviously they are both very different aircraft. This is a VAST change from previously!

 

Overall, I am very pleased. Part of why I am pleased is that from my limited experiences tonight, I get the feeling that the FMs have now been looked at and standardized in some way across the board. Which was desperately needed. This great work by the FM team has made huge strides for the product - not to mention all the other cool stuff in the update. Devs, PLEASE maintain this approach to FMs in the future! Remember how important the Core Mechanics are to this sim! Be brave!

 

I would now recommend the P-40 for purchase. Before this update, based on the purely ahistorical performance of the FM, I would have said "you will be upset and will not fly it". But after the new FM, I can confidently say the P-40 is now a fun Pursuit Plane to fly, and if you are a fan of P-40s, it is a good product.

 

A few minor technical bug notes from my limited time tonight in these two planes:

 

1. The P-40 still does not have animated bomb switches (although the panel has the cutouts for them). It is a real shame to not model "bomb arming" and "bombs on/off" switches, when the switch cut outs and placards are already there on the dash! It is a premium plane after all. The engine overheat light should come on when the engine gets hot. 

 

2. It may simply be a missing or corrupted file, but the Bf109F-2 has a missing bolt graphic in the front windscreen frame.

 

 

Well done, devs! Next up, engines!

 

 

Edited August 30, 2017 by Venturi

[BlitzPig_EL]

What he said.

 

 

In the two non combat flights I made last night I finally felt like I was in a fighter plane, not a lumbering municipal bus.

 

The controls all worked in harmony and I could fly the Hawk pretty much without thinking about it, except for the engine limits of course, but using the rudder normally was now without fear of slipping on the proverbial banana peel.

 

The improved energy retention does indeed make a difference.   Before, even just keeping a steady cruise speed took a lot of effort and concentration, now running 250mph IAS seems so much easier, with less fiddling with throttle/prop and trim all the time.

 

Hopefully tonight I'll try some combats against aircraft, and ground attack as well.

[[CPT]Pike*HarryM]

Sank an e-boat with the 50s, fun!

[Cybermat47]

Nice to hear that the Eagle of New Guinea is being treated right at last

[Venturi]

Sank an e-boat with the 50s, fun!

 

The guns are impressive. 50cal BMGs are beasts.

 

https://www.youtube.com/embed/sTYGDVrZQPI?start=28

 

https://youtu.be/ldqQx6bc3QE?t=14s

 

https://youtu.be/niJ82YCiuYU?t=50s

 

https://youtu.be/oO3gE7VA0Hs?t=17s (2 guns only)

Edited August 30, 2017 by Venturi

[VBF-12_Stele]

I flew in 3 one on one dogfights (109s and 190s) last night in WOL with the P-40. Managed to win two of those fights. She is a beast in bed at 12k ft now! I was impressed with the handling in low and high speeds. She was able to keep up in vertical and horizontal scissors, and does well in a dive chase. It definitely wasn't Yak handling, but it is a huge difference than from the previous updates. I fly the P-40 almost exclusively and it feels like the ankle weights just came off.

[LLv24_Zami]

I`m glad for you P-40 guys that it got a little extra attention in this FM improvement. It was necessary and it feels quite good now. Devs did pretty good imo! I think I´ll fly some campaign missions with it now, never really bothered with it before apart from some ground attack missions. 

Edited August 31, 2017 by Zami

[Tag777]

Great improvement. Still, the engine issue remains. Hope a fix be possible.

[BlitzPig_Bill_Kelso]

The P40 is borked.

 

The FM is waay over modeled now.

 

Dev's , please dial back the P-40!

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[Venturi]

It does still stall at 95mph.

I`m glad for you P-40 guys that it got a little extra attention in this FM improvement. It was necessary and it feels quite good now. Devs did pretty good imo! 

 

I also think so. More importantly, even though it is not perfect, it fits into the right place amongst the "lexicon" of airplanes in the sim. 

[unreasonable]

The Spitfire Vb in game stalls at a minimum of 85mph - compared to 73mph IAS as per the Pilots' Notes.  (F+G up).

 

The devs are being consistent, at least in the case of these two.  I do not think the Tech Specs have been fully updated yet since the stall angle of attack is still shown as 14 degrees, and IIRC the update notes mention that it had been increased.

 

I am in complete agreement that the most important thing is if it fits correctly into the range - also glad that now Russians, Germans, Italians, Britons and now Americans can all fly in at least one plane of their nation that makes sense, should they be in a patriotic mood!

[Venturi]

I flew in 3 one on one dogfights (109s and 190s) last night in WOL with the P-40. Managed to win two of those fights. She is a beast in bed at 12k ft now! I was impressed with the handling in low and high speeds. She was able to keep up in vertical and horizontal scissors, and does well in a dive chase. It definitely wasn't Yak handling, but it is a huge difference than from the previous updates. I fly the P-40 almost exclusively and it feels like the ankle weights just came off.

 

I will say that in an entirely equal one v one duel, with equally capable pilots... P-40E against a 109F4, G2, or G4 - you will most definitely lose in the P-40E. The 109s have more power on tap, for longer. If the P-40's engine were to be given historical limits, then I suggest that most pilots who fly 109s in the manner usually seen, would not be safe at anything below 12-13,000ft. There is an argument to be made that this could very well be historically correct, considering that almost all accounts of LW pilots who fought against the P-40 did so in the traditional "vertical" attack method. As per official LW instructions to its fighter pilots in the African theatre.

[Tag777]

Well I found this book. Is the Allison Operation and Maintenance Handbook for the engines of p-38, p-40 D/E and p-51 A. There I highlighted the page for F3R engine (p-40 D/E) at War Emergency Rating (1470 HP. 3000 RPM, 56" Hg manifold pressure). According to this, you can stay with the engine in that condition for 5 minutes at sea level. I am not sure if 56" Hg corresponds to engine at full power (that in game usually means the point where the engine die almost instantaneously).

Edited August 31, 2017 by Tag777

[216th_Lucas_From_Hell]

That is correct, however the section on using WEP is pretty restrictive as well and it goes on to specify the conditions required for using it.

[Venturi]

The current MP gauge in the P-40 is of the old type, and is correct for an early P-40E. That is, it only goes to 50" MP. This is similar to the gauge in the P-40B and C, (V1710-33, more fragile "long nose" Allison variant) and with the P-40D which was identical to the E model in most ways. That being said, later variants of P-40s came equipped with MP gauges to 75". I would argue that the interior of the P-40 needs a little looking at anyways (bomb switches, coolant temp light).

 

The later Allison uprating of the V-1710-39 occurred after the US 100/130 octane fuel had the "color" dye removed from it. This dye was added for ground crews to be able to immediately determine what octane fuel it was, regardless of can markings. The major problem here, and it is relevant to the sim, was that this dye additive caused backfires with the Allison engines, necessitating backfire screens to be placed in the intake manifold (refer to Vees for Victory, pg 118). These caused a pressure drop across the screen. And backfires continued to occur with this fuel, anyways - and could even disintegrate the screens, causing engine damage and failure. Later, this logistical error was cleared up and the backfire screens could be minimized or removed (these are the "Streamline manifolds" mentioned in the ratings sheet). The engine itself was not at fault. The problem with everything in this situation was with the logistical whims of a bureaucracy which did not understand the technical aspects... paradoxically causing larger and even more extreme technical and logistical problems. Pilot training also mattered. Quick throttle-backs would induce backfires as well, which were WORSE with the screens in place.

 

The increased power ratings you mention, also occurred after Allison had had enough time to observe the engines under combat conditions to understand they were being overly-conservative with the earlier, lower MP ratings. Also, after enough time and combat experiences with the Japanese aircraft had taught the US Army (who promulgated such information to the pilots) that a slightly shorter TBO time was less important than pilot and airframe survival. As it is, you can see in Hazen's letter this discussion occurring, especially concerning the V-1710-39, and his acquiescence that even up to 60" MP was tolerable, as compared to "extreme" usage.

 

The issue is that people conflate logistical glitches and administrative conservatism with the equipment's technical abilities. When the former two had been sorted, the Allison proved that it was not only better than the equivalent Merlin at altitudes below 14,000' or so, but that it did so for longer, was simpler, and could take more abuse. The fact that the US Army insisted on turbocharging and did not develop supercharging (while Rolls-Royce did), only shows that American engineering and manufacturing abilities can always be compromised by poor leadership. "The Americans always do the right thing.... after they have tried everything else."

Edited August 31, 2017 by Venturi

[Venturi]

Well I found this book. Is the Allison Operation and Maintenance Handbook.

 

Yes, it was published in April 1943. In the old engine thread, it was shown that the manifold pressure regulator was supposed to be retrofitted under a Technical Order sometime before this printing (in 1943), which went along with the Allison uprating to 56"/3000rpm. The only issue is, that by this point the P-40E was no longer being made, and so the technical order only applied to aircraft already operating in the field (IE, deep south Pacific, or Mediterranean), or those who entered service at some restoration depot. You may imagine that this was not carried out thoroughly on a fighter which was by now, not new. The other issue is that pilots widely disliked the automatic pressure regulator, because it prevented them from overboosting the engine. Mustang I crews in the British RAF (which aircraft came with an Allison engine with this device already mounted on it), actually actively removed said regulator in the field, to give the pilot the ability to overboost the engines.

 

The whole issue here, is that the equipment was capable and was actually, designed, for 1500hp from the outset of the introduction of the F3R/-39 engine. That is, it was designed for 56"Hg manifold pressure and 3000rpm, which gives nearly 1500hp. That is the structural strength limit of the engine, and that is where it should enter "danger" territory - in addition to the detonation parameters given by the fuel octane rating (over 60" manifold pressure).

 

The intake backfire screen issue was largely resolved by the middle of 1942 (July 1942, Allison petitioned Army to remove additive, and was successful, Vees for Victory, pg 118.)

 

EDIT- that should be pg 116, above.

Edited September 5, 2017 by Venturi

[CIA_Yankee_]

So, as I understand this, the P-40 is in a better position now, being able to fly like an actual fighter and not a brick that falls from the sky the moment you try and turn. But it remains hampered by unrealistic and exaggerated engine limitations?

[Jade_Monkey]

So, as I understand this, the P-40 is in a better position now, being able to fly like an actual fighter and not a brick that falls from the sky the moment you try and turn. But it remains hampered by unrealistic and exaggerated engine limitations?

Same engine, no changes there.

[Tag777]

Yes, it was published in April 1943. In the old engine thread, it was shown that the manifold pressure regulator was supposed to be retrofitted under a Technical Order sometime before this printing (in 1943), which went along with the Allison uprating to 56"/3000rpm. The only issue is, that by this point the P-40E was no longer being made, and so the technical order only applied to aircraft already operating in the field (IE, deep south Pacific, or Mediterranean), or those who entered service at some restoration depot. You may imagine that this was not carried out thoroughly on a fighter which was by now, not new. The other issue is that pilots widely disliked the automatic pressure regulator, because it prevented them from overboosting the engine. Mustang I crews in the British RAF (which aircraft came with an Allison engine with this device already mounted on it), actually actively removed said regulator in the field, to give the pilot the ability to overboost the engines.

 

The whole issue here, is that the equipment was capable and was actually, designed, for 1500hp from the outset of the introduction of the F3R/-39 engine. That is, it was designed for 56"Hg manifold pressure and 3000rpm, which gives nearly 1500hp. That is the structural strength limit of the engine, and that is where it should enter "danger" territory - in addition to the detonation parameters given by the fuel octane rating (over 60" manifold pressure).

 

The intake backfire screen issue was largely resolved by the middle of 1942 (July 1942, Allison petitioned Army to remove additive, and was successful, Vees for Victory, pg 118.)

Very, very interesting information. I was not aware of the dye issue, for example. Many thanks to you, sir !! 

[Custard]

But it remains hampered by unrealistic and exaggerated engine limitations?

 

I wouldn't use quite such an extreme description, it does not feel hampered in any way whatsoever. Continuous power with the occasional burst of combat power is easily enough to maneuver the aircraft confidently.

[Guest deleted@83466]

I wouldn't use quite such an extreme description, it does not feel hampered in any way whatsoever. Continuous power with the occasional burst of combat power is easily enough to maneuver the aircraft confidently.

 

The engine's durability is still not in line with lots of historical accounts.  I think if the developers simply added a few more minutes to the time it takes to burn the engine out at combat power and takeoff power (now 5 min and 2 min, respectively)  it would bring it more in line with historical anecdotes of being able to push the engine far beyond overly conservative "book" values.  Maybe if it took 8 or 9 minutes to blow the engine at a high power setting, instead of 4 or 5, this would put the issue to bed.  The plane would still be a rather mediocre fighter, as it was considered historically, it just wouldn't be quite as likely to kill itself so soon.

[Venturi]

So, as I understand this, the P-40 is in a better position now, being able to fly like an actual fighter and not a brick that falls from the sky the moment you try and turn. But it remains hampered by unrealistic and exaggerated engine limitations?

 

I would say that the P-40 is now a worthy addition to IL2, if you are a fan of the aircraft.

 

The engine limits are under debate.

 

The original interpretation by the devs of engine limits, was that "all aircraft" have engine failure after exceeding the manual's limits for time in each engine mode. The issue with this, is that some aircraft have far more realistic limits as written in the manual, than others. 

 

The Germans had been using the Db60x series engines in combat since 1938, they knew what the engines were capable of and how to value them in the whole sphere of TBO vs pilot life.

 

The Americans had not yet entered the fray in earnest, when the limits proposed in the 1942 P-40E1 manual (which are in game) had been written. These limits were therefore not tempered with combat experience, and were designed to maintain a long Time Before Overhaul (TBO). Later, after combat experience had been gained, these limits were increased to correspond to the manufacturer-designed capacity of the engine (1500hp). The additional wrinkle in this story is the fuel dye additive (fixed July 1942) and backfire screens, as listed above. However, in optimal situations (clean screen, new engine), these did not significantly affect the maximum MP (power) the engine was mechanically capable of at regimes below critical altitude. And as the devs have stated, their overall philosophy is that every aircraft and engine in the sim, is a new aircraft and/or engine when the pilot enters it.

Edited September 1, 2017 by Venturi

[Farky]

The current MP gauge in the P-40 is of the old type, and is correct for an early P-40E. That is, it only goes to 50" MP. This is similar to the gauge in the P-40B and C, (V1710-33, more fragile "long nose" Allison variant) and with the P-40D which was identical to the E model in most ways. That being said, later variants of P-40s came equipped with MP gauges to 75".

 

 

Later P-40 variants were indeed equipped with MAP gauges to 75 inches, however P-40Es (including P-40E-1s) were never produced with those gauges. They were retrofitted in some airplanes later, but having them in our P-40E-1 would not be historically correct.

 

 

The later Allison uprating of the V-1710-39 occurred after the US 100/130 octane fuel had the "color" dye removed from it.

 

 

This isn't correct. V-1710-39 was approved for War Emergency Rating on 100/125 Grade fuel and dye wasn't removed from US fuel during WWII.

 

 

Yes, it was published in April 1943. In the old engine thread, it was shown that the manifold pressure regulator was supposed to be retrofitted under a Technical Order sometime before this printing (in 1943), which went along with the Allison uprating to 56"/3000rpm.

 

 

I disagree. Technical order for instalation of automatic MAP regulator into P-40E/E-1 was issued in autumn 1943, months after Allison publication. At that time, P-40Es were already withdrawn from combat units. P-40E/E-1 with automatic MAP regulator never saw combat.

[Venturi]

Later P-40 variants were indeed equipped with MAP gauges to 75 inches, however P-40Es (including P-40E-1s) were never produced with those gauges. They were retrofitted in some airplanes later, but having them in our P-40E-1 would not be historically correct. Does not mean the engine could not produce the MP - as you well know.

 

This isn't correct. V-1710-39 was approved for War Emergency Rating on 100/125 Grade fuel and dye wasn't removed from US fuel during WWII. I was waiting for you to help clarify - yes, the dye formula was changed. The OFFENDING dye was removed. The reason why it was done is as I say. Note Hazen reference letter in May 1942.

 

I disagree. Technical order for instalation of automatic MAP regulator into P-40E/E-1 was issued in autumn 1943, months after Allison publication. At that time, P-40Es were already withdrawn from combat units. P-40E/E-1 with automatic MAP regulator never saw combat. Do you have the technical order showing the date? I seem to be unable to find it, currently. In any case, my point remains.

Edited September 1, 2017 by Venturi

[216th_Lucas_From_Hell]

A minor tidbit, a handful of P-40E-1 (as Farky pointed out, from the original RAF order) fought over Kuban from March into the summer of 1943 with 45 IAP, 84-A IAP, and one or two Black Sea Fleet regiments. Navy, air defence and army inits in the north, specifically Leningrad and Murmansk regions, also soldiered some P-40E airframes into 1943. Not relevant to the discussion of course since all aircraft delivered in 1942 and most of 1943 were from 1941 and 1942 batches.

 

Many units took modern versions of the Hawk into 1945. One regiment that participated in the Berlin offensive was flying P-40s, in fact!

[Venturi]

It was one of the few airframes which flew from beginning of the war to the end. It was also flown almost everywhere that the Allies operated fighter aircraft. It was calculated somewhere (lost in all the musings over the information I have done over years), that if the P-40 had a high-altitude engine roughly equivalent to the Spitfire IX, that it would have been capable of nearly 400mph.

 

EDIT - here you go... 420mph with a cleaned up airframe, high-altitude Allison, and wingtips chopped (same airfoil): https://oldmachinepress.com/2015/08/18/curtiss-xp-40q/ 

 

 

So the basic P-40E airframe was pretty clean.Here is a graph depicting what I mean - comparing, roughly, the P-40F (Merlin V-1650-1, single stage, 2-speed, 1300hp), P-39D (Allison), and P-51A (Allison) airplanes.

 

 

So the engine outputs at maximum power (10,000ft or so) are similar. The graph shows that the airframe WAS NOT a dog. It simply was underpowered due to inconsistent and incorrect engine ratings.... (of course, the P-39 was better...)

 

The logical aspect I am trying to raise here, is that many of the, I presume, future American engines... many of which are Allison V-1710s, along with the Radial engines of the F4F, etc.. do not have automatic engine controls. Therefore, they were quite mechanically capable of going "beyond" rated limits at lower altitudes. If this is not addressed in some systematic way, then the future modelling of these engines will also be suspect.

 

The issue at hand here, is how do you model engine failure? Do you use the manual as a hard-and-fast rulebook - if so, how do you account for the paradox that is created when the early-war manuals are overconservative, and there was the pilot ability to actually go beyond "official ratings"? Especially when the historical record states this was done successfully. And doubly especially when later ratings were revised, without real significant changes in the engine.

Edited September 1, 2017 by Venturi

[216th_Lucas_From_Hell]

In an ideal scenario (and I have a sneaking suspicion the developers will get there eventually) you have the resistance of each engine to aggressive use modelled individually in some way. How to get about establishing that is tricky though.

[LukeFF]

My apologies if this chart has already been posted before. The one line I am trying to understand is the one about "100% rated power for 20 min. - balance of mission at 75%." Rated Power - max continuous, combat, or something else?

 

P-40E Specifications and Performance.PDF

Edited September 2, 2017 by LukeFF

[Farky]

Do you have the technical order showing the date?

 

 

I have date of issue of this T.O. somewhere, but I don't wanna dig through a pile of papers today.

 

 

The one line I am trying to understand is the one about "100% rated power for 20 min. - balance of mission at 75%." Rated Power - max continuous, combat, or something else?

 

 

100% Rated Power = Normal Rated Power = Max. Continuous (1000 BHP)

75% Rated Power = Maximum Cruising (750 BHP)

[Max_Damage]

The engine's durability is still not in line with lots of historical accounts.  I think if the developers simply added a few more minutes to the time it takes to burn the engine out at combat power and takeoff power (now 5 min and 2 min, respectively)  it would bring it more in line with historical anecdotes of being able to push the engine far beyond overly conservative "book" values.  Maybe if it took 8 or 9 minutes to blow the engine at a high power setting, instead of 4 or 5, this would put the issue to bed.  The plane would still be a rather mediocre fighter, as it was considered historically, it just wouldn't be quite as likely to kill itself so soon.

Your suggestions include a bunch of IFs and WOULDs plus a big deal of bias. Hopefully the devs will stay away from doing anything like that and treating the p40 specially.

Edited September 2, 2017 by Max_Damage

[Guest deleted@83466]

Your suggestions include a bunch of IFs and WOULDs plus a big deal of bias. Hopefully the devs will stay away from doing anything like that and treating the p40 specially.

 

I guess you must have missed the first 14 pages of this thread. 

[LukeFF]

100% Rated Power = Normal Rated Power = Max. Continuous (1000 BHP)

75% Rated Power = Maximum Cruising (750 BHP)

 

Thanks!

[Max_Damage]

Wow this plane is so good. I am amazed by the firepower it is fun x 10.

[indiaciki]

I flew her yesterday night at WOL. She's still as agile as a Stuka with retractable gear and has the worst engine ever built :D

 

 

Cut my own engine (pressing E by accident while trying to find my key for the outlet cowl), got attacked from behind and crashlanded in a village "Tom Hardy style"

Edited September 2, 2017 by indiaciki

[deleted@31403]

Just starting to fly the P-40. I have read through this whole post. Question about engine damage. My coolant and oil never overheated. I was in level flight about 9,000 feet, non combat. I open and closed my shutters to keep temps good and I get a engine damage. Is the manifold pressure running high long, but temps are good can cause a engine damage. I thought as long as temps are good no engine damage.

What am I missing.

[216th_Lucas_From_Hell]

That only works in game for nominal modes. In combat, take-off or emergency modes the engine automatically sustains damage after the time limit is exceeded.

[Venturi]

And you only need 5% radiator at max continuous power straight and level flying, (in the summer no less), to keep her cool.

 

Should be at least 30-40% radiator.

 

Cockpit needs bomb switches put in, and coolant temp light working.