Its probably only at sea level, 190 As lose power VERY fast with altitude.
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Just don’t turn with japanese props. If your attack fails just keep flying, they won’t get you. Then set yourself up for a new attack run. When you start the turning competition you’re dead.
Just follow the iron rule: Do not turnfight vs Jp.
What is an A6M7 bro? are we just making up planes now???
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Straight winged planes have the COP shift forwards on the aerofoil, making them less stable (closer to relaxed stability). An aircraft with proportionately bigger wings (A6M) will experience this effect more strongly. In real life, they reduced input at higher speeds to compensate.
It’s probably why the Zero gains back (relative) SEP near the extreme top end of chart, as she gets closer and closer to relaxed stability.
An artifact of extreme simplifications.
The way it’s useful is; if (for a given fighter) the prop often tries to hit the ground when you brake; the reserve stability is low so it maintains turns very well.
Technically the trend reverses if they go over m0.85 but a Gaijin prop isn’t about to hit transonic unless it’s a P-39.
Kinda technical.
Gaijin’s fake CLmax is very important, since it basically determines how “stable” the plane ends up being.
A plane like G.55, “woe is me” had a fictional CLmax of (god forbid) ~1.5, making it the ultimate UFO in all of WT history. Well of course it was Axis so it was never fixed.
Most gaijinfighters have 1.3, on a good day. 190’s won’t turn since they have fictional CLmax ~1.2.
109E bleeds hard because the CLmax is ~1.23 but the elevator pull is harder.
A less stable plane needs to induce less drag to complete an amount of turn. So G.55 for example, was a definite UFO; itr, str, climb, stall, you name it.
Gaijin’s BR system reflects the fact the average FM is held together with scotch tape.
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I’ve noticed that Japanese planes really suck like you can be prayed on by a bf-109 and a p-400 witch Is so annoying so I think they should be slightly buffed
Main reason is because it stalls to easily
They should be. Japanese planes historically- and in game- have a fair few weaknesses that all opponents, once they realized, exploited relentlessly. J2M, Ki-84, N1K, less so- but especially the early war ones.
Japan is only “OP” because players give up their own advantages and try and turn fight us.
Yes Mr. P-47 Thunderbolt I would like to loopidy loop with you. Oh I’m OP now with my two 12.7’s to your eight, my paper plane to your metal monstrosity?
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Ki-44II,J2M2/M3, and A7M1/2 all been around 200kg lighter than they should have be in real history. They also dive much faster compare with historical manuals, many of those planes were allowed to dive faster than 830kph IAS in current game, while in history, Ki-44 was limited with 650kph IAS, Ki-61 limited 700kph, and Ki-84 750kph, J2Ms were limited to around 400 kts IAS. Only N1K2 was made with correct historical performance, although its fuel tank was made too flammable.
Also the A6Ms are having too light elevator power lost compare it with in history. The value as low as 1.8 was assigned to the A6M5’s elevator, compared with 2.0 on Hellcat and Corsair, 2.5 on the Ki-84 and 3.5 on VL Pyörremyrsky. Considering that the stick force on Zeros were measured to be around 15-25lbs/G, which is a multiple of planes listed with higher elevator compression coefficient. And A6M could pull around 12G in game , that would require around 240 lbs of force exert on the joystick, this can be ridiculous.
Of course, considering that the game tends to use optimal figure to set up a balanced game mode, these may be acceptable.
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Do you have a source for those? Because I was going through a book on the Ki-61 recently and I have not seen a dive speed that low. It was an extremely well-built plane with very permissive dive and G load limits.
Yes, according to the US translated version of the ki-61 flight manual 「キ６１操縦法」, the official dive limit was 700 kph IAS. Unfortunately, it seems both ki-61’s original flight manual and operation manual in Japanese may have been lost, since it does not appear in the market.
You might have seen some Japanese aerospace magazines list ki-61’s dive speed limit to be 850kph, that number is definitely too high, presumably derived from static load data that does not reflect aeroelastic and compressibility that airframe will meet at critical Mach number. As there are even few US aircraft like P-51 and P-47 were hardly allowed to perform a dive at that high speed. The reason was compressibility, the airflow will separate at high speed, causing the aircraft to experience buffet/flutter/stall/control reversal. Some pilot may claim to perform a dive higher than this speed, either they had enough experience to recover from a compressibility dive, or the pitot static tube shows incorrect data at critical mach number ( sometimes off by 100 knots). N1K2 was designed to perform 450 knots IAS dive, but in reality the number was limited back to 400 knots due to unsolved compressibility shock wave issue.
Furthermore, Ki-61 airframe does not show any property to support it to dive at 850kph, yes it has tri-spar design. But don’t forget that ki-43 too used tri-spar and proved to be structurally weak. Ki-61’s airfoil was quite conventional with a quite convex mean chamber line at leading edge (NACA 24000), a large aspect ratio of 7.2 , and with a large aileron span( about 50% of wing span). All of those properties means it will have a quite low critical mach number (airfoil cause early separation), a larger AR ratio results in earlier separation on the wing tip further reducing its critical mach number, and its large ailerons would likely encounter heavy flutter due to aeroelastic effect at this compressibility dive.
The policy of War Thunder on dive speed limit is usually said to be +30kph on the number displayed in official flight manual, thus we see quite low dive speed limit on soviet planes.
Official limits are not absolute limits - they include some safety margin “just in case”
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That was why “+30kph” policy was incorporated for dive speed in War Thunder. All aircraft in other nations follows the policy of manual number + safety margin, clearly the late Japanese planes were not using the same standard, except for N1K1 and K2 that corrected implemented such limit ( 740kph limit + 30kph margin).
My claim comes from the Bunrindo book on the Ki-61, which I’m still slowly going through as translating every single page is tedious. But there are pilot testimonies of them maxing out the airspeedometer (well past 700kph) and obviously living to tell the tale.
As for the various features you mentioned, they can all be found on other piston engined fighters with similar IAS limits. The mach limit for the Ki-61s isn’t impressive.
Unless the rivet counters haven’t gotten to the P-47 and called them unbalanced, the Ki-61 is quite a ways behind it in mach limit. In fact, you’d have to go all the way down to the Wildcat to find a M0.75 limit, with all the other single engine fighters that come after it being able to go at least past M0.8.
Then we can compare it to the Bf 109s:
Here’s an F-4. Single spar wing, yet boasts a higher mach limit and only slightly lower IAS limit. It’s a similar story even with the earlier E-4.
So I doubt that a plane that took very obvious inspiration from a certain european fighter and was remarkably rugged (with its wings tested to 15G equivalent, surviving that with little damage, at which point they stopped testing and moved on) would somehow have both a lower IAS and mach limits.
The Ki-43s were all very lightly built and not as fast, so they’re more exceptions than a rule.
So I doubt that a plane that took very obvious inspiration from a certain european fighter and was remarkably rugged (with its wings tested to 15G equivalent, surviving that with little damage, at which point they stopped testing and moved on) would somehow have both a lower IAS and mach limits.
Static load test does not reflect aeroelastic nor compressibility effect, which is a common since, also “14G” was an optimistic number for ultimate load factor ( real structure failure beyond this limit), without considering real air load and buffet that will encounter in actual flight. That is a consensus in aircraft design. The compressibility effect itself has little to do with the structure, its more of an aerodynamic stuff, and a flutter induced by compressibility has to do with the natural frequency of the structure, it was never to be that you build a plane more rugged and it will dive faster, the aircraft design wasn’t that simple. A rugged aircraft could still meet an early separation of the airflow and been thrown into an uncontrolled compressibility dive.
Here you mentioned the BF-109 dive limit in game to be 790kph, that is a very good example of such “manual + margin” policy. The bf109 has similar airfoil as ki-61, but shorter wing span, smaller ailerons, thus has a faster dive limit than the ki-61. The manual of bf109 limits its dive at 750kph IAS, thus Gaijin gives it 790 with 40kph margin. Although there were a lot of testimonies claimed bf109 experienced dive as fast as 900kph. Again that don’t count, since the pitot static system error in compressibility dive.
Unless the rivet counters haven’t gotten to the P-47 and called them unbalanced, the Ki-61 is quite a ways behind it in mach limit. In fact, you’d have to go all the way down to the Wildcat to find a M0.75 limit, with all the other single engine fighters that come after it being able to go at least past M0.8.
The P-47 was designed to have large dive speed with its Seversky airfoil, and incorporated many compressibility dive tests, later on equipped with recovery flap to obtain a such hight dive speed. Another example would be the F6F-5 in game ,which was limited only with 803kph in a dive, which was slower than ki-61. While in reality its dive limit was 440 knots IAS and some testimonies said it dove at 870kph, the Ki-61 pilots in Kanto air battle found their dive speed couldn’t match the Hellcat.
三式戦
イ旋回性能我と概ね同等若しくは敌やや优る。我が高度差１５００ｍ付近より突进せば、敌の旋回回避により射距离内に入りたるときは追随困难なること多し。
ロ急降下速度は、我よりやや大なり。
The 803kph limit in-game came from the F6F-3’s limit with 415kts due to tail buffeting coupled with natural frequency of the tail. That was another example about dive speed of an aircraft has a very complex nature.
Again, I would say other than this dive limit, ki-61 family was quite accurate in the game. This dive speed issue can be accepted to make Japanese plane in game competitive, but I have to say the reality would be less optimistic.
It looks like this limitations based a just on airspeed indicator which was limited to 700km/h
The same with J2M airspeed limit
And mostly for Ki-84 airspeed limit
So limitations at manuals might be caused by indicators what maximim numbers was less than actual dive speed
Ki-44II was using the same airspeed indicator with Ki-61, while the manual showed 650kph as the limiting airspeed.
The airspeed indicator somewhat reflects the lack of confidence for allowing higher airspeed to be achieved. It could explain why ki-84 switched to indicator with larger range. The same can be explained by the lack of experiments on performing compressibility dive.
The 400knots limit on J2M should be the same, since the N1K2 manual explained that 400 knots limit was set due to compressibility shock wave, thus the targeted 450 knot limit was not achieved.
Ki-44 is also good example at this questions.
It is similar to Bf109 va Ki-61 dive speed. Ki-44 has smaller wing spar than Ki-61 but has lower dive speed what is strange.
The exact coincidence of the dive speed, as well as the speed indicator, may indicate that the dive speed limit was set due to the fact that the pilot could not know higher speeds than the indicator showed.
The problem is that it is similar story to the Bf109 and Ki-61. J2M had much lower wing spar so I really doubt it should has the same dive limit
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