Oh, so the RPM base is lowered AND there are stops for the propeller.
Yes
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Ye I agree with that. 400 RPM would be the lowest possible.
One thing to note is that Japan used 30% safety margin for the mechanically synchronized nose cannons.
Ki-43-I with its 2 blade props would have higher rate. Ki-43-II & Ki-43-III would be having a lower fire rate due to the 3 blade props. Ki-84 would be the lowest firing with its Ho-103.
One thing about them is that the nose mounted army cannons use HE, so they had to put extra measures, like the engine armor on Ki-61-I tei.
What is considered is that Ho-103 in this game has the constant 900RPM regardless of the installation, no way it’s right. And the whopping 950 RPM for Ho-5, literally double that of nose mounted Ho-5 in 4 bladed configuration.
By using Logitech G hub. I recently tried modelling the correct fire rate for the guns. By putting 10 milliseconds push-pull delay and a variable span between the cycle.
Ki-43-I with 700RPM, Ki-43-II with 600RPM, Ki-84 with 400RPM seemed reasonable to me. Though it’s based on my broad guessing.
Type 97 7.7mm machine guns on naval aircraft are also stated to have a rate of around 600 - 700RPM.
Despite the non-constant fire rate, having that much variance on the fire rate means it’s actually affected by the propeller’s condition more than the inconsistency. Firing 1000 rounds and the luck would be almost certainly negated, so the cause for that 100RPM difference is the props. Not specifically the number of the blades but the revolution per minute.
About P-39, yeah it’s a total exception from any other installation methods.
I read somewhere that prototype hurricane used hydro… what is that, sonic pulse thing…? To sync the guns. That’s pretty cool. Mg151 and Mg131 have the Electrical primer for the ammo, and most other guns of German heritage used Electric signals to time the firing. So they are less affected by the mechanical delay per shot. That’s why Mg131 still has the high fire rate in the cowl mounted configuration, and MG 151 is able to be fired through propellers even though they are mounted in the wing roots. This is to just inform the players visiting here, not trying to correct anyone. I think having these things modelled in this game would be pretty cool. Though the gun firing sounds are specific to that fire rate of the guns and they can’t really be optimized for different fire rate, since all the “Loop” audio files are in the length of that specific time span between each firing. M4 37mm cannons and alike use singular file for both single fire and automatic, and these sounds play fine in automatic firing, so all guns with variable fire rate can be formatted that way. If they are to make a change, that is.
Japanese 50 cals and 20mm utilize HE rounds of high filler contents, so that even for 50 cals they needed extra safety margin with the already aging mechanical synchronization system. That’s what I’m guessing as the explanation for such low fire rate in the nose.
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Aw shucks, it’s really weird that others can’t see the pre-edited post. I just changed the line “can’t optimized” to “can’t be optimized” since that’s the correct way of saying things. That’s all.
There seems to be a misconception about the Ho-103 HE rounds, so I will share the information here.
The following three types of HE bullets were used in the Ho-103
- Italian-made HE rounds
- Ma-102 (made in Japan, without fuse)
- Ma-103 (made in Japan, with fuse)
Ma 103 was already in production in 1941 and Ma 102 in 1942. Therefore, it is almost certainly incorrect to say that Ma 102 was put into service in 1944.
Incidentally, the Ma 103 seems to have changed from a mechanical fuse to an air fuse around 1944, so there is a strong possibility that you are confusing that information.
The Ma 102 has 2.70 g of explosive and 1.05 g of incendiary.
The Ma 103 has 0.5 g of explosive and 1.0 g of incendiary.
Both are based on primary Japanese sources.
postscript
There seems to have been a translation error, which has been corrected.
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Currently, WT’s Ho-103 has the following three types of ammunition
AP (made in Italy)
AP-T (made in Japan)
Ma-102 (made in Japan)
Not a mistake, but an interesting combination.
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Ah, that explain it. I was wondering where that AP came from.
Forgot about the Italian AP.
These are the actual explosive weights and not TNTe, yes? What type of explosive did they use, if you happen to know?
Ma-102 is 50:50 PETN/RDX and Ma-103 is RDX.
I could not find any Japanese documents, perhaps they were disposed of, but they are clear from the U.S. military survey data.
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Ah yes, a slow Japanese plane that can turn real good should be higher. As someone else said, “have you tried not fighting a Japanese fighter?”
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The Ki-44 isn’t particular slow. It’s in fact faster than a large portion of 3.7 planes.
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Just played this stock to spaded. the FM is generally wonky, I had to fight its roll and you can easily over-roll if you even do some slight rudder. Some shots that I could’ve done on other planes are hard to do on this thing because of its weird roll-rudder tendencies.
Overheats fast so MEC is needed, the 12.7mm’s somehow rip to planes more than the f#@%king 20mm’s of the germans. Engine power drops off at 4.1km though, not that bad but it still has some oomph to it at 5km. It’s easily 4.3 material. I guess the only thing holding it back in Gaijin’s eyes is the armament and how newbies tend to play it.
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Actually doesn’t turn that well, a 109 E-4 could beat it in a dogfight. But it’s pretty nice.
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I know only two things about Jap planes (not American ones with a red circle): they are slow and they can turn.
There was speculation on whether Ma-102 was actually put into service. The round was said prone to self-detonate and was restricted from being fired when the barrel temp was above 200 degrees C. Seeing so many Ma-102 in the Air Targets belts just looks weird.
The WarThunder does tend to give some weight figure just for displaying, for example the weight of the aircraft MG that you can see in the X-ray mode, which wasn’t actually used in aircraft weight definition, and neither was the necessary property in the weapon definition. There seems to be a weight breakdown definition in the blkx FM file for every aircraft. Yes, these lines are in ki-44hei.blkx seems to be a little weird. The pilot only weighs 17kg instead of 90kg in other aircraft, the engine mass of 600kg does not match the listed 720kg Ha-109. Perhaps the real weight was defined from these lines?
Adding up all values, this gives me an empty weight for ki-44hei 1840kg instead of 2090kg listed. I checked other FM file and this mass breakdown should sum up to equal to the empty weight. If this is true, then Ki-44 is indeed 300kg lighter in game.
However there is also a property AdvancedMass, which is turned off for the ki-44. Could this variable decide whether the game uses pre-defined empty mass figure, or the mass breakdown figure?
They produced a ton of Ma-102 and someone posted a Japanese ammo belt configuration containing it.
The round is heat sensitive but not that much.
The round is fired at just around 800m/s compared to US .50cal M23, which was particular plagued from self-ignition, being fired at over 1000m/s.
In a synchronized gun the RoF would also be lower than the AN/M2.
Which actually made me wonder why they had both Ma-102 and Ma-103.
My guess was that the Ma-103 was used when the gun was likely to overheat, for example in wing or flexible mounts, where the RoF was substantially higher.
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There is no doubt that the Ma-102 was used in actual warfare.
However, it is true that there was a fear of self-destruction at temperatures above 200°C.
According to the documents in my possession, it is written that the use of bullets above 150°C is prohibited, and it seems that Ma-103 was used after the number of bullets that reached 150°C or higher.
(The specific number of bullets is unknown.)
For reference, it says that “Ma-101” (IAI) included in 7.7mm also self-destructs as well, so after 150 rounds, Ball was used instead of Ma-101.
Up to 150 rounds: AP, Ma-101, I
After 150 rounds: AP, Ball, I
(the T is not included because the I actually served a tracer function)
Related Reports
https://community.gaijin.net/issues/p/warthunder/i/UzZkoYN22gBW
https://community.gaijin.net/issues/p/warthunder/i/TkLvnmrqHqPZ
Source
- 佐山二郎, 「日本陸軍航空武器」, 光人社NF文庫, 2021-1-24
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I haven’t heard that before. Samples of all 12.7mm rounds were captured and examined before war ended. At least one book also lists the usual recommended belt loadout. It was practically the same for all IJA aircraft guns: Special Incendiary / HE / AP-T. Sometimes AP-T was supplemented or replaced with HE-T if such excisted for the specific gun.
“Rough estimate”, but this is likely the best there is. Likely the demand was to produce equal amount of those four rounds. Not the faintest idea why snail dropped the fuzed HE round from Ho-103.
Average weight of a 110cm (5’4"). That’s obviously the early test of anime girl pilot models. About high time for them to start selling those.
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Thanks, I heard that they may put ma-102 at the start of the sequence, and then ma-103, looks like a true story.