Vympel R-73 'ARCHER' - History, Design, Performance & Discussion

It was a misread on my end. Don’t pay attention to those numbers

I know, but why u write this me? I wrote about the discrepancy between the data and the message in the post and in the brochure.

Ahhh sorry I’ve replied to the wrong post oops.

It says, the guidance time us 38s, a launch range of 50km would mean the average speed is likely around 900m/s at high altitude/max range, that’s accounting for a 35km travel range, it’s possibly even less.

Yup, as I said in a post above, I misread it, just took the 20 seconds from the previous r-74 battery life. with 38 seconds that makes a lot more sense

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I should really have read this thread before posting ahah, I blame gaijin for making threads open to the last place you were ahaah.

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The R-74M2 has a better engine than the R-73.

No worries!
Btw, 2500 should be read as " Maximum speed of engageable targets - 2500 km/h"

do you have anything of its real range? 30, 40, 50km are just nuts

Any news on ASRAAM?

What missile are you speaking about?

You should ask this in the British weapon thread on here

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R-73 and R-74M2

The guy i replied commented about ASRAAM

r-73 max range is 30 km

Spoiler

r-74m2 max range is 50 km

Spoiler

also what do you mean by “real range”

I managed to fix tvc missiles spinning out of contol. They also now pull more consistently at different speeds and don’t waste an insane amount of energy for less pull than an aim9l like they to right now in game.

Spoiler

https://youtu.be/jw6xZJGj0z0
https://youtu.be/9G0ulkDfc9E
https://youtu.be/C0EsFR_BLuA
https://youtu.be/o5DJWRyfd5Y

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Ok, so what did you change

Was messing around in test drives of diffrent vehicles when i noticed that kh23m missiles on the yak 38 auto rotate after launch so i was curious and checked what kind of guidance do they use and what made them rotate (“rollStabilization:b = true” is the line). But the interesting line was the one right under drag that i have not seen on any other missile before. That line is CyMaxAoA:r = 1.8. So i just copy pasted it into r73s and they started to work (and changing 1.8 to 40).

An important thing to note this does NOT fix r73s and missiles alike on its own.

Spoiler

To understand that you have to understand what causes the missile to spin out and what max aoa under guidanceAutopilot does. When missiles in war thunder reach 90° aoa (or rather their lead point) the guidance seems to break (why is that i have no idea). Gaijin tried to fix this on r73 by giving at a 40° aoa limit. But the problem is that all of the code under guidanceAutopilot are not hard limits but more of a… well guidance. This means that the missile will try to lead untill it reaches its max aoa and than stop. The problem is that its inertia will cause it to go over that point (again because everything under guidanceAutopilot is not a limit but a guidance (this is also why magic 2 can pull 50g)) wich results in a death wobble and ends with the missile spinning out. So what happens when we give it CyMaxAoA:r = 40 that works more like an aerodynamic “hard” limit and delete the guidanceAutopilot “soft” limit on its guidance? The missile stops spinning out in 9/10 shots. So how do we fix that and give it a 100% success rate? The reason the missile will still spin out in extreme shots is because while it is now aerodynamicly “hard” limited to 40° aoa its guidance is not. This resulst in the missile attempting to lead more even after it has reached the 40° aerodynamic “hard” limit. By keeping both the guidance limit of 40° AND this new aerodynamic limit of 40° the missiles stop spinning out.

Now as far as I can remember r73 is the only tvc missile in game that has a known aoa limit of 40 (correct me if i’m wrong). Thats why when you try to fix other tvc missiles that don’t have one the easiest and most successful method i have found is giving them CyMaxAoA:r = 180 but with no max guidance aoa. For the most part this works but some kind of guidance aoa should porb be applied as well.

TLDR: R73 in game has a guidance limit but no aerodynamic limit which causes them to spin out. Applying this “new” line (CyMaxAoA:r = 180) fixes it.

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With this change you can now also increase the tvc angle form 4,05° to something like 12° with no issues. This is especially important since small tvc angles have no impact on the missiles turning ability at higher speeds which means r73s rely on its fin aoa at speed to turn and its tvc has no impact (wich is why micas and r77 turn the same when you fly at speed but not at 0 speed launches (its also why rolands are so hard to fix))

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