The R-77 'ADDER' - History, Design, Performance & Discussion

Machinery of War Discussion Aircraft
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Your results aren’t worth shit because the drag value is arbitrary. Like ingame the CxK values range from 1-3 and there’s no clear correlation as to why. The TEMP has a lower drag value than other sparrows. R-23, R-24, and R-27ER are all over the place. There’s no grid-finned missile ingame, so it’s impossible to make an actually appropriate guess at what the drag ought to be. You’ve just grabbed a CxK, got results you like, and biased your way into thinking that’s good.

I gave you a way to try modifying the missile file, and you ignored it. If you want “a number” then maybe if we compare Microsoft Word - Draft-Final-Signed.doc (dtic.mil) and /tardir/tiffs/a384590.tiff (dtic.mil) we can take a stab, the AMRAAM model had a peak parasitic cd0 of 0.45 and the grid fin missile 0.69. So proportionately we might guess that increasing the CxK by a factor of 1.53 might be an appropriate correction, which would give something like 3-3.5 CxK That is really just a WAG though.

We know it’s a hot target because the bugged target has a vector indicator. And like, even for a slow target the time of flight to 50-60km is quite long. I very much doubt that a target clearly above the horizon would be going much slower than Mach .8 or so, given how valuable speed is for BVR. Again, you see something that disagrees with you and dismiss it. And yet you were not so discerning when presented with evidence that supported your preconceptions.

100km is an arbitrary number. I’d believe it if the missile was thrown by an aircraft at a high enough altitude and speed(like a Mig-31 or something), a command/active missile’s range isn’t capped by seeker limits. Now what I don’t believe is that the missile has more than a slight advantage over the AIM-120A/B(I do think that it’s credible that the R-77 has some advantage in a very hot/high shot). In an ordinary BVR shot, that is not doing too much more than Mach 1 or at extreme altitudes, no, I don’t think more than 100km.

Well, if you didn’t want to be attacked about your character, maybe it would have been smart not to do so many things that put it in question. Also double standard much? You have had no compunctions about attacking the character of anyone else.

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Your opinion is arbitrary. My drag coefficient used is based on facts. The missile diameter is the same as the AIM-7F. The drag coefficients in-game are pretty linear and affected by more than just the number. They are affected by caliber.

The R-77 has slightly smaller diameter irl, and the same in-game (200mm). Lower drag wings, and the point of contention is on the grid fins. Using the same coefficient as the AIM-7F is actually quite conservative imo. If you think otherwise we can probably math it out once the CFD is done by the DCS devs. Until then, I’m inclined to believe that the drag coefficient I used netted a conservative analysis of the data.

Heck, I can even test the missile with the obscenely higher R-23R drag coefficient of 2.55 (vs 2.3 for AIM-7F and 2.1 for R-24R). I’ll even test it at an arbitrarily huge number like 2.75.

Iteration 1 test, 2.3 drag coefficient (75km in ~79s) Direct impact.
Iteration 2 test, 2.55 drag coefficient (75km in ~80s) Direct impact.
Iteration 3 test, 2.75 drag coefficient (75km in ~80s) Direct impact.
Iteration 4 test, 3.0 drag coefficient (75km in ~80s) Direct impact.

Seems that Gaijin models very little drag at altitudes of 15km (crazy, I know). Could be other issues with the testing though if there is an issue. I saw the edit to your last post about the CxK and I can do further testing with 3-3.5 CxK though I really doubt it could be that high as the average would be lower due to the reduced drag during periods above mach 2 in comparison.

Also, a reminder that I have yet to adjust the thrust to account for the reduction in drag during burn time. Do you have a recommendation for how much the motor would reduce drag during burn time so I can adjust the thrust?

-edit- I have added the 3.0 drag coefficient test.

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I wouldnt pay much attention to the head on ranges given they are for slower launch speeds and arent a max range, for example the R-27R is given a head on range of 60km, but the R-27 user manual gives the R-27R a maximum range of 90km (which is at a very high altitude and launch speed)

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Facts? What facts? I see a whole lot of supposition and very little in terms of actual facts. For that matter CxK isn’t the only parameter that needs looking at- you could note that there’s also max Fin AoA, wing area mult, max lat accel. I don’t think there’s any clarity at all to how these values impact performance or what they ought to be set to.

Also I like how you’ve realized that having such widely varying coefficients have almost no impact on range is highly suspicious and suggests that there’s something being missed, but proceed to just dismiss it as drag being ignorable at 15km. Like air density is 1/6th that of sea level at 15km, which is less but that drag coefficient has no impact at a point where the air is still reasonably dense makes me suspect there’s some major error here. Particularly given that obviously the missile slows down a great deal from its peak speeds given the overall flight time.

If you want to do a sanity check, make the CxK like 30 or 100 or something and see what happens.

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Honestly I think this whole “max range” debate is pointless

compared to the AIM-120A/B and early C’s the R-77 is very similar kinematically, and the only time youre gonna notice the difference in range is at very high altitude and speeds which in war thunder you just arent doing, 90% of the engagements you will find yourself in you wont notice the range difference they will likely both feel similar to Sparrows rangewise. So this whole debate is pretty pointless youre all basically discussing pedantics

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As a side note, since the primary drag discussion is still around the fins, I feel the base drag is being forgotten.

I’m trying to aquire a book regarding base drag, as its not as simple as other types of drag, but if we take base bleed shells as an estimate, they are said to have an increase in range anywhere between 20-50% over non-basebleed counterparts, and base bleed shells produce no thrust.

As I can’t figure out how long the small gas generator on the back of a basebleed shell lasts, there could be a whole slew of scenarios we could assume from that;

  1. Basebleed gas lasts until target (20-50% range increase, 2 tests to get an approximate range)
  2. Basebleed gas lasts until for an unspecified period of the flight(20-50% range increase, 2 tests to get an approximate range)
  3. 50% range increase obtained from basebleed lasting until target while 20% is from basebleed gas lasting an unspecified amount of the total flight time (reduce drag by 50% during motor burn. I dont like this theory since a shells drag is something like 60% from the air against the shells nose/body, so it doesnt really make sense, but could be tested)

Another assumption that could be used would just be by compairing how much the AIM-7F’s motor overperforms, since we know the AIM-7-E2 is performing according to documentation and both have the same drag.

7F boost stage (4.5 sec) overperforms by ~5.3%
Post boost weight is too high by 13.9%
7F sustain stage (11 sec) overperforms by a whopping ~40%
Post sustain weight is too high by 25%
7F booster burns for 1.7 sec more than the E-2
7F sustainer burns for 11 seconds more than the E-2

Now, I’m sure I could sit down and try to figure out the calculation to figure out the absolute fuckery that is the gaijin AIM-7F to determine an approximate impact of base drag, but even then, it may not help us 100% since base drag is also dependent on shape of the base, shape and size of the fins, speed, etc…

I dont really feel like doing it, but its my input on base drag until I either decide to actually make a CFD for the missiles, or get my hands on papers regarding the impact of thrust on base drag and actually decide to slog through it for an internet argument to try to disprove one specific guy that will likely still find some stupid way to spin the info he gets from reading tea leaves to determine that hes right all along and every air to air missile developper, and every official piece of documentation on the R-77 thats publicly available is wrong.

Now that I’ve thought it over, im definitly not going to put that effort in because he’ll just dream up some other source or draw something on a napkin with some google translate russian writting and use that as his next source to “prove” the R-77 range is over 100km

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Can you site wherein you think the stages are overperforming or have too high weight, etc?

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“I’ve bent sources meanings” when you perpetuate that the AIM-120 exceeding the range of the AIM-7F is anything more than not having seeker range limitations.

Still hurt about the AIM-9L… lol no. That was internally reported by the Tech Mods with the (then current) information on the missile. When further information was discovered that showed it had better resistance than what is shown in-game, it was also passed along in a subsequent bug report (by me). There is no bias here.

Russia doesn’t know how to make a decent jet or missile, that’s evident. What they do have isn’t sub-par though. That’s a lot of conjecture… I’ll have you know I’ve buffed a number of American equipment as well. Bug reporting is entertaining, I like reading about this stuff. It’s not some effort to buff Russian equipment. Look at the F-14 FM, I got that fixed. I am working on the F-16 and Mirage 2000 flight models (both of which should net some buffs). I put in reports for a number of equipment and the primary reason I focus on Russia is because it is foreign, and therefore more exciting to learn / read about.

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Would anyone be so kind as to help me decipher what this would correlate to in the in-game drag coefficient values?

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You have to understand that your fixation with russian equipment. As well as your perceived belief that they are superior has done massive, and lasting reputational damage.

Your group of likeminded people are the reason the F-16s FM is so awkard even to today, by enforcing the “G-limiter” in a game where structural limitations themselves consistently push well past reality.

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Rather my attempts at fixing NATO equipment have been thwarted for whatever reason, and particularly when they are American when other equipment (particularly French) gets special attention when both encounter the same problem.

I’ve put in many reports for American equipment that was underperforming. A lot of the time, Gaijin holds off on fixing some of these (namely the AIM-54C, and AIM-9L) as they might actually be decent if they did.

Other examples include fixing the guidance delay on R-27R, and the overperformance of the AIM-7F that led to the adjustment of missile drag during maneuvers for all missiles in the game.

Not to mention nerfing engine temps (increasing them) on Russian aircraft to make sure they maintain the same standard across the board of using the temp gauges in the cockpit for engine temperatures.

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Oh, an extra little bit of comparative info thats interesting:

The russians apparently did make a surface launched RVV-AE at one point with a range of 12km but it failed. Probably because other Russian surface to air missiles exceed 12km ranges, so it wasnt seen as too interesting for buyers…

The RIM-7M is stated to have a 26km range and its differences are navalizations, not kinematic.

Not 100% sure about this info tho, as its mostly froma cursory search on the internet and not from straight documentation, but is an interesting avenue to look into regarding this whole argument imo…

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There were proposed surface launched RVV-AE models but they had extended booster sizes and iirc never really entered service. RVV-AE-ZRK or something.

If there are models of the RVV-AE that are unchanged and surface launched that would be very very good insight into the performance of the missile.

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Imma be real none of what you said is really true, or taken out of context. I dont know if you have personal beef with the dude or not but dont bring it into here.

his estimates have never even gotten close to doubling the 120As range even the 120C-5 doesnt do that which you just drew a comparison to.

he hasnt provided any fake data just secondary sources that are fairly credible as far as secondary sources go

The AIM-9L thing was just an FOV change to make it correct, the fact the 9L is underperforming right now is something that affects all IR missiles not just the AIM-9L

I dont believe one player actually has the power to make the changes you want either so I dont see the concerns, if one player did have that power then they would have very credible primary sources to back their claim and at that point its true then innit

also bringing mained nations into this is such a degrading argument at this point just say “well X plays X nation therefore anything they say about X nation is biased” into any argument anyone makes

“MiG-29’s voodoo witchcraft flight model” have you seen the F-16A at low speed? or the F-14s cobraing? all these things go both ways.

I dont really get much into these sort of things but from an outsiders point of view I think the lot of you are being unfair and debating purely on bad faith at this point

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Your name alone does damage to your reputation, more so you are aware of Gaijins fundamental, if not institutional, preference for Russian vehicles. Something that has permeated every game mode and vehicle class, for years.

You are conscious that when you post a change for a Russian vehicle there is a much higher likelihood of it being implemented whereas any other nation in the game will experience comedically long delays for correction. You were aware of this when the F-16s first iteration FM performed so well I beat you 10-0 in duels. And yet you proceeded with your bug reports nerfing not only the F-16 to the verge of unplayability but also the AIM-9L to that on a 9J/P, Magic 1.

No one cares about bug reports that go nowhere, they care about what affects their game experience, and you have been responsible for a noticable change in that. That is why you are consistently badgered and disbelieved, no one likes a person who systematically favors one nation to all others.

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The F-14 cobra is a real thing, per my report that got it buffed recently.

@Aurelian_ROW I haven’t consistently favored any nation. US has enough bug reporters, so do other countries. My primary focus has been assisting the French community with their reporting and then doing some Russian stuff myself. The fact of the matter is, I have 11 years and 15,000 hours in the game and I’ve played all nations. The only one I am biased against is Britain, cuz I’m American. Just how it is.

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I am aware of your report but ingame it seems to be capable of maintaining such AoA much longer than described in the the documents provided in your report said

but thats off topic anyways

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If you wanna do some testing and share it with me in DM’s we can compare and maybe make a report.

Back on topic now.