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Air-to-Air Missile Discussion


Shein

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I feel as though this thread needs to be split into three very different topics.

 

1. Kinematics which imo is the most important as it's one of the easiest things to fix and EVERYTHING else stems off of getting it right.

 

2. Navigation and to some extent maybe counter measure susceptibility. Much much harder to do anything with as that's all game code stuff due to being in the backend you don't really have much to say beyond "It'd sure be nice if my missile doesn't pull 30g as soon as it comes off the rail for no reason"

 

3. AI. Well... Don't have much else to say on that really.

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I agree with your reasoning, but as far as the 1st point is concerned, what exactly do you believe is broken with regards to the kinematics of the specific missiles. (Or are all of them broken?) Im not at liberty to pore over the graphs you have extrapolated ATM so if you could simply state where you believe the physics fall short? In layman's terms if at all possible :)

 

Through some pretty extensive testing on my end, I've found that the physics engine in the game is pretty reliable and behaves more or less as it should for a simplified real life simulation. So if we start on that assumption we have two things to tackle.

 

1. Thrust. Pretty much all the thrust data on all the missiles is known. We know how much fuel is in every missile, what fuel is in every missile, and thus what the Isp is (a yard stick I know) to generate a thrust profile. This is more than accurate enough for a video game.

 

2. Drag Coefficient. Since the game engine models atmosphere pretty well, all we need is an accurate Cd curve at sea level and the game engine will do the rest, and this is what I've found.

 

There are some flaws in the game engine's generation of Cd however. For instance a modifier needs to be added for when the engine is on. This is because it reduces drag by disrupting the vortex that forms as the shockwave travels over the body. In a nutshell, motor on = less drag.

 

Once these kinks have been worked out you're then able to, through mostly trial and error, build a Cd curve that forces the missile to behave to how we know they should at Sea Level from real world and CFD analysis.

 

This is what I did in the AIM-9L Variant curve back on page 3 of this thread. The only thing is lacks is the motor on/off which would more or less correct the slight discrepancy it has compare to the actual flyout performance charts.

 

We do this for every missile that players use and you've resolve the kinematic performance.

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Is the caff rejection, going to be updated, all SARHs are showing amazingly bad performance once chaff is introduced, ARHs dont fair much better either.

 

Then I will say you the R-27ER have not the inertial/Radio corrected guidance implemented in game (why?). In the last Phase of the trayectory is when the R-27 use the semi active head seeker, at this Moment the aircraft launcher is in a distance that the chaff have poor effect.

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Because it isn't implemented for anything in the game.

 

Then I will say you the R-27ER have not the inertial/Radio corrected guidance implemented in game (why?).

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I don't know, but I will bring it up. I know that the devs believe that from straight behind, the chaff should be completely screening the plane. I don't think that's true, but it's a deep argument and not necessarily easy to make or even simulate without doing a lot of extra work.

 

Is the caff rejection, going to be updated, all SARHs are showing amazingly bad performance once chaff is introduced, ARHs dont fair much better either.

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I used to play flight sims like you, but then I took a slammer to the knee - Yoda

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The 120 has a better BC even if they have the same Cd. The 120 has a lower Cd than than ER. The ER will slow down faster.

 

Still missing my point,

Lower Cd doesn't guarantee slower deceleration... If missile mass is higher the inertia wants it's to keep going... And if there is more mass and inertia to overcome more drag then heavier missile even with higher drag will decelerate slower.

 

And there is also to consider that R-27er is faster missile, higher top speed, so as it starts decelerating even if it decelerates faster, it's already further out then 120.

 

I don't know what drag coefficients for both missiles are though... I doubt the 120 has 1/2 the drag coeff of ER... But I could be wrong as I don't know this

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I don't know, but I will bring it up. I know that the devs believe that from straight behind, the chaff should be completely screening the plane. I don't think that's true, but it's a deep argument and not necessarily easy to make or even simulate without doing a lot of extra work.

 

It seems a bit much that it would miss a plane that's flying straight and just popping a bit of chaff, thats for SARHs.

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Still missing my point,

Lower Cd doesn't guarantee slower deceleration... If missile mass is higher the inertia wants it's to keep going... And if there is more mass and inertia to overcome more drag then heavier missile even with higher drag will decelerate slower.

 

And there is also to consider that R-27er is faster missile, higher top speed, so as it starts decelerating even if it decelerates faster, it's already further out then 120.

 

I don't know what drag coefficients for both missiles are though... I doubt the 120 has 1/2 the drag coeff of ER... But I could be wrong as I don't know this

 

I agree, that a lower Cd on it's own doesn't mean much. However if all other variables are the same, it will have a lower drag force. But, the ER has a larger area and a larger Cd which means it'll have a larger drag force.

 

Not only does it have a larger Cd/Fd but it has a lower BC. This means that it will slow down at a faster rate.

 

If both missiles appear in space at Mach 4, the ER will slow down at a faster rate than the 120. I don't know the Cd of the ER either, so I don't know how much larger it's going to be than the Charlie. At some point I'll get it CFD'd.

 

Edit: Formating, grammar.


Edited by IASGATG
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A lower Cd doesn't necessarily mean a slower deceleration, but it will mean less drag force. If the 120 has a lower Cd and a higher BC it will slow down slower. If both missiles appear in space at Mach 4, the ER will slow down at a faster rate than the 120. I don't know the Cd of the ER either, so I don't know how much larger it's going to be than the Charlie. At some point I'll get it CFD'd.

 

It depends on ratio of differences in those mass and drag coeff. If they are both equal... they will decelerate the same, but if one is higher than the other then they won't.

 

And in space drag is 0 zero, so regardless of mass or shape they will not decelerate at all... Inertia will not be lost and both missiles will just keep going (like space travel where engines are only used to change trajectory or velocity)

No longer active in DCS...

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Still missing my point,

Lower Cd doesn't guarantee slower deceleration...

 

In this case it does. I even did the actual math for you, computing the drag forces acting on each missile.

 

And there is also to consider that R-27er is faster missile, higher top speed, so as it starts decelerating even if it decelerates faster, it's already further out then 120.

 

At very high altitudes where the drag forces are quite low it may/probably will make a difference, because you're not working so hard to reach a peak speed.

 

I don't know what drag coefficients for both missiles are though... I doubt the 120 has 1/2 the drag coeff of ER... But I could be wrong as I don't know this

 

It doesn't need to have 1/2 the Cd of the ER.

 

Even if we consider the same Cd:

 

- Empty AMRAAM weighs in at over 50% of empty R-27ER

- Drag force on AMRAAM is less than 50% of R-27ER

 

If you accept that the Cd of AIM-120 is lower than that of R-27ER, and it really should be, then the 120 starts edging out the ER even harder in the ability to just fly on.

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Reminder: SAM = Speed Bump :D

I used to play flight sims like you, but then I took a slammer to the knee - Yoda

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It depends on ratio of differences in those mass and drag coeff. If they are both equal... they will decelerate the same, but if one is higher than the other then they won't.

 

And in space drag is 0 zero, so regardless of mass or shape they will not decelerate at all... Inertia will not be lost and both missiles will just keep going (like space travel where engines are only used to change trajectory or velocity)

 

With the numbers you've provided which for the napkin maths we're doing is fine, the 120 has more BC which means it slows down at a lower rate.

 

In a Drag Force equation, the 120 has less force being applied to it.

 

I don't understand where you're getting lost.

 

In the two main models that are used to govern how fast an object slows down in air, both say the 120 slows down at a lesser rate than the ER, despite the ER having more momentum behind it.

 

To be honest, I shouldn't really bring up Fd since the main comparitor here is BC which has the 120 in the lead..


Edited by IASGATG
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Because it isn't implemented for anything in the game.

 

Thats correct... But we are Pilot and not Buks and Hawk Operators. We could understand that this guidance could be implement later for Air-defences...

 

So the answer: inertial/Radio corrected is not implemented for anything in the game. It is quite unfair when the main weapon of the Su-27 are these missiles

 

The F-15 can kill until 3 Targets at the same time, TWS with ECM countermeasure, AIM-120 with Home of Jame mode... Count down for Active head seeker activation and you say us this answer.

 

 

My god...!


Edited by pepin1234

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I think you will be surprised to find that when you get into an F15 cockpit, that the thing is not an insta kill swtich.

 

One other thing to consider, if ED released a patch tomorrow that turned FC3 planes into fully developed DCS products (i.e. A10C) these planes would be MUCH MUCH LESS evenly matched than they are now.

 

You have to consider that this is not a competitive game (even though its being played as one by a lot of the multiplayer community), its a simulation.

 

I beg to differ with your assessment. A simulation represents its entities characteristics as closely as is possible without consideration of adjacent entities capabilities. In essence, no consideration should be given to how evenly matched one entity is to another.

 

If any element of the SU-27's characteristics and or its weaponry were deliberately diminished to make it equal with a lesser aircraft, then it wouldn't even be a reasonable representation of the SU-27, would it?

 

Same can be said for any aircraft in the simulation.

 

How can it be stated for example, that the Aim-120 is modeled as closely as humanly possible to the real thing, but since it outperforms an opposing sides similarly purposed missile, that its performance should be suppressed. That in and of itself along with a continued developmental approach in this manner would totally undermine what is being termed, a simulation.

 

This is a game developers goal and objective -- To equal out the playing field. It should never be (IMHO) the goal of simulation developers.

 

And in all honesty, I do not believe that is what ED is doing with their simulations.

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I beg to differ with your assessment. A simulation represents its entities characteristics as closely as is possible without consideration of adjacent entities capabilities. In essence, no consideration should be given to how evenly matched one entity is to another.

 

If any element of the SU-27's characteristics and or its weaponry were deliberately diminished to make it equal with a lesser aircraft, then it wouldn't even be a reasonable representation of the SU-27, would it?

 

Same can be said for any aircraft in the simulation.

 

How can it be stated for example, that the Aim-120 is modeled as closely as humanly possible to the real thing, but since it outperforms an opposing sides similarly purposed missile, that its performance should be suppressed. That in and of itself along with a continued developmental approach in this manner would totally undermine what is being termed, a simulation.

 

This is a game developers goal and objective -- To equal out the playing field. It should never be (IMHO) the goal of simulation developers.

 

And in all honesty, I do not believe that is what ED is doing with their simulations.

 

 

Haven't you both said the same? *_*

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You have to consider that this is not a competitive game (even though its being played as one by a lot of the multiplayer community), its a simulation.

 

I disagree here. Flying The F-15C/SU-27/Mig-29 competitive is the main part of the simmulation of those air planes. To deploy tactics better, react faster and deploy your weapons better than the other. Even in single player. When you playing this game you want to be better than the AI and other players right? Otherwise it would be a crash and burn simmulator. Or a "Fly patterns around the terrain and aim your advanced weapons at the ground simmulator". Sorry if you are not competitive in a Digital Combat Simmulator you will get splashed by every AI or player.

 

While we also fly like you do we also want to kill our opponent in the most efficient way before he can kill you. If you take out the competitive part you won't even have a Digital Combat Simmulator anymore. You will be gazing and turning at beatifull created switches and look around the cockpit.


Edited by winchesterdelta1

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I think you will be surprised to find that when you get into an F15 cockpit, that the thing is not an insta kill swtich.

 

One other thing to consider, if ED released a patch tomorrow that turned FC3 planes into fully developed DCS products (i.e. A10C) these planes would be MUCH MUCH LESS evenly matched than they are now.

 

You have to consider that this is not a competitive game (even though its being played as one by a lot of the multiplayer community), its a simulation.

 

I understand what you said, but honestly I dont find any relation with a full DCS Level for DCS Gamers and a guidance mode that can be added with a couple of entry keys.

 

I believe ED should remain modules with FC3 Level, lot of Gamers want something like that too and this is Money of course, but this is not the Point here.

 

YES maybe is hard for Players fight against a comprehensive (Close to reality) R-27ER/R-77 Missiles.

 

We (the Sukhoi and Mig pilots) have bought this game to make happy and proud the F-15 pilots? while we must accept our Missiles are a fail at 10/15/20km (the R-77) and the R-27 is really broken.

 

When an Aim-120 miss, it is because the Su/Mig have evade with lot of maneuver or the new guys Launch at 50/40 km. This is not a Problem of the Aim-120 in game. This is a Problem that they dont know do a good fight and Need practice.

 

When you see Su/mig pilots saying constantly the R-27/R-77 are broken and in the other side you see the F-15 pilots saying NO, all the Missiles are broken. What is the interrogant?


Edited by pepin1234

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I disagree here. Flying The F-15C/SU-27/Mig-29 competitive is the main part of the simmulation of those air planes. To deploy tactics better, react faster and deploy your weapons better than the other.

 

That is the point you're not grasping; tactics are AIRFRAME SPECIFIC, based on their relative strengths. Comparing raw competition absent of that context is a worthless exercise when discussing how a simulation functions.

 

This is not a balanced tilt with two competitors on horseback in the lane, with lances of the same length, shields the same size, armor of the same fashion, and horses of the same stud. This is dissimilar air combat. You will *not* find 1:1 balance within that context.

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I disagree here. Flying The F-15C/SU-27/Mig-29 competitive is the main part of the simmulation of those air planes. To deploy tactics better, react faster and deploy your weapons better than the other. Even in single player. When you playing this game you want to be better than the AI and other players right? Otherwise it would be a crash and burn simmulator. Or a "Fly patterns around the terrain and aim your advanced weapons at the ground simmulator". Sorry if you are not competitive in a Digital Combat Simmulator you will get splashed by every AI or player.

 

While we also fly like you do we also want to kill our opponent in the most efficient way before he can kill you. If you take out the competitive part you won't even have a Digital Combat Simmulator anymore. You will be gazing and turning at beatifull created switches and look around the cockpit.

 

There is a disagreement in definition here. For some people a competitive game is one where balance is one of the primary goals. This is fine for non simulators, but obviously it can be an issue with simulators.

 

I think what GoodDriver is saying is that this isn't a game where things are going to be balanced between all sides innately.

 

However, as winchester said, you can still be competitive in DCS even if it is a sim and not perfectly balanced.

 

When an Aim-120 miss, it is because the Su/Mig have evade with lot of maneuver or the new guys Launch at 50/40 km.

 

All the missiles seem to be about the same to me. The 120 does plenty of non sense. I have had it miss a non maneuvering look up target that was well within range. The 120 just suddenly died or went stupid.

 

There was also this that I got on tape:

 

 

 

Granted it is very close to Rmin, but not quite past that limit. I also made sure that the missile was pointing right on the dot when I fired, yet it decided to wander off into space.

Awaiting: DCS F-15C

Win 10 i5-9600KF 4.6 GHz 64 GB RAM RTX2080Ti 11GB -- Win 7 64 i5-6600K 3.6 GHz 32 GB RAM GTX970 4GB -- A-10C, F-5E, Su-27, F-15C, F-14B, F-16C missions in User Files

 

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Because it isn't implemented for anything in the game.

 

Well, when it is, it will make thing interesting. I have a question for you though: Is R-27ER seeker active right after launch or only in terminal phase? If the latter is the case, implementing this into DCS would definitely increase the Pk.

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