How does the SD-10 missile compare to the AIM-120C?

We've spent countless hours inspecting and comparing curves to our RL data and CFD curves, the most prominent ones being Cx0 and time-to-range. It's a step backwards to suggest that we should use in-game data as reference and overthrow all the previous works.

IMHO you need to re-visit that CFD because something isn't being interpreted correctly here. The missile nose cone, the relative poor boat-tail and mass of fins aren't likely to allow you that sort of coefficient graph shape.

 

 

Edit: I take my tweet back (LOL). This can certainly be possible, I just found the AIM-9 radar guided variant does it. However, it also has a much, much higher drag coefficient overall so my suggestion below stands:

 

 

 

 

Also, correct me if I'm wrong here, because I've done a lot of digging but I could easily get some things wrong:

 

 

The SD-10/PL-12 are not the same missile, but, at the same time they are both derivatives of the AIM-7E. As in, AIM-7E -> Aspide -> PL-12.

 

 

So my immediate instinct to get the missiles 'back to reality' is to put that AMRAAM drag curve on there and put the AIM-7F rocket motor into it.

 

 

I'm not claiming either is completely correct, the rocket configuration may have changed, and the missile itself is probably a little draggier than the 120 for bunch of reasons.

 

 

However, your drag is definitely too low (easily proven from test shots taken in-game compared with IRL data points provided, AFAIK, by you), and the rocket motor as you've defined doesn't seem quite right, namely:

 

 

You've got 70kg of fuel (sparrow has less, and it's a heavier missile) with a 6sec boost and 4 sec sustain stage. I would go with 4 sec boost and 10 sec sustain - lower the sustain power a bit, that's if you don't simply use the AIM-7F/M rocket motor definition.

 

 

Yes, the missile will be slower and will slow down faster ... and it will be more correct. Tune from there to hit your RL data-points. Best data-points involve time-to-distance, directly or indirectly computed.

Thanks for the suggestion. We cross-checked with other official sources that the CFD curve is not wrong. But the current missile model DCS has cannot hit all our data-points at all altitudes.

IRL the second-stage boost will not happen immediately after the first-stage. It acts as terminal activate phase boost. Maybe we'll see improvement on the missile API that enables simulation of such aspect.

It is the missile team's decision so I can just talk about it.

We've spent countless hours inspecting and comparing curves to our RL data and CFD curves, the most prominent ones being Cx0 and time-to-range. It's a step backwards to suggest that we should use in-game data as reference and overthrow all the previous works.

I can't disagree with you. I absolutely understand your point. It just that right now it doesn't fit in the same environment as the rest of the modules. Whether ED will update it's missile to fit yours and when is still unknown. Hopefully this will happen and everyone will be happy :)

I can't disagree with you. I absolutely understand your point. It just that right now it doesn't fit in the same environment as the rest of the modules. Whether ED will update it's missile to fit yours and when is still unknown. Hopefully this will happen and everyone will be happy :)

In my opinion, its not about fitting in. One methodology or the other is closer to reality than the other. Which one it is? We could argue all day about. I would rather aircraft weapons be modeled to the methodology that gets the closest results to their data.

Now obviously, there will be limitations and degrees of inaccuracy, but hopefully that is minimized to the extents possible currently within DCS.

Which ever methodology is more accurate should be followed, and with time, the other aircraft/weapons, if provided the same methodology creates a more accurate simulation for them should be transferred over.

That is my opinion at least, as mission devs/server hosts can balance things accordingly if they so wish. But the developers should never sacrifice constructing something as accurately as they can just because other items are not to the same standard.

We hope that the standard/methodology Deka Ironworks is following is correct and that the missile performs as closely to their references as can be done with the sim currently, as with any simulation there will be deviation due to various reasons.

I can't disagree with you. I absolutely understand your point. It just that right now it doesn't fit in the same environment as the rest of the modules. Whether ED will update it's missile to fit yours and when is still unknown. Hopefully this will happen and everyone will be happy :)

Maybe we should start a new thread in the DCS World Forum to ask ED to revisit the aim120 ASAP, cause obviuosly this is a case of aim120 not performing rather SD10 doing something wrong.

So you guys are going to keep on complaining until the developers give up their research and go by your opinions? I doubt the developers will make their data available to public and ED themselves said that they require proof before even allowing the weapons to be implemented so I doubt anything will change at this point.

 

 

The people argueing in the forum are ones with tens of thousands of post count so they have nothing better to do than just argue for days. Stop getting so upset that someone told you no and go fly whatever else module you enjoy.

Same could be said about you. All you do here is spamming this thread with posts to tell people to shut their mouth, when they provide interesting data, which you do not...

So please, unless you have any data to back up your claims, I would ask you to stop spamming here.

Same could be said about you. All you do here is spamming this thread with posts to tell people to shut their mouth, when they provide interesting data, which you do not...

So please, unless you have any data to back up your claims, I would ask you to stop spamming here.

I never claimed anything which would need backing up. Furthermore the data which most people have provided are comparison with AIM-120C and mentions of some official document claiming that the missile performance is between AIM-120B and AIM-120C without providing the source or legitimacy of that claim.

I never claimed anything which would need backing up.

That's exactly my point: You're not contributing to this thread in any meaningful way. If you don't like this thread then don't read it and do something else, but I find this discussion and the information provided by it quite interesting, so I would ask you to stop telling people, who do provide information, to shut up.

I would ask you to stop telling people, who do provide information, to shut up.

I never told anyone to "shut up". Especially not the ones providing any relevant data. That is like me saying that you are telling me to shut up or go away.

So far the information being shared here is just the repeated statements. Lower drag of missile because they do not match with AIM-120C. Then the developers state that they have modelled SD-10 the best they could but the limiting factor is ED missile API. Then some more numbers are provided and they ask to lower the missile drag followed by developers response that their data is accurate to the abilities of this game engine. Then more talk about missile drag anyway and it goes on for days.

In the mean time, the people who are reading this thread think that this missile is overpowered, some even now claiming that they have done so to boost up sales. Nothing good is coming from this thread in the end.

I'm sure despite what I have said so far, this will keep going on loop unless even ED jumps in at this point.

I never told anyone to "shut up". Especially not the ones providing any relevant data. That is like me saying that you are telling me to shut up or go away.

 

 

 

So far the information being shared here is just the repeated statements. Lower drag of missile because they do not match with AIM-120C. Then the developers state that they have modeleed the best they could but the limiting factor is ED missile API. Then some more numbers are provided and they ask to lower the drag followed by developers response that their data is accurate to the abilities of this game engine. Then more talk about missile drag anyway and it goes on for days.

 

 

In the mean time, the people who are reading this thread think that this missile is overpowered, some even now claiming that they have done so to boost up sales. Nothing good is coming from this thread in the end.

 

 

I'm sure despite what I have said so far, this will keep going on loop unless even ED jumps in at this point.

I doubt ED will jump unless forum rules are abused.

I see no problem if some people do not agree with deka statements, especially people who knows what they are talking and bring numbers behind their claims. It's a discussion between both sides, and as deka devs are also replying just shows they are also interested in the discussion.

The only one who keeps repeating "close the thread" is you, while no one forces you to follow it. When the thread gets exhausted or some end agreement is reached it will die by itself.

Thanks for the suggestion. We cross-checked with other official sources that the CFD curve is not wrong. But the current missile model DCS has cannot hit all our data-points at all altitudes.

 

IRL the second-stage boost will not happen immediately after the first-stage. It acts as terminal activate phase boost. Maybe we'll see improvement on the missile API that enables simulation of such aspect.

 

It is the missile team's decision so I can just talk about it.

You are describing what we call a 'dual pulse rocket', which is interesting - while not a new idea, it would be the first AAM we know of that actually implements it.

I believe the new missile FM supports it (you are using the 'previous generation'), I will check.

Do you have any data about SD-10 than you can actually share?

Ie. time-distance, propellant weight and grain set up etc?

Yes, I requested the thread to be locked twice and stated my reason behind it as well. Yet here we are, argueing. Most you guys are doing the same as me, just agreeing or disagreeing rather than providing much relevant information.

Please stick to the topic of the post instead of argueing about pointless things. I am also following this thread out of interest and will respond when I feel like something does not seem right with the information provided.

I can make dinner twice this week with the amount of salt in this thread.

Don't wash the plates off without special treatment.

It would eventually melt the icecaps both north and south.

You are describing what we call a 'dual pulse rocket', which is interesting - while not a new idea, it would be the first AAM we know of that actually implements it.

I believe the new missile FM supports it (you are using the 'previous generation'), I will check.

 

 

 

Do you have any data about SD-10 than you can actually share?

Ie. time-distance, propellant weight and grain set up etc?

jane's did conduct an interview with the manufacturer - it was confirmed to be dual grain minimum as the manufacturer wanted various characteristics to be implemented (the missile to be able to distance itself fast from the airplane carrying it, being able to be used in visual range engagements/dogfights, have a long sustain stage for maximum range engagements - i.e. don't spend energy fighting wind resistance, depending on target height etc).

afaik 3 grains (including booster/main motor) are not uncommon in the industry

Nozzles are always classified, this was suspected to have variable geometry and probably thrust vectoring (given the number of G's it can pull) etc

multi grain boosters/main motors are common in the industry, many missiles tend to use them, along with various other implementations for throttling propulsion / fuel consumption (e.g. by changing the shape and/or diameter of the nozzle). The nozzle also has to have different characteristics depending on the operating altitude as the aerostatic pressure changes - generally i would assume that missiles able to work at 80/90k ft and at 1k ft will have something more advanced than a welded conical piece of tin at the end :P

ultimately this is all garbage and ramjet is the future anyway, so let's hope for the meteor to become available sometime soon :P

i'm just a fanboi not a missile engineer but since you're asking for more resources hopefully these will pique your interest

variable shape nozzles (mostly talking about aerospike but explains why you need to have variable shapes):

https://en.wikipedia.org/wiki/Rocket_engine_nozzle

this is a good overview from some uni student re. throttling solid fuel engines (not so much of a problem for space travel as the conditions are not so much of an unknown compared to a/a missiles): https://www.quora.com/How-can-a-solid-fuel-rocket-be-throttled - lots of other good answers there etc

I'm sure if we get on the dev's good books they might be more inclined to share tidbits with hobbyists like us :)

throwing stones on the other hand and not giving someone the opportunity to engage in a meaningful dialogue (as when we start a conversation with absolutes and how wrong other person is) is likely to end up the same way as this thread has so far :)

Hi all,

 

The ED team will be reviewing A2A missiles, I can not give you a time frame currently but when we do we will be sharing more information with you all via the newsletter.

 

This is a hot topic and people are passionate, so please be nice to each other during the discussions.

 

thank you

Thanks, that's great to hear! :thumbup:

We've spent countless hours inspecting and comparing curves to our RL data and CFD curves, the most prominent ones being Cx0 and time-to-range. It's a step backwards to suggest that we should use in-game data as reference and overthrow all the previous works.

2 questions:

Should the SD-10 have equal speed, but be less draggy than this AIM-120C-D shot in this F-35 demonstrator sim?

It is identical to the same shot tested in DCS, you can easily replicate it:

https://media.giphy.com/media/Su1B6wyiTCKkPAiMMO/giphy.gif

Second question, during testing the SD-10 within <1km has shown to have off bore sight capabilities comparable to AIM-9X, making it a significantly better missile for dogfights than PL-5E II or R-73. Is this supposed to be this way?

haha that's pretty creative i have to admit :) also, nice vid, the f35 is truly amazing compared to our rust buckets

how can you tell what's the drag coefficient though lol, at best you can maybe compare flight times (not even that really the camera pans out from the flir view so you can't see exactly when the missile impacted?)

haha that's pretty creative i have to admit :) also, nice vid, the f35 is truly amazing compared to our rust buckets

 

 

 

how can you tell what's the drag coefficient though lol, at best you can maybe compare flight times (not even that really the camera pans out from the flir view so you can't see exactly when the missile impacted?)

You have visible time to impact on the hud which counts down and when it reaches zero they show the impact. Actually it seems like the dcs missile hits slightly earlier :)

+ 1 for the second question, it seems like we have a super weapon :)

Second question, during testing the SD-10 within <1km has shown to have off bore sight capabilities comparable to AIM-9X, making it a significantly better missile for dogfights than PL-5E II or R-73. Is this supposed to be this way?

So you claim that the SD-10 can currently hit a target 90° off-boresight in less than 1km range? Oh I need to see this one myself. This can't be right.

You have visible time to impact on the hud which counts down and when it reaches zero they show the impact. Actually it seems like the dcs missile hits slightly earlier :)

 

+ 1 for the second question, it seems like we have a super weapon :)

hey this is internet engineering truly at it's finest. Hardcore science like this deffo proves things and i now consider the matter closed

like..

how the two missiles impacted within like 0.5secs of each other. These lock-head guys are maybe a bit better at making assumptions about how stuff they actually build work. My keen eyes can detect a minimal 4% error margin compared to ED and deka.. I guess now I know where to spend my money on steam. Also their early access seems so much better than the stuff deka served us.. They're on steam right?

making any sort of assumptions about the level things are simulated in each sim, access to unclassified data etc is pointless, ED has to get their act straight and the sd10 is starwars tier fantasy. There's no chance in hell that one missile might be slightly faster but have a lower range compared to the other, bugs or anything else that doesn't imply the sd 10 is wildly inaccurate

After all this though, i'm still left with a question - where in the display of the better sim can we see the actual drag coefficient?

2 questions:

 

Should the SD-10 have equal speed, but be less draggy than this AIM-120C-D shot in this F-35 demonstrator sim?

 

 

It is identical to the same shot tested in DCS, you can easily replicate it:

 

https://media.giphy.com/media/Su1B6wyiTCKkPAiMMO/giphy.gif

 

 

Second question, during testing the SD-10 within <1km has shown to have off bore sight capabilities comparable to AIM-9X, making it a significantly better missile for dogfights than PL-5E II or R-73. Is this supposed to be this way?

Ill take you up on your question, the first part can't really be used as its yet another simulator and not hard data. The same could be said about a certain F-16 sim.... you just should not use comparisons to other simulators because you don't know the degree of accuracy they follow. Maybe they are accurate? Maybe they aren't. You just don't know without data to verify. Atmosphere and guidance immediately come to mind as some reasons a SIM can be off even with a correct missile model. And that being a technology demonstrator, you have no clue if they even wanted to model it correctly. So once again, that is why any reference to hard data is preferred. And even then, hard data can be debated for numerous reasons, but in general its a much better place to start.

Edit- Should not instead of cannot, because you shouldn't argue based on that data, but you can.

Second part, while its probably unlikely for it to actually be able to do that, I cannot confirm, but I've seen many missiles do similar to what you described in DCS. AFAIK the SD-10 uses the 120 seeker with counter measure reject changes due to DCS API limitations currently. Someone can correct me on that if I am wrong.

Additionally, I have seen R-73s, Aim-54s and etc fly loops around planes, and all active radar guided missiles can still guide/make corrections after radar contact is lost even before they are active. I have seen 54s fly past an aircraft and make a complete 180, so its not out of the question that the SD-10 might show similar behavior. So while performance of the SD-10 in other aspects can directly be attributed to the SD-10, I think this aspect isn't a result of Deka's modeling but more limitations of DCS currently as similar has been shown in other aircraft.

I think what you saw, probably stems from the fact that the missile knows where the aircraft is at all times even if the aircraft radar doesnt have a lock. So normally, the aircraft would pass outside of seeker limits and the missile would "lose lock" but it does not currently as the missile still knows where the aircraft is and will try to reconnect if it has the energy necessary to do so. That applies for Aim-120, R77, 54 AFAIK.

I think someone actually referenced the same earlier in a linked post to Chizh. Something along the lines of "active radar missiles making guidance corrections even when radar is off before the missiles' seeker is active".

We cannot make any guesses based on the F35 simulator shown of YT. If I were the MoD of a country, and I was publicly showing a simulator of my top fighter, I would probably reduce by a significant margin the features/range of the weapon shown there, cause any resemblance to real characteristics could be used by potential enemies and are downright top secret material.

So it is a good showcase of overall features, easy interface and lethality but i don't think it can be use as a benchmark for weapon systems.

Interesting comment in FB page

Interesting comment in FB page

Directly contradicts what ED said earlier today on how the team will be reviewing A2A missiles in the coming months