War Thunder

Datamine for AIM-9B, 9E and 9L [1.85.0.70]

Quick Foreword

I'm not completely confident that I know what each value means in these game files. Some of my conclusions are based on inference. Also, the AIM-9E (a later version of the Sidewinder used by USAF) is currently not used, and thus the current data for that missile might be different from when it inevitably gets added.

Breakdown of Key Missile Characteristics

At first glance, Gaijin seems to have done some impressive work.

  • Every missile has a "mass" and "massEnd" value; for the 9B, the "mass" is 70 and "massEnd" is 50.3. This is more than likely the value for a missile's mass before and after it has used its rocket fuel. In effect, missiles should become more maneuverable towards the end of their burn, where their maximum speed and minimum weight is achieved. Overall, this isn't a particularly important detail, but it shows they didn't cut any more corners than necessary (e.g. random tracking failure doesn't appear to be a thing).

  • "timeFire" seems to represent how long the rocket motor lasts.

  • "force" might be the amount of thrust produced, but I'm not sure what units the values are in. For the 9B, the "force" value is 17,619. However, this can't be in either lbf or N, as this would be waaaaaay off from the IRL stated thrust of 3,860lbf (see references).

  • "warmUpTime" and "workTime" — these are pretty self-explanatory. "warmUpTime" defines how long it takes for the missile to warm up, "workTime" defines how long the missile remains active before falling back into an inactive state.

Now for some more interesting stuff…

  • "uncageBeforeLaunch", which can be true or false. Essentially, every AAM has a seeker head that moves around inside the missile to keep track of its target. Prior to launch, however, the seeker head is kept in a 'caged' state, wherein the seeker cannot move and will only face directly forward. "uncageBeforeLaunch", then, defines whether or not the seeker head can be 'uncaged' before being launched. This is extremely important when trying to take down maneuvering or tight-turning targets, as an uncaged seeker allows you to 'lead' the target prior to launch. Leading a target with a missile might sound silly, but it really isn't; drag, turning limits and G overload are all modelled, so helping the missile get to as close a straight trajectory as possible is necessary to achieve a hit. This should be obvious to those who have already used either the AIM-9B or R-3S, where even a low angle between you and your target's trajectory will result in a miss, with the missile not being able to turn hard enough.

  • Next is "endSpeed" and "machMax". "endSpeed" is an odd value, since it's literally the same for every missile: 800. On the in-game stat card, this would be displayed as "Maximum speed on the trajectory: 800m/s". However, the missiles clearly do not, if ever, reach 800m/s, and I think this is due to the simulation of drag and/or the missile's maximum allowable mach (the AIM-9B has a "machMax" of 1.7, even though 800m/s is about mach 2.3 at sea level).

  • The values "maxDistance" and "rangeMax", despite sounding very similar, apparently contradict each other. On the AIM-9B, for example, the "maxDistance" is 12,000, and I assume this is in metres. Its "rangeMax", however, is 10, and this might be in kilometres. How the two differ, though, is unknown to me. I should also note that there is a "minDistance" value, usually set to about 30m for all missiles.

  • Another value somewhat related to those two is "timeToLive", which is likely in seconds. "timeToLive" likely defines how long a missile can 'live' for before turning off. If anything, this probably simulates the battery life of a missile's guidance system.

  • "loadFactorMax" — quite simply, this how many Gs the missile can pull and is a good indicator of how effective a missile will be at countering evasive maneuvers.

  • From the "proximityFuse" section: "timeOut" and "radius". "radius" is just the radius of the proximity fuse, while "timeOut" might be the delay before the warhead actually explodes (for every missile the "timeOut" value is 0.5).

Here are a bunch of values specific to the "irSeeker" section of the missile data:

  • "rangeBand0", "rangeBand1" and "rangeBand2". These are most likely the maximum lock distances (in metres) from the rear, front, and side aspect of an aircraft. The earlier rear-aspect missiles only have a "rangeBand0" and "rangeBand2", meaning that "rangeBand1" is likely from the head-on aspect. Take these with a grain of salt, however, as aircraft engine heat does interact with lock range (if you try to lock someone while they're landing, you'll generally have to close to within 1km due to the enemy being on idle throttle, and thus having a lower engine temperature).

  • "fov" defines the field-of-view of the missile seeker head.

  • "lockAngleMax" defines the maximum angle at which the seeker will achieve a lock.

  • "angleMax" defines how far the seeker head itself can traverse. I.e. an "angleMax" of 25 means the seeker head can traverse 25 degrees off-centre. A larger value means the missile can effectively pull a bigger lead on the target (in the case of the AIM-9L, the value is 40, meaning it can just about track a target moving perpendicular to it).

  • "rateMax" is likely the maximum traverse rate of the seeker head. As we'll see below, most seeker heads have fields-of-view between 2 and 5 degrees, meaning that the seeker head itself will constantly need to move around in order to keep track of its target. Low traverse rates can potentially be abused by making a sudden high-G manuever just before a missile reaches you; the seeker head will not be able to keep up and the missile will fly straight past.

  • Lastly, "minAngleToSun" denotes the angle at which the seeker will lock onto the sun's heat signature instead of an enemy aircraft. Curiously, the Firestreak has a value of 0, meaning you need to have the seeker head pointing directly at the sun for it to be spoofed.

Unfortunately, I couldn't identify a value that defined the maximum allowable G-overload for launch. Currently, the AIM-9B can't be launched above ~4G.

Data for AIM-9B, 9E and 9L

I've made a Drive spreadsheet for the listed missiles and will continue to update it in the future. Don't expect immediate and/or regular updates, though; I don't get payed for this.

Some notable points include the AIM-9E's 10G overload and the missile being uncaged pre-launch, which will make the AIM-9 usable against low-speed manuevering targets. We likely won't see the 9E until the F-4 Phantom is in the game, though, at which point AIM-7 Sparrows will also be available.

As for historical accuracy, the AIM-9B and 9L's rocket motors should last for 2.2s and 5.23s respectively, whereas in-game they last for 2.1s and 2.3s (9B motor should put out 3860lbf, 9L should put out 2660lbf). Range is awkward to assess, as it depends on many other factors external to the missile, such as relative speed between launch and target aircraft, absolute speed of the launcher and target, and altitude. The AIM-9B's SMC sheet states a range of "approximately 6000 feet (1828m) at sea level and 35,000 feet (10,668m) at a 50,000 foot (15km) altitude". From in-game testing, the 9B seems to have a range of about 2.5km at sea level if both aircraft stay at about mach 0.9, so it might actually be overperforming.

References for missile data

AIM-9B SMC

AIM-9L SMC

Original post


© Post "Datamine for AIM-9B, 9E and 9L [1.85.0.70]" for game War Thunder.


Top-10 Best Video Games of 2018 So Far

2018 has been a stellar year for video game fans, and there's still more to come. The list for the Best Games of So Far!

Top-10 Most Anticipated Video Games of 2019

With 2018 bringing such incredible titles to gaming, it's no wonder everyone's already looking forward to 2019's offerings. All the best new games slated for a 2019 release, fans all over the world want to dive into these anticipated games!

You Might Also Like

Leave a Reply

Your email address will not be published. Required fields are marked *