[WAD] AIM-120C (and other AA missiles) Speed falloff

[AdmiralSteve]

I've noticed that the AIM-120C as well as other AA missiles have significant speed falloff well within their max range. This is a screen shot, .save file as well.

AIM-120 C Speed Falloff.png (1.63 MiB) Viewed 1317 times

AIM-120 C Speed Falloff (2).zip

(4.07 MiB) Downloaded 28 times

[Dimitris]

Hi,

Yes, this is by design. The nominal "maximum range" is not the burnout point, but rather the outer range at which the missile still has sufficient speed.

[mithrilsword]

Hi,

Yes, this is by design. The nominal "maximum range" is not the burnout point, but rather the outer range at which the missile still has sufficient speed.

Why PL-15, which supposed to have similar firing range, having much shorter powered range comparing to AIM-120D?

[Dimitris]

AIM-120D reportedly uses a dual-pulse rocket motor in order to maintain a high energy reserve at its maximum range. We have no information on the PL-15 using a similar (or other extended-range type) rocket motor type.

If you have reliable information that suggests it does, feel free to make a DB request: https://github.com/PygmalionOfCyprus/cmo-db-requests

[Nikel]

This is the source of the Wikipedia article on the PL-15 missile.

Wood, Peter; Yang, David; Cliff, Roger (November 2020). Air-to-Air Missiles: Capabilities And Development In China (PDF). Montgomery: China Aerospace Studies Institute

https://www.airuniversity.af.edu/Portal ... 0tqA%3d%3d


Also

https://www.globalsecurity.org/military ... /pl-15.htm

http://chinese-military-aviation.blogsp ... les-i.html

[Dimitris]

As I previously said:

If you have reliable information that suggests it does, feel free to make a DB request: https://github.com/PygmalionOfCyprus/cmo-db-requests

[mithrilsword]

As I previously said:

If you have reliable information that suggests it does, feel free to make a DB request: https://github.com/PygmalionOfCyprus/cmo-db-requests

Sadly with absence of such significant feature, most near-future scenario (which as we know, focused on Sino-US conflict) were barely playable and enjoyable as no-brainly easy with US side.

I understand what happens during the BETA, but right now will have to roll-back to previous version for playability (or redisign most of the previous scenarios and workshop scenarios).

[thewood1]

Just ran a bunch of tests. The PL-15 (non-export) has a max flight range of about 83nm. The AIM-120D has a max flight range of about 85nm. Just pointing out that there's only a couple nm difference.

Just checked and from the Chinese Air Power by Gordan. And thats the most recent I have seen any info published. The rest of the sources were from 2016 to 2018. Page 358 states that the PL-15 has a max flight range up to 200 km.

https://www.amazon.com/Chinese-Air-Powe ... C59&sr=8-1

Modern Chinese Warplanes: Chinese Naval Aviation - Combat Aircraft and Units also states that the PL-15 might have a range as high as 200km.

https://www.amazon.com/Modern-Chinese-W ... C61&sr=8-2

That 200km is 107nm. Thats not powered flight range, but actual flight range. Thats theoretical range at perfect launch parameters. I think in CMO I can push that over 100nm if I take the J-11 to max altitude and speed, I might be able to get to 100nm. CMO has max range at 94nm. So I guess you could make an argument that your favorite AAM is shortchanged a little, but not much.

[Dimitris]

As I previously said:

If you have reliable information that suggests it does, feel free to make a DB request: https://github.com/PygmalionOfCyprus/cmo-db-requests

Sadly with absence of such significant feature, most near-future scenario (which as we know, focused on Sino-US conflict) were barely playable and enjoyable as no-brainly easy with US side.

I understand what happens during the BETA, but right now will have to roll-back to previous version for playability (or redisign most of the previous scenarios and workshop scenarios).

1. Make a DB change request at the GitHub tracker. So far you have not.

2. So, your entire strategy for a theater-level conflict hinges on a specific tactical weapon having (or not) a specific technical feature?

[mithrilsword]

2. So, your entire strategy for a theater-level conflict hinges on a specific tactical weapon having (or not) a specific technical feature?

I'm afraid YES in some scenario(with hundreds of both missile fired), have to redesign and recalculate military assets input on par with the new AAW trade-off rate.

[thewood1]

If you are that dependent on a few miles of range on one missile, I think something's wrong somewhere. Which scenario is it? Maybe someone can help with it.

[thewood1]

https://www.youtube.com/watch?v=o89BWqy-83U

A good demo of the new powered missile flight dynamics. If you look at PGat's video list, there is also a short tutorial on intermittent emcom settings.

Again, I can't recommend highly enough PGat's videos. I've been playing CMO/CMNAO for nine years and still learn a lot from him.

[Gainful]

The speed falloff is absolutely ludicrous. The AIM-120C has a max range of 60 nm but it drops to less than 900 kts in less than 15 nm! Its insane! You'd have to fire it at Sidewinder ranges for it to be even remotely effective. Its completely sapped the fun out of the game.

[thewood1]

I would suggest putting a save up. I'm not seeing that. Have tried multiple engagement combinations. And keep in mind the "C" is much more limited than the "D". There's a reason for swapping out the motor in the "C" in the "D" upgrade.

Screenshot 2022-06-26 065409.jpg (108.16 KiB) Viewed 951 times

Still at 1900 knots at 30 nm.

[bsq]

Basically the missiles, once the motor has burnt out are subject to the drag. The higher the missile, the less the drag, the longer the time of flight. Max range is the point it can still do a multi g manouevre to try to defeat the target, but if the target is a fighter, it will likely be less of a manouevre than the fighter can pull.

You do know that these missiles use two speeds to give the overall closure speeds.

Head on shots use the closure rate of the target as well as the speed of the missile. If the speed post burn out isnt good enough for your tactic, then why does it follow that the missile is modelled incorrectly?
I would hazard its your tactic thats wrong as the missile is following basic aerodynamic laws.

Head on, launch at around 2/3rds max range to achieve intercept at a point that gives you a second chance at a shot... shoot-look-shoot.

Tail chases, then shoot closer so the missile has a chance at running down the target, as you are subtracting target speed from your missile speed.

[thewood1]

You can have all of the detailed background you want to provide, but unless he provides less hyperbole and more detail, its a guess at what the poster is seeing.

[BDukes]

WRAs do need to be adjusted for many existing scenarios. That's fine, definitely a price of progress worth paying (IMHO ) however good dude thing to do would be to add that in the release notes.

Mike

[BDukes]

Hmm. Just a thought but has anybody thought of addressing this at the db- adjusting the WRA to 75% as the default or something like that?

Sorry to db team.

Mike

[thewood1]

First thing I do in every scenario is drop WRA to 75% on LR SAMs and AAMs.

Also note that this wouldn't help the current issue. He claims the speed is dropping at only 15nm.

[Gainful]

Basically the missiles, once the motor has burnt out are subject to the drag. The higher the missile, the less the drag, the longer the time of flight. Max range is the point it can still do a multi g manouevre to try to defeat the target, but if the target is a fighter, it will likely be less of a manouevre than the fighter can pull.

You do know that these missiles use two speeds to give the overall closure speeds.

Head on shots use the closure rate of the target as well as the speed of the missile. If the speed post burn out isnt good enough for your tactic, then why does it follow that the missile is modelled incorrectly?
I would hazard its your tactic thats wrong as the missile is following basic aerodynamic laws.

Head on, launch at around 2/3rds max range to achieve intercept at a point that gives you a second chance at a shot... shoot-look-shoot.

Tail chases, then shoot closer so the missile has a chance at running down the target, as you are subtracting target speed from your missile speed.

I'm aware of the usage of missiles with regards to head on or tail on engagements. There isn't much you can do with regards to tactics aside from setting a lower WRA range but different situations could require different approaches and the AI just isn't flexible enough to adapt to them, and you can't constantly be going in and out of the WRA screen increasing and reducing ranges for every missile and every target over and over again. I remember in older builds the AI would automatically hold off on firing if the target trajectory was away from the shooter and could decide to get closer before launching, but in recent builds its been dumbed down so they will always fire when a target is in range regardless of trajectory, which is a damn shame. Anyway, I set the WRA to use missiles at 15 nm range which is well within the max range of an aim-120-c and even then some targets coming head on managed to outrun it if they evaded immediately.

I did a couple of tests using quick battle to set up some engagements, and there is indeed some inconsistency with missile ranges and burnout times. Range is max range given in database and time is rocket motor burn time.

aa-10 alamo A - 32 nm range - 15 secs - burnout 8 nm from launch point
aa-10 alamo C - 50 nm range - 39 secs - burnout 25 nm from launch point
aim-120-C-7 - 60 nm range - 25 secs - burnout 15 nm from launch point
aa-12 adder A - 45 nm range - 37 secs - burnout 22 nm fom launch point
aa-12 adder B - 60 nm range - 56 secs - burnout 34 nm from launch point
pl-12 - 50 nm range - 8 secs - burnout 5 nm from launch point
aim-120D - 75 nm range - 1m 20secs - burnout 48 nm from launch point

Just some of the missiles I've tried out. Results differ a bit in each battle but this is about the average I've seen. In general, Russian missiles had more reasonable performance, probably because they burn out at around half their max range. You can see an aim-120c burns out much sooner than an aa-12b, which has the same range, and even an aa-10c which has lesser range. And what is up with the pl-12? Same range as the aa-10c but burns for only 8 seconds?

There was also another person on a different thread complaining about maverick missiles slowing to 150 knots or something, so yeah the missiles do need some tweaking. This is a beta after all, I wouldn't expect missile dynamics to be perfected just yet.