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PostPosted: Sat Aug 29, 2020 04:29 am 
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I have had some success at altering AI aircraft defensive maneuvers against IR threats... Instead of just dropping flares they now also brek vertically pulling the IR missile up towards the sun. So far that has worked well... I am going to see if I can get them to break hard and low against radar missile threats next... Finding my edited AI files was an amazing feat of luck... they were on a very old drive from many years ago I was scavenging for skin files...

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PostPosted: Tue Nov 24, 2020 15:12 pm 
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Although a low break vs radar missile is realistic, would it have any real effect in FA? does FA model missile energy vs altitude??


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PostPosted: Tue Nov 24, 2020 19:57 pm 
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Sounds good. It seems like during campaign play, I have to tell my wingman to maneuver while the enemy can just pop 3 chaff and continue to fly straight and level, defeating my missiles in the process.

I always figured they built in a cheat to make up for the AI enemy never using jammers.


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PostPosted: Fri Nov 27, 2020 21:41 pm 
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Vyrago wrote:
Although a low break vs radar missile is realistic, would it have any real effect in FA? does FA model missile energy vs altitude??


You can model missile's loss of energy by having reduced turn rates when unpowered and performance reductions down to sea level. Its a graduated decrease from the performance level you set at 20K ft... Lets say in this example you make a missile that has no performance reduction at 20K ft, you can set it to have a 50% reduction at sea level. It will have a fraction of that reduction for every 1K ft of altitude below 20K ft to your sea level reduction. So at 10K ft the missile has 75% of performance vs 20K Ft and if you set the unpowered turn rate to be a fraction of the power rate(again say 50%) then the missile will not only have a reduction performance as it drops after you in altitude, but if it runs out of fuel it will also have an even further reduced turn rate against you in this example...

You also have other Hit Modifiers such as Increase to performance whenG's pulled by the missile is under 3G and Decrease in performance when G's pulled are over 3G, thus adding even more limitations to the missile's performance if you jink hard and drag it down in altitude...

And an increase in performance for the missile's radar seeker if its a big target like a transport or a bomber which cant maneuver as much... You can also set the maximum G the missile can pull in the final 2000 ft before it can hit you.. So if the missile is pulling 20Gs and is within 2000 ft of you its likely going to miss if you set this limit to 20G. All my SAMs have this set to a specific limit for their final G pull as they are almost always unpowered when this occurs and if you jink hard enough you will make them miss you...

Also you can set deceleration rate when unpowered and make it respond to gravity when unpowered and set it to compute target lead so its not always a tail chaser. I just recently discovered this option and enabled it for my SAMs so they now fly a lead intercept... But it only works if you set the guidance correctly or else the missile will not function.

Also you can add Doppler parameters so the missile is vulnerable to "notching" by making a whole where the missile can not locate you if you fly perpendicular to its trajectory at sufficient range. This needs to be set to correctly mimic "notching" to be used against an AI bandit or it will track you with its weapon's seeker head if it loses you with its own radar...

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PostPosted: Fri Nov 27, 2020 21:48 pm 
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usnraptor wrote:
Sounds good. It seems like during campaign play, I have to tell my wingman to maneuver while the enemy can just pop 3 chaff and continue to fly straight and level, defeating my missiles in the process.

I always figured they built in a cheat to make up for the AI enemy never using jammers.


The effectiveness of the 3 chaff setting all depends on what level of effect you give chaff on your missile. You can set this in the FATK for your missile. My AIM-120s defeat most chaff. It will help to make it miss you if you drop quite a few, coupled with distance, dragging it down in altitude, and using ECM to defeat it, but it isn't easy. In real life chaff has very little effect against a Slammer... The big limiter is distance and whether the target realizes they are under attack and drags the missile down to sea level...

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PostPosted: Sat Jul 17, 2021 16:54 pm 
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CAG Hotshot wrote:
You can model missile's loss of energy by having reduced turn rates when unpowered and performance reductions down to sea level. Its a graduated decrease from the performance level you set at 20K ft... Lets say in this example you make a missile that has no performance reduction at 20K ft, you can set it to have a 50% reduction at sea level. It will have a fraction of that reduction for every 1K ft of altitude below 20K ft to your sea level reduction. So at 10K ft the missile has 75% of performance vs 20K Ft and if you set the unpowered turn rate to be a fraction of the power rate(again say 50%) then the missile will not only have a reduction performance as it drops after you in altitude, but if it runs out of fuel it will also have an even further reduced turn rate against you in this example...

You also have other Hit Modifiers such as Increase to performance whenG's pulled by the missile is under 3G and Decrease in performance when G's pulled are over 3G, thus adding even more limitations to the missile's performance if you jink hard and drag it down in altitude...

And an increase in performance for the missile's radar seeker if its a big target like a transport or a bomber which cant maneuver as much... You can also set the maximum G the missile can pull in the final 2000 ft before it can hit you.. So if the missile is pulling 20Gs and is within 2000 ft of you its likely going to miss if you set this limit to 20G. All my SAMs have this set to a specific limit for their final G pull as they are almost always unpowered when this occurs and if you jink hard enough you will make them miss you...

Also you can set deceleration rate when unpowered and make it respond to gravity when unpowered and set it to compute target lead so its not always a tail chaser. I just recently discovered this option and enabled it for my SAMs so they now fly a lead intercept... But it only works if you set the guidance correctly or else the missile will not function.

Also you can add Doppler parameters so the missile is vulnerable to "notching" by making a whole where the missile can not locate you if you fly perpendicular to its trajectory at sufficient range. This needs to be set to correctly mimic "notching" to be used against an AI bandit or it will track you with its weapon's seeker head if it loses you with its own radar...


Have you found a way to calculate turn rate for SAMs?
The defaults for FA are pretty off and I've been able to find, largely, what missiles can do as a max.
However converting that into turn rates in the FATK has been a bit troublesome.

In past I just used that # so if a missile could turn at 18g I put 18 in there.
However, I think I am understating their agility since in the FATK this # is degrees per second.

I've found some formulas online for converting but I don't really get useful values.
Based on documents I see a rate of turn formula being: (1091 * tan(bank angle))/velocity in kts

So for Mach 4 turning at 90 degree bank angle. I get -0.94 so clearly I'm doing something incorrect but that being said even this formula doesn't seem to give me good data when I look at what few charts I can see.

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PostPosted: Sun Jul 18, 2021 17:07 pm 
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Centurian57_369th wrote:
CAG Hotshot wrote:
You can model missile's loss of energy by having reduced turn rates when unpowered and performance reductions down to sea level. Its a graduated decrease from the performance level you set at 20K ft... Lets say in this example you make a missile that has no performance reduction at 20K ft, you can set it to have a 50% reduction at sea level. It will have a fraction of that reduction for every 1K ft of altitude below 20K ft to your sea level reduction. So at 10K ft the missile has 75% of performance vs 20K Ft and if you set the unpowered turn rate to be a fraction of the power rate(again say 50%) then the missile will not only have a reduction performance as it drops after you in altitude, but if it runs out of fuel it will also have an even further reduced turn rate against you in this example...

You also have other Hit Modifiers such as Increase to performance whenG's pulled by the missile is under 3G and Decrease in performance when G's pulled are over 3G, thus adding even more limitations to the missile's performance if you jink hard and drag it down in altitude...

And an increase in performance for the missile's radar seeker if its a big target like a transport or a bomber which cant maneuver as much... You can also set the maximum G the missile can pull in the final 2000 ft before it can hit you.. So if the missile is pulling 20Gs and is within 2000 ft of you its likely going to miss if you set this limit to 20G. All my SAMs have this set to a specific limit for their final G pull as they are almost always unpowered when this occurs and if you jink hard enough you will make them miss you...

Also you can set deceleration rate when unpowered and make it respond to gravity when unpowered and set it to compute target lead so its not always a tail chaser. I just recently discovered this option and enabled it for my SAMs so they now fly a lead intercept... But it only works if you set the guidance correctly or else the missile will not function.

Also you can add Doppler parameters so the missile is vulnerable to "notching" by making a whole where the missile can not locate you if you fly perpendicular to its trajectory at sufficient range. This needs to be set to correctly mimic "notching" to be used against an AI bandit or it will track you with its weapon's seeker head if it loses you with its own radar...


Have you found a way to calculate turn rate for SAMs?
The defaults for FA are pretty off and I've been able to find, largely, what missiles can do as a max.
However converting that into turn rates in the FATK has been a bit troublesome.

In past I just used that # so if a missile could turn at 18g I put 18 in there.
However, I think I am understating their agility since in the FATK this # is degrees per second.

I've found some formulas online for converting but I don't really get useful values.
Based on documents I see a rate of turn formula being: (1091 * tan(bank angle))/velocity in kts

So for Mach 4 turning at 90 degree bank angle. I get -0.94 so clearly I'm doing something incorrect but that being said even this formula doesn't seem to give me good data when I look at what few charts I can see.


You have to reduce the turn rate and increase the drag and decrease the number of G a missile can pull by an exponential factor below 20K feet to replicate the effects of denser atmosphere. Unfortunately there is no formula. You have to test it out manually after changes to see if you can out maneuver the missile at lower altitude if its possible to do so in the real world.

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PostPosted: Wed Jul 28, 2021 20:20 pm 
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So more or less - just to summarize - in order to increase realism:

- Performance modifier at S/L to reduce from 100%
- Lower turn rate when unpowered
- Increase drag (where is this option? or is it done via #1 above)


I think I'm going to start out testing some SAMs and try some turn rates maybe 2x the turn maximum G I found (as a starting point) and then work up/down from there since I'm really just starting from scratch.

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PostPosted: Fri Jul 30, 2021 01:03 am 
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Why would you increase the turn rate to twice the maximum G? The Max G means that the missile can not exceed that G no matter its energy due to its design...

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PostPosted: Fri Jul 30, 2021 10:10 am 
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CAG Hotshot wrote:
Why would you increase the turn rate to twice the maximum G? The Max G means that the missile can not exceed that G no matter its energy due to its design...


In the FATK the turn rate is deg / sec I haven't been able to convert from max G to deg / sec.
That's what started my post there. I think the turn rates are too low using this method.

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PostPosted: Wed Aug 04, 2021 23:38 pm 
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Centurian57_369th wrote:
CAG Hotshot wrote:
Why would you increase the turn rate to twice the maximum G? The Max G means that the missile can not exceed that G no matter its energy due to its design...


In the FATK the turn rate is deg / sec I haven't been able to convert from max G to deg / sec.
That's what started my post there. I think the turn rates are too low using this method.


SAMs have low turn rates because they are traveling so fast with small aerodynamic surfaces. Their inertia tends to continue to carry them forward when attempting a high G turn... This is how aircraft can outmaneuver them. Keep that in mind when building a SAM unless its a close range IR missile as they're usually based off of air to air missiles that have high turn rates, especially if vector thrust is used...

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PostPosted: Tue Oct 12, 2021 08:05 am 
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CAG Hotshot wrote:
You have to reduce the turn rate and increase the drag and decrease the number of G a missile can pull by an exponential factor below 20K feet to replicate the effects of denser atmosphere. Unfortunately there is no formula. You have to test it out manually after changes to see if you can out maneuver the missile at lower altitude if its possible to do so in the real world.


All right wound up doing some testing on this too last night. Push comes to shove, I used DCS as a model and in DCS I found a video someone posted of defensive maneuvering to drag missiles down but unlike most of them it went into more of the science of it versus just the maneuvers. It even included a little chart of DCS ranges of missiles. What DCS does is simply match air density. At 20,000 feet vs. sea level, the air is 54% less dense. Comparing ranges on that chart you see that at sea level, the missile has 46% the range it does at 20,000 feet. Simple enough really. So I'm going to use 46 for a sea level modifier and 100 for 20K.

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PostPosted: Wed Oct 13, 2021 06:22 am 
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Centurian57_369th wrote:
CAG Hotshot wrote:
You have to reduce the turn rate and increase the drag and decrease the number of G a missile can pull by an exponential factor below 20K feet to replicate the effects of denser atmosphere. Unfortunately there is no formula. You have to test it out manually after changes to see if you can out maneuver the missile at lower altitude if its possible to do so in the real world.


All right wound up doing some testing on this too last night. Push comes to shove, I used DCS as a model and in DCS I found a video someone posted of defensive maneuvering to drag missiles down but unlike most of them it went into more of the science of it versus just the maneuvers. It even included a little chart of DCS ranges of missiles. What DCS does is simply match air density. At 20,000 feet vs. sea level, the air is 54% less dense. Comparing ranges on that chart you see that at sea level, the missile has 46% the range it does at 20,000 feet. Simple enough really. So I'm going to use 46 for a sea level modifier and 100 for 20K.


The reduction at sea level and the gravity effects are all you can do to try to simulate this in FA... It might work. It might not. I don't think anyone has really tried to get them as close to real as possible... well "real" as in publicly released data on how they are supposed to work...

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PostPosted: Wed Oct 13, 2021 08:20 am 
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Yeah this is more horseshoes & hand grenades territory, just gotta be close.

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