Missile range and altitude.

[FoxZz]

Hello,

Currently ingame, the air-to-air missile range always stays the same at any altitude and speed, however, this is not the same in real life.

Indeed, IRL, the Missile range decrease greatly when the plane lower its altitude, due to the higher air density which causes more drag and thus higher fuel consomption and degrade energy fatser.
In the same manner, flying fast prior missile release will give the missile more initial energy and will allow him to reach a greater distance.
Also, shooting from a higher position will give the missile more energy while shooting from a lower one will achieve the opposit result.
That's why in BVR combat, reaching first max altitude and max speed is critical to shoot down the opponent. Consequently, Interceptors are often designed to reach high speeds, high altitudes and high rate of climb.

I would like to know if such a feature could be included ? (Missile range changing with A/C speed and altitude and PH changing with altitude differencies between A/C).

Thanks for considering this (maybe it has already been considered ?).


PS : Also, as a side note, this is why I think A/C max speed and altiude should not be that standardised, as it completly negates the aircrafts dynamics differencies, and make an AMRAAM armed Harrier as good as an AMRAAM armed Typhoon.
I know that in peace time the Aircrafts rarely reach their max speed, but in war time and in air to air combat exercices, they do. Moreover, the airplanes flight enveloppe already includes speed limitations to protect the aircraft, and I don't think an additional game limitation is needed. For example, the Rafale max speed is 1.8 mach even though is could largely go beyond mach 2, same thing for the Typhoon, that is limited at mach 2 but can go above this speed. Maybe the aircraft could get their official max altitude and speed implemented, with some tweeks to make it on pat with reality.

[cdcool]

I agree on both

[Dimitris]

ORIGINAL: FoxZz

Hello,

Currently ingame, the air-to-air missile range always stays the same at any altitude and speed, however, this is not the same in real life.

This is incorrect. We do model different missile speeds & ranges per altitude. If you perform a number of launches from different altitudes and speeds you will observe this.

What _is_ abstracted ATM, is that the _maximum_ per-altitude missile speed is the same regardless of initial speed at that altitude. So for example an AMRAAM launched from a subsonic Harrier and one launched from a supercruising F-22 will both reach Mach 4 eventually (however, the latter _will_ travel further as it will have spent slightly more time at high speed than the former). In an equivalent RL setup the effective range difference will be more profound because the latter missile will also enjoy a higher maximum speed.

This is one of the limitations in our current kinematic model. We have something more advanced in the works but it is a future item.

[Dimitris]

PS : Also, as a side note, this is why I think A/C max speed and altiude should not be that standardised, as it completly negates the aircrafts dynamics differencies, and make an AMRAAM armed Harrier as good as an AMRAAM armed Typhoon.

See above. We model this.

I know that in peace time the Aircrafts rarely reach their max speed, but in war time and in air to air combat exercices, they do.

Q: What was the maximum "at weapon launch" speed of the USAF F-15s during all of the AIM-7 BVR engagements in Desert Storm?

A: Just over 650 knots at high altitude, ie. Mach 1.13.

That's reality.

Moreover, the airplanes flight envelope already includes speed limitations to protect the aircraft, and I don't think an additional game limitation is needed.

It's not just about protecting the aircraft. It's about the theoretical speeds being attainable only if you do a record-setting flight instead of a combat sortie.

For example, the Rafale max speed is 1.8 mach even though is could largely go beyond mach 2, same thing for the Typhoon, that is limited at mach 2 but can go above this speed. Maybe the aircraft could get their official max altitude and speed implemented, with some tweeks to make it on pat with reality.

Do us a favor, will you? Go and download any of the myriad ACMI-recordings for e.g. Falcon-4 or DCS-World. Actual simulated missions, not acrobatic flights. Go through them. Write down the maximum speed any of these great fighters attained _while flown by a player that wants to accomplish a mission and survive, instead of setting a speed record_. Then come back to us with your findings.

We have discussed this, at length, with people who do this for real. That's reality. Let it go.

[FoxZz]

Sorry Sunburn, but I never noticed range differencies between missiles shot at different altitudes, and when it comes to speed, missiles travel at the same altitude and speed on most of the way independantly from the missile speed and altitude release. Maybe we're not talking about the same thing.

When you take an AMRAAM armed F16 and make it fly at low altitude, its max range will be the same than the exact same F16 at high altitude. The pink circle will have the same size and you will be able to fire a missile on any target that enters that circle head on.

What I meant is that the low altitude F16 should have a smaller ARAAM pink circle than the one at high altitude, in the same way, the slower of the two should also have a smaller pink circle. Currently, independantly from your altitude and speed, you can engage a target at max range (if this one fits in the PH calculation).
Also, the altitude differance should lower the PH or increase it, depending on the aircraft position and the missile climbing performance.

Currently, aircrafts flying at loiter speed and low altitudes have the same range than aircrafts firing at max range and high altitudes with the same missiles.

This leads to things like firing at loiter speed to lower the closing ratio, and other behaviours which are unrealistic.

I join a simple scenario that shows it : 2 typhoons, 1 at low alt, the other at high alt can engage manually two closing SU-35 at the same time and range.


PS : Ok, I understand your policy on the altitude and standardisation, even though I think it could be a little more diverse. About desert storm, the F-15 always engaged with awac support at rather close range against poorly trained and awared pilots, hence, little interest in maximizing your missile range and energy.

[Dimitris]

ORIGINAL: FoxZz
Sorry Sunburn, but I never noticed range differencies between missiles shot at different altitudes,

I did [:)]

and when it comes to speed, missiles travel at the same altitude and speed on most of the way independantly from the missile speed and altitude release. Maybe we're not talking about the same thing.

Many modern missiles, like AMRAAM and AIM-7M, follow a lofted profile (they rise to a certain high altitude in order to maximize their downrange). This reduces the effect of launch speed & altitude because the missile spends most of its flight at the same altitude (and as I explained before, at the same maximum speed).

The difference becomes more visible if you use a direct-flight weapon (no loft) like the AIM-7F or any the R-27 family. In this case you can very clearly observe the effect of launch altitude & speed on effective speed & downrange.

When you take an AMRAAM armed F16 and make it fly at low altitude, its max range will be the same than the exact same F16 at high altitude. The pink circle will have the same size and you will be able to fire a missile on any target that enters that circle head on.

The "pink circle" is the MAXIMUM NOMINAL RANGE, not the EFFECTIVE DYNAMIC LAUNCH RANGE which is what we use for pre-fire checks.

What I meant is that the low altitude F16 should have a smaller ARAAM pink circle than the one at high altitude, in the same way, the slower of the two should also have a smaller pink circle.

1) If the "pink circle" represented the DLZ instead of the theoretical range, you would need to spend a serious chunk of CPU cycles in order to dynamically expand/contract the ring as the map refreshes. Hint: DLZ calculations are one of the most CPU-expensive things in the sim code.

2) Even if it was a cheap operation, it would still be meaningless for the simple reason that the DLZ is different for each target. If you have e.g. a fast incoming target and a receding one, you'd have to draw two different rings to show the DLZ against each. Now try visualizing this on a simple 10v10.

Are you sure you're thinking this through?

Currently, independantly from your altitude and speed, you can engage a target at max range (if this one fits in the PH calculation).

No you can't. In fact even at optimum altitude and speed the effective launch range is almost always less than nominal (unless you're engaging e.g. an incoming MiG-25 or SR-71, or ballistic targets).

Also, the altitude differance should lower the PH or increase it, depending on the aircraft position and the missile climbing performance.

Sure, let's find some funding for that too. Because we don't have enough variables on AAW missile engagement already.

Currently, aircrafts flying at loiter speed and low altitudes have the same range than aircrafts firing at max range and high altitudes with the same missiles.

See above. Big difference between lofted and direct-flight weapons.

This leads to things like firing at loiter speed to lower the closing ratio, and other behaviours which are unrealistic.

Cranking unrealistic?! Not according to the pilots we talk with.

I join a simple scenario that shows it : 2 typhoons, 1 at low alt, the other at high alt can engage manually two closing SU-35 at the same time and range.

Let's hear it again: LOFTED AMRAAM. And I doubt it's _exactly_ the same launch range (see previous post).

(Speaking of: In the pro edition, one of the nice things is you can get readouts of the exact range-to-target at weapon launch (among other reams of data). If you're as serious about this as you try to show, contact us privately for a price quote.)

PS : Ok, I understand your policy on the altitude and standardisation, even though I think it could be a little more diverse.

Of course it could. Nothing is a poor investment of time/resources when someone else has to do it.

About desert storm, the F-15 always engaged with awac support at rather close range against poorly trained and awared pilots, hence, little interest in maximizing your missile range and energy.

Take a look at this photo:



This is an AIM-7M at the moment of impact on an Iraqi MiG-29 on January 19, 1991. The Fulcrum had locked on and was about to fire on the wingman of the F-15 that shot it down. The full story is available here: http://www.theatlantic.com/magazine/arc ... ce/307291/

It's easy to rationalize after the fact. As far as the US pilots were concerned, in the first days of the air war (majority of BVR kills against alerted fighters; the "flight to Iran" turkey shoot later was another ball game entirely) they were facing MiG-29s and MiG-25s crewed by battle-hardened, cream-of-crop veterans (some of whom, for instance the Foxbat driver that penetrated a USN package, shot down an F/A-18 and got away clean, did live up to the hype). They didn't have the slightest intention of going easy on them, and they didn't. They fought like they were trained, and they pushed their equipment to its limits. That included pushing their combat-loaded F-15Cs through the sky as fast as possible prior to launch.

[mikmykWS]

Looks like somebody has a few thousand hours playing DCS etc[:)]

Seriously though FoxZz stop trolling D.

Mike

[FoxZz]

No need to get angry, I'm not criticizing your work, I was asking if this was considered in a future update. That being said, you tell me this is already implemented. But maybe it should be enhanced in the future because I don't think it works as it should.

Indeed, even if your missile is going into a loft profile, if you fire it a low altitude, it still has to go through all the dense lower atmosphere before reaching the high altitude, which will severly reducce its energy and in the end it will loft lass far than a high altitude launched missile. Air friction causes drag, the more air you have, the more energy you have to spend. And as far as I know, both modern and ancient missiles are submitted to the laws of physics. I'm quotting wikipedia on the R77 : "For example, the Vympel R-77 has stated range of 100 km. That is only true for a head-on, non-evading target at high altitude. At low altitude, the effective range is reduced by as much as 75%–80% to 20–25 km.". That's what I'm talking about, sorry but this phenomenon is either not implemented, either greatly under-estimated. https://en.wikipedia.org/wiki/Air-to-ai ... sile_range (missile range paragraph).
And also this : http://www.x-plane.org/home/urf/aviatio ... s/aam.html

Concerning the pink circle, what I'm talking about, you're already doing it on the air to ground weapons range, the orange circle grows bigger when the aircraft gets higher and the contrary. That's what I meant. I know this is the max theorical range, even though, missiles have different max theorical range for each altitude. This would not require several circles, or target stuff nor complex calculations, it's just displaying the max theorical range of the missile at a given altitude, and a given launch speed, the later being more complicated to implement, and I would understand if you don't.

Try the scenario, and you will see that the Typhoon can engage the SU as soon as it gets in range, independantly from the altitude. There is absolutely no differencies in the weapon release permission, and when you change the SU vector, both Typhoon won't be able to fire because out of weapon DLZ, but will switch green at the exact same time when they get closer. That's why I think it could be improved. If there is a difference, it's so slim that it's not visible without your pro edition.

I never said cranking was unrealistic, I said firing at loiter speed was. Cranking is the answer to high closing speed, not slowing down, in air to air combat you need as much as energy as possible, both for energizing your missile and for the eventual merge. The cranking mecaning is good. But the fact that the player can just lower its speed should come with the disadvantages it has IRL.

I'm not criticising you, nor trolling, I'm trying to propose things that might enhance the simulation, it seems I've not been clear enough and I apologize. I'm also not saying that this situation is broken and should be resolved asap, but rather that it might be something to put on your to do list and implement it when you have time and that higher priority stuff has been done. I love this game and that's why I cannot stop thinking how it could be even better. Since I'm making those proposal in good faith, here is the way I think it could be implemented :

When I look into the armory, I can see that indeed, missiles have different speeds depending of the band, and they go trough all of them (or not) allong their pattern. However, they spend the exact same amount of fuel (which I guess is the abstraction of the missile total energy) in all the bands. The change I'm talking about is increasing the fuel spend per second in the lower bands.
Also, once the burst duration is over, they should not be able to accelerate anymore. This could be implemented by setting for each missile a burst duration which would "load" the fuel bar at a constant rate of "fuel point/sec" (linked to the missile acceleration properties), once the burst is over, the missile would begin to spend its fuel/energy available at the rate of the altitude band it's situated in.
The altitude band the missile is bursting in would impact the "loading rate". For example, if the missile load 50 fuel pt per second and the band where it is evolving reducce its fuel by 10 point every second, the missile will load only 40 fuel point per second.
The pink circle would materialise the max theorical range of the missile against a head-on target in the same band as the launcher, based on the fuel consomption stuff I just talked about and your current calcuations.
The altitude delta impact on the PH calculation could be donce by reducing the Pk by 10% each time the missile has to cross a band upwards and increase it by 10%/ or no modifier each time it cross a band downwards.
So in the end, if a missile is fired at high altitude, it would have an optimal range because it would cross less bands upwards, and would be from the start in optimal fuel band.

For now the simplest and quickest solution to resolve this precise issue would be to implement the different missiles fuel consomption values for each band. The burst stuff would be the next step.

In the same way, but this is another topic, aircraft should be more or less agile depending on the altitude bands >> the altitude band would act on the aircraft agility modifier during the hit calculations. Aircraft would have bands were their agility is nominal and others where it is degraded depanding on their design choices, but in a general manner, at high altitude they should be less agile since the lower air density degrade their lift. Missile could also get agility modifiers, some could drag more (bigger control surfaces) but have a higher agility, while the sleeker designs would spend less fuel but have worst agility. Than the hit calculation would be done by comparing the missile final agility to the aircraft final agility, if one is higher than the other, there is a hit. Basically, all the modifiers would impact the nominal agility which would replace the PH. Of course, at equal generation, the missiles would start with a higher agility than the planes. The spoofing stuff would stay as it is. But I guess this is too complicated for now to implement.

PS : Indeed, I have noted the different speed thingie on the direct flying missiles like the sparrow, even though, since they spend the same fuel in every band, this doesn't make a lot of differance in the range, even if more than the AMRAAM, however, they are still able to be shot at max range on head on target independantly from altitude.

[thewood1]

I think the devs point might to do a little more searching and less preaching. Most of this stuff has been discussed before and it would better serve the devs to spend more time implementing than justifying to someone who still seems to be learning the game.

[mikmykWS]

ORIGINAL: thewood1

I think the devs point might to do a little more searching and less preaching. Most of this stuff has been discussed before and it would better serve the devs to spend more time implementing than justifying to someone who still seems to be learning the game.

Actually he reminds me of us years ago in a galaxy far away[:)]

He needs to see the access we give though as an opportunity to get what he wants out of the game though and not an opportunity to get 5 seconds of validation on a web forum. It's one thing to know the theories but another to actually implement it in software that basically works. D is the very few people who have a proven ability to do that so it would be if Fox's best interest to not beat on him needlessly. Not just because he'll likely get more out of it in Command but he might just learn something about software development which he seems to have an interest in.

Mike

[cdcool]

ORIGINAL: thewood1

I think the devs point might to do a little more searching and less preaching. Most of this stuff has been discussed before and it would better serve the devs to spend more time implementing than justifying to someone who still seems to be learning the game.

I agree

[FoxZz]

Ok, I might have been too agressive in what I asked, and inded I did not saw all the parts of the equation. Sorry. Now, do you deny the huge part played by launching altitude and speed on the missiles PH and max range (both are linked) ?

If indeed, I can see you partly modelled the range and speed limitations linked to altitude, it's still under-modelled compared to the real life figure : about 70-80% range degradation at low altitude.

Now, I'm proposing to increase the "point of fuel spend per second" by the missile in the lower altitude bands. That's it. The aircraft fuel consomption already works like this, and it would be more accurate while statying in the curent abstraction. SO if the missile is fired or has to go through the lower bands, it will run out of energy more quickly and thus, will reducce the range significantely.
The extra would be for the player to be able to visualise the max theorical range of its missile at the current plane altitude. This could be modelled in the same way the aircraft gun range is modelled.
Than you told me that the launching speed issue was being work out for a future upgrade, so I have nothing to add on this.

So either tell me that what I'm proposing is not doable, or that you have other plans in mind to resolve this issue in a future upgrade, or that you won't adress it because x reason. That's all I'm asking.

Thanks.

[cdcool]

Fair question

[thewood1]

ORIGINAL: mikmyk

ORIGINAL: thewood1

I think the devs point might to do a little more searching and less preaching. Most of this stuff has been discussed before and it would better serve the devs to spend more time implementing than justifying to someone who still seems to be learning the game.

Actually he reminds me of us years ago in a galaxy far away[:)]

He needs to see the access we give though as an opportunity to get what he wants out of the game though and not an opportunity to get 5 seconds of validation on a web forum. It's one thing to know the theories but another to actually implement it in software that basically works. D is the very few people who have a proven ability to do that so it would be if Fox's best interest to not beat on him needlessly. Not just because he'll likely get more out of it in Command but he might just learn something about software development which he seems to have an interest in.

Mike

Looking at his last post...I'm betting he doesn't get it. Sometimes people ask for an answer. They don't think no is an answer and keep asking. But "no" is an answer...even if its said i na different way.

[thewood1]

ORIGINAL: FoxZz

Ok, I might have been too agressive in what I asked, and inded I did not saw all the parts of the equation. Sorry. Now, do you deny the huge part played by launching altitude and speed on the missiles PH and max range (both are linked) ?

If indeed, I can see you partly modelled the range and speed limitations linked to altitude, it's still under-modelled compared to the real life figure : about 70-80% range degradation at low altitude.

Now, I'm proposing to increase the "point of fuel spend per second" by the missile in the lower altitude bands. That's it. The aircraft fuel consomption already works like this, and it would be more accurate while statying in the curent abstraction. SO if the missile is fired or has to go through the lower bands, it will run out of energy more quickly and thus, will reducce the range significantely.
The extra would be for the player to be able to visualise the max theorical range of its missile at the current plane altitude. This could be modelled in the same way the aircraft gun range is modelled.
Than you told me that the launching speed issue was being work out for a future upgrade, so I have nothing to add on this.

So either tell me that what I'm proposing is not doable, or that you have other plans in mind to resolve this issue in a future upgrade, or that you won't adress it because x reason. That's all I'm asking.

Thanks.

Might I suggest, since you've been schooled a little on making demands, that if you are serious about a change, put the request in the feature request thread.

[FoxZz]

Ok, I've done it.