Question Regarding Missiles

[S77th-GOYA]

I've been trying to locate the thread where someone in the know says that a different radar painting a target fired on in HOJ is not likely to keep the missile tracking. No luck so far. But even if you are correct, a HOJ shot would still only be conditionally fire and forget because an outside element is still required.

 

Which reminds me, I was in the same TS channel as an enemy Su-25T recently and I heard him report being locked when I locked his jam in my F-15. I thought F-15 radars were not supposed to give a warning of lock or launch in HOJ mode.

 

That would be correct.

 

This track shows that 1.12a is not modeled that way.

JamWarning.zip

[Kuky]

What if you fire SAR missile in HOJ and target switches it ECM off then turns it on again... will/should the missile reacquire lock onto jamming signal again?

[D-Scythe]

What is you fire SAR missile in HOJ and target switches it ECM off then turns it on again... will/should the missile reacquire lock onto jamming signal again?

 

The real AMRAAM uses both HOJ and active radar for terminal guidance - what I don't know if these two modes are used alternate each other in a sequence (e.g. active radar, HOJ, active radar, etc.) or somehow in combination (both at the same time). In any case, something as simple as manually (NOT considering automated jammers right now) turning the jammer on and off is unlikely to fool an AMRAAM - or the Sparrow, for that matter, so long as the aircraft that launched it kept its lock.

 

Automated jammers are trickier because they can choose to only emit when the missile is in active radar mode - thus if the AMRAAM is alternating between HOJ and active radar guidance it would be fooled. On the other hand, the AMRAAM's seeker can emit while HOJ (like the N001/019 radars on Flanker/Fulcrum), thus ensuring that the jammer is always emitting. It might even be possible that the AMRAAM's software permits it to employ both emitting and non-emitting HOJ techniques - non-emitting if the jammer is dumb enough to always be "on" and thus achieve the silent kill, or switching to emitting when it's been found.

 

I suspect this situation to be a lot more complicated with Sparrow, since the APG-63/70 is silent when in HOJ mode.

 

I'd expect Russian missiles to behave in much the same way.

 

But even if you are correct, a HOJ shot would still only be conditionally fire and forget because an outside element is still required.

 

No reason why the AMRAAM cannot emit while it's HOJ, ensuring the SPJ is continually active.

[S77th-GOYA]

No reason why the AMRAAM cannot emit while it's HOJ, ensuring the SPJ is continually active.

 

Using a fire and forget missile to demonstrate that HOJ is fire and forget? Nobody limited any of this HOJ discussion to ARH missiles. Consider a Sparrow and the term "conditionally" still applies. Besides that, the 120 (ingame) still doesn't go active until the same ~7-8nm range if fired in HOJ. Do you have any data showing that it goes active farther away in the real world?

[D-Scythe]

Using a fire and forget missile to demonstrate that HOJ is fire and forget? Nobody limited any of this HOJ discussion to ARH missiles.

 

Nobody limited this discussion to SARH missiles either. The first poster said this, "I am wondering if a missile fired in Home on Jam mode requires that I maintain a lock on the target, or if a missile fired in this mode is fire and forget e.g. can I break lock after firing a missile in HOJ mode and still expect it to guide, or do I have maintain a constant lock on the target as if I was firing a SARH missile. Note that I am asking in regards to LOMAC FC 1.12a."

 

I assumed he was talking about all radar missiles.

 

Consider a Sparrow and the term "conditionally" still applies.

 

Clearly.

 

Besides that, the 120 (ingame) still doesn't go active until the same ~7-8nm range if fired in HOJ. Do you have any data showing that it goes active farther away in the real world?

 

No. But there's isn't any data pertaining to ECM vs. ECCM anyway, even if you go back 30 years. Consider an AIM-120 is fired, and it's ropes are cut right away as the F-16 that launched it breaks away. Does the AMRAAM turn on its radar right away, or does it fly to its "activation point" and then turn on its radar? If the answer is the latter, what if the both the AIM-120 and the F-16 were tracking the target HOJ, so there was no activation point? Then would the AMRAAM radar start HOJing/emitting to reacquire the out-of-range target, on the off chance that it's radar energies might be enough to activate the SPJ? Or does it just do nothing?

[GGTharos]

Searching begins at 13nm against a fighter-sized target (lock on might not happen until later), from HUD-tape and IIRC MLU manual. As far as the real thing goes anyway - none of this is answering the OP's question though ...

 

Using a fire and forget missile to demonstrate that HOJ is fire and forget? Nobody limited any of this HOJ discussion to ARH missiles. Consider a Sparrow and the term "conditionally" still applies. Besides that, the 120 (ingame) still doesn't go active until the same ~7-8nm range if fired in HOJ. Do you have any data showing that it goes active farther away in the real world?

[GGTharos]

An SPJ will attempt to reproduce the signal that's being thrown at it; as such, it reproduces the same thing a missile would home on to. If there's no incoming signal, there is no reason to transmit.

IIRC the Sorbitsya, or was it Gardenya - was advertized as having a 5 sec jamming cycle followed by a 3 sec listening cycle to see if it broke the lock.

 

Similarly a missile switching to HoJ might 'entice' the SPJ to transmit back a certain type of signal and make its homing deadlier than a missile that would simply switch to PN at that time.

 

A missile launched in HoJ will likely go PN right away (something we do not see in LO because 1) HoJ missiles go pure, 2) LO missiles go PN straight away instead of restricting g for the long haul), thus reducing its effective range. There are ways of getting around this, but in general it lowers the missile Pk because of this or that reason.

 

This leads us to the question: 'Why not jam all the radars, just like in LO?'

Because an SPJ has limited processing and trasmitting power, and a limited amount of time to do all this jamming in. Therefore will exclusively jam threat radars, meaning radars that have locked onto it.

Further, an SPJ can only jam the n top threats, where n is not a very large number. This means attempting to jam 4 F-15's in TWS mode will leave you vulnerable to AMRAAM missile seekers, as the F-15's will typically transmit slightly different signals from each others (As an example).

 

So you have to be pretty picky about what you define as 'threat'.

 

No. But there's isn't any data pertaining to ECM vs. ECCM anyway, even if you go back 30 years. Consider an AIM-120 is fired, and it's ropes are cut right away as the F-16 that launched it breaks away. Does the AMRAAM turn on its radar right away, or does it fly to its "activation point" and then turn on its radar? If the answer is the latter, what if the both the AIM-120 and the F-16 were tracking the target HOJ, so there was no activation point? Then would the AMRAAM radar start HOJing/emitting to reacquire the out-of-range target, on the off chance that it's radar energies might be enough to activate the SPJ? Or does it just do nothing?

[Snowcat]

and there are ways of ranging your target (which the radar should do ANYWAY despite the jamming - but not modeled in LO)

 

Yeah & I have to this day still not worked out to do that. Any hints:music_whistling:;):helpsmilie:

[GGTharos]

Basic trig ;)

[D-Scythe]

Yeah & I have to this day still not worked out to do that. Any hints:music_whistling:;):helpsmilie:

 

You can't in Lock On.

[Snowcat]

Basic trig ;)

 

Trig never was my strong point:joystick:

[GGTharos]

Come on, do a little work! You'll find it rather easy.

[Snowcat]

Maybe if i was a mad scientist may be, but it has been 26yrs since I left school & have never needed trig for driving a truck so the old grey matter didn't retain that stuff.:smartass::pilotfly::joystick:

[Pilotasso]

You drive a truck?

 

Picture your going to pass under a bridge, judging the distance to the bridge and the angle of your head when your looking directly at it, you can estimate whether your cargo troley is going to pass under it or be smashed... :D

 

So be carefull assuming your not going to need it. :rolleyes:

[D-Scythe]

You drive a truck?

 

Picture your going to pass under a bridge, judging the distance to the bridge and the angle of your head when your looking directly at it, you can estimate whether your cargo troley is going to pass under it or be smashed... :D

 

So be carefull assuming your not going to need it. :rolleyes:

 

That's not trig, that's just gauging distance with your eyes. I doubt your mathematically working the numbers and angles in your head.

 

And this is a truck. Supersonic aircraft typically move a lot faster - increases error.

[GGTharos]

You can typically ballpark an aircraft to +/- 3nm at 40 nm or so using basic rules of thumb (derived from trig); it requires some extra maneuvering and getting used to doing some of this math in your head, but it's actually not hard at all.

[HubMan]

...

Besides that, the 120 (ingame) still doesn't go active until the same ~7-8nm range if fired in HOJ. Do you have any data showing that it goes active farther away in the real world?

Hi guys :) Just a little precision :

 

Fox 3 are detected in Lockon by the RWR / SPO once they are at ~8nm/~15km from their target and they get "pitbull" (MPRF).

 

But the missiles are autonomous as soon as ~12nm/~22km as they are "husky" (HPRF) and do need any support at this points from the launching aircraft... :)

 

It seems to be a fair simulation of the real world missile guidance general principles :)

 

 

 

Cheers :)

 

 

Hub.

[GGTharos]

Now all we need is the 700-1000kts of missing top speed on that 120 and we're set!

[HubMan]

Now all we need is the 700-1000kts of missing top speed on that 120 and we're set!

Almost set :) I would add (if it has not been done already) :

 

- modelization of the mach "hump" (firing missiles from a supersonic aircraft should give a better range) and lofted profile (less drag) to get a chance to score hit with a fair PK at 20nm.

 

- decent seeker that does not bite on chaff that easily and less prone to be abused by notch manoeuver. That would put some realism in BVR fights (the hightest / fastest the best) as having to fire Fox 3 in -look up- is a joke

 

- R-77 for the Su-27 and/or no RWR warning upon launch for russian's Fox 1. As a realistic AMRAAM would be no fun otherwise... :P

 

Cheers :)

 

 

Hub.

[GGTharos]

Almost set :) I would add (if it has not been done already) :

 

- modelization of the mach "hump" (firing missiles from a supersonic aircraft should give a better range) and lofted profile (less drag) to get a chance to score hit with a fair PK at 20nm.

 

I think we will have a better chance of simply adding the aircraft's mach number to the missile's top speed ... what you are suggesting I would like to see, but I suspect it may be too much of a bother to model for a LO patch. :(

Has been mentioned, but not a lot.

 

 

- decent seeker that does not bite on chaff that easily and less prone to be abused by notch manoeuver. That would put some realism in BVR fights (the hightest / fastest the best) as having to fire Fox 3 in -look up- is a joke

 

Absolutely, totally, completely agreed - yes, it has been mentioned.

 

- R-77 for the Su-27 and/or no RWR warning upon launch for russian's Fox 1. As a realistic AMRAAM would be no fun otherwise... :P

 

Cheers :)

 

 

Hub.

 

 

No R-77's for any Russian aircraft would be more correct actually ;)

But in any case yes, you're right; the 'missile warning' needs to go since apparently all you'll get these days is a lock on warning and nothing else.

[HubMan]

I think we will have a better chance of simply adding the aircraft's mach number to the missile's top speed ... what you are suggesting I would like to see, but I suspect it may be too much of a bother to model for a LO patch. :(

...

I think modelization of the launching aircraft being over the mach could be kept to something simple...

Like increasing the missile top speed by some "bonus" if fired over the mach. The bonus could be a simple function of the launcher speed, equal to 0 for mach 1, reaching its maximum and becoming constant for something like mach 1.8. A couple of linear functions would be dirty (no need to do an interpolation with a sophisticated function), but would do the trick... :)

 

Cheers :)

 

Hub.

 

PS : I agree with the R-77 within the time frame of Lockon :) But in this case, AIM-120C should be AIM-120A (ie not almost immune to notch) otherwise, the game would lose it's "balance" :)

[GGTharos]

I see HUbMan ... are you saying we should do this ...

Right now, we have: Missile top speed (hardcoded) for example, for sidewinder it is 2.5M

 

According to you, we should have:

Missile top speed + Aircraft Mach number + bonus for launch over mach?

 

Also, a quick and dirty thing: Use something like a (sine/cosine function * some number) = modifier, then have this modifier added to the drag for the missiles for going UP, and subtracted for going DOWN ... actually you'd need two functions, one for going up, one for going down ... that way you would penalize a climbing missile and thus you would once more have a reason to make BVR more realistic, by making fighters want to gain altitude (and obviously speed with the above) for range!

 

I agree with you about the specific missile models. Right now, although we call it a -C, it's far worse than an A :D

[Pilotasso]

You drive a truck?

 

Picture your going to pass under a bridge, judging the distance to the bridge and the angle of your head when your looking directly at it, you can estimate whether your cargo troley is going to pass under it or be smashed... :D

 

So be carefull assuming your not going to need it. :rolleyes:

That's not trig, that's just gauging distance with your eyes. I doubt your mathematically working the numbers and angles in your head.

 

And this is a truck. Supersonic aircraft typically move a lot faster - increases error.

 

 

 

LOL dude, that was just a joke, wasnt meant to be taken literaly. :D

[D-Scythe]

I think modelization of the launching aircraft being over the mach could be kept to something simple...

Like increasing the missile top speed by some "bonus" if fired over the mach. The bonus could be a simple function of the launcher speed, equal to 0 for mach 1, reaching its maximum and becoming constant for something like mach 1.8. A couple of linear functions would be dirty (no need to do an interpolation with a sophisticated function), but would do the trick... :)

 

A linear relationship would be a mistake - almost nothing in this world scales proportionally. Simply adding the aircraft's speed to the missile speed is too radical of a solution, without any realistic fact to back it up except "missiles fired from higher speeds go faster." Well, nobody said the increase in missile speed scales in a linear fashion to increases in launch speed.

 

In fact, I know it doesn't - drag increases exponentially as speed increases.

 

PS : I agree with the R-77 within the time frame of Lockon :) But in this case, AIM-120C should be AIM-120A (ie not almost immune to notch) otherwise, the game would lose it's "balance" :)

 

This is a simulation - balance should take the backseat to realism every single time. There are other ways to "balance" the game without implementing totally incorrect and absolutely meaningless "fixes" - for one, the players themselves could just simply adjust their tactics to overwhelm the F-15s by numbers.

[GGTharos]

A linear relationship would be a mistake - almost nothing in this world scales proportionally. Simply adding the aircraft's speed to the missile speed is too radical of a solution, without any realistic fact to back it up except "missiles fired from higher speeds go faster." Well, nobody said the increase in missile speed scales in a linear fashion to increases in launch speed.

 

In fact, I know it doesn't - drag increases exponentially as speed increases.

 

It doesn't matter; adding the mach number is a very simple, elegant, and acceptable solution requiring MINIMAL work ... asking for complex formulae ensures we won't see anything of the sort in the patch.

 

This is a simulation - balance should take the backseat to realism every single time. There are other ways to "balance" the game without implementing totally incorrect and absolutely meaningless "fixes" - for one, the players themselves could just simply adjust their tactics to overwhelm the F-15s by numbers.

 

 

Lock On can be a simulation, depending on how you use it. It simulated flight nicely enough, but certainly not BVR. In that respect it is not a simulation.