How much terrain masking time required to break lock of an Aim 120

[darkman222]

I had this encounter you can watch in the video. You can see the view of the Aim 120...

An Aim 120 was fired on a MP server on me. I was terrain masking for 3 seconds. But the Aim 120 seeked just picked me up again, or it never lost me.

Although I know that 3 seconds terrain masking is very short and the seeker might do some interpolations like the radar of an aircraft like the F16 does, when it loses sight to the target. But how long is sufficient to break the lock?

And, more important. If I terrain mask, but reappear in the sight of the Aim 120 seeker, will it re-aquire me? Will it go back to a maddog state? Which means losing lock, going back to mad dog, and aquire the next visible target again? Or will the AIM 120 only go mad dog once and should not re aquire any targets after it lost the initial lock?

 

In case someone is interested. Here is the (very long) track file:

https://www.dropbox.com/s/2v7f7398s58yrjt/mobettameta's Dogfight Arena v1.29-20220106-000045 amraam terrain mask.trk?dl=0

I disconnected right after that. So its at the very end of the track file.

Edited January 7, 2022 by darkman222

[darkman222]

...well since this thread was moved to "weapons bugs" I assume it was not realistic that the AIM120 was still keep tracking me after I reappeard behind the mountain. Although that does not answer the question how long is long enough to break an AIM120 lock, it gives me some hint to the answer to my question.

Edited January 7, 2022 by darkman222

[GGTharos]

Upon watching the video again I'm not sure it's tracking you at all after you break lock, it's merely biased to continue with the same g as before, which is exactly the technique a pilto would use to track his nose onto you if he loses visual for a short time.  This is evidenced by the little 'jerk' when it locks onto you again.

So to answer your question ... you had already broken the lock and it racquired..  If you want the missile not to hit you stay out of its sight until it passes.

Maybe there's a bug hiding somewhere in there but I certainly do not see it.

 

PS:  It's not going to go 'mad dog' after losing track.  'Mad Dog' is specifically the case where the missile is launched without target data to begin with.   So on break-lock for the seeker it goes into whatever its search mode says it should do and likely tries to recover a target matching last seen target parameters as much as possible (speed, closure, direction) ... you're not doing anything to be out of those parameters, not that you could do anything like that at the short distance this missile was launched.

Edited January 8, 2022 by GGTharos

[Csgo GE oh yeah]

Also tacview ... I see people go underground for 5 seconds quite often like they are submarines. 

If i had to guess , either tacview has the mountain not quite right or some desync was happening. 

[BIGNEWY]

6 minutes ago, Csgo GE oh yeah said:

Also tacview ... I see people go underground for 5 seconds quite often like they are submarines. 

If i had to guess , either tacview has the mountain not quite right or some desync was happening. 

if its online it will be desync caused by a bad connection either on the server or the client

 

regarding the issue, as mentioned above by others I dont think there is a bug here, the missile had already lost its lock from the looks of it. 

Thanks

[okopanja]

One more possible explanation: the missile probably never lost you. The terrain in tacview is not 100% accurate to the terrain in DCS. There are sections of the map where you will fly very low in DCS, but appear to be flying below the terrain level in Tacview.

Given the fact that you barely went just below that ridge, it is very likely that the missile had you in site all the time, or lost you for even shorter period then what tacview lets you to believe.

I would suggest watching your track view to really determine if there was line of site.

 

[dorianR666]

i dont see any issue in the video

 

if the missile loses sight of you, it will guide as if you continued the flight like the last moment it saw you, and reacquire once it sees you again.

Edited January 14, 2022 by dorianR666

[borchi_2b]

So, all I seeon my phone watching the video, is an amraam chasing a target with an already cold aspect at a relativly high altitude in a valley. Just because there is a mountain somewhere in the far background does not imply that a self homing missile will loose guidance or that you suddenly disappear in a ground clutter. The distance to the ground will also determine the ammount of noise. The monopulse radar of the aim120c has a range of 12 to 16km / 6 to 8nm, depends on the puplic source. The further you are from the "wall" and the less the noise, the better the monopulse will be able to compute your position. 

A 3 second turn below the horizon will not help you, esspecially when you are a clear distictable target on a cold aspect. 

Using groundclutter and notch against modern medium range missiles as effective defense is a myth, which any RL fighter pilot will tell you is wrong. 

There is only 2 ways against bvr missiles since the mid 90ties. outrun or outturn/outenergy the missile. 

notch/chaff/groundclutter filters are parts of the systems avionics and software, which are values the engeneers can compute and have done. Maneuvers are something they can only predict and modern missiles only have x ammount of kinetic energy, exempt the meteor that runs on a engine and will adjust its speed all the time for a perfect intercept as long it has fuel, after thier motor burned out at x altitude, which is something pilots can work with. 

But keep in mind, RL does not have a replay button. Most likely pilots will not react to missiles like the gamers do for many reasons. 

That said, to defend against the missile in your video, you have to be waaaay lower, maneuver a lot more and put a ton of chaffs into the air. 

Ohh and if you had the feeling, you did defeat the missile, because your rwr stopped talking to you, all rwr systems have a rwr gimbal limit. If you exceed the angle between the radar threat and your rwr will it go silent after x seconds and will also need a certain time to refresh, even though the radarthreat might be back in the gimbal limits. 

 

Happy fighting