wip AIM-120 Guidance When Not Supported

[nighthawk2174]

So something that appears to be 100% replicable is that in the F15 if you fire off an AMRAAM and don't provide continuous tracking up to impact the missile will go ballistic:

 

track 1 - TWS till impact

track 2 - Snipped tracks

 

High alt shots here when I get more time I'll do this at more altitudes with more jets.  Just no time right now.

TWS_SNIPPED.acmi TWS_TO_IMPACT.acmi

[NoJoe]

I'm seeing mostly the same in the Hornet.  If I turn the radar to SIL (or turn around so I'm facing the other way), the AMRAAM appears to initially loft normally, but it just keeps going up and up; it isn't continuing the loft trajectory to come back down to the target's initial calculated intercept point. 

 

It "feels" like this is the same issue as with the F-15.

 

Track attached.  I launch at long range on a MiG, and let the AMRAAM start its loft.  Then I turn the radar to SIL.  The AMRAAM never comes back down; it just appears to be trying to continue upwards.  (I ended up launching a second AMRAAM at the target later at a closer range.  I turned the radar to SIL before it went active, but it was a straight enough shot that it was able to go active and find the target on its own.)

 

Expected result:

I would expect the AMRAAM to loft itself up and back down to the initial calculated intercept point of the target, before the radar track was lost (?).

 

And my apologies if I'm piling onto what ends up actually being a separate issue.

 

Hornet AMRAAM loss of track test.trk

 

[EDIT] Oh nuts, I'd missed this other thread.  I think my post is the same issue as this other thread: 

 

Edited December 19, 2020 by NoJoe

[nighthawk2174]

No seems like its the same issue and is kind of a big one.

[Gripen 4-1]

+1

same

[dorianR666]

confirmed

[nighthawk2174]

Yeah so basically the behavior we should be seeing is the missile continues to loft towards the predicted intercept point.  Going in to the terminal phase about 8NMi or so away and in High PRF searching for a target.  Where it should then lock onto the target closest to the predicted intercept point should midcourse guidance not be reestablished/ either with TWS or a hard lock.

[currenthill]

I guess this is the same behavior I'm experiencing.

 

Was starting to question myself and my abilities, since the last update I can't seem to hit anything with 120C and SD10. The missiles' behavior are very strange.

 

 

120C goes where it wants.trk

[Oceandar]

I also noticed quite the same behaviour. Yesterday flew in GS and head on with MiG-29 I launched 120C inside 10nm and it was gone ballistic with no apparent reason. The MiG was tracked with radar and missile not launched in maddog.


Edit : I was in Hornet not in the Eagle.

[BIGNEWY]

AIM-120 Issues are already reported and being worked on by the team.

 

thanks

[nighthawk2174]

Issue seems to have persisted after the last patch.

 

 

 

AMRAAM_BUG_DropedTracks2.trk

[THE KING]

On 12/20/2020 at 5:23 AM, BIGNEWY said:

AIM-120 Issues are already reported and being worked on by the team.

 

thanks

Would you be able to verify whether or not this is a bug? 

Nothing against the guy on there who says it is not it’s just It would be nice to hear it from an ED official, thanks. 

Edited December 26, 2020 by THE KING

[BIGNEWY]

We have reported to the team, thanks for the tracks

[oldcrusty]

Are you guys seeing this in OB or stable?   I tried 6 scenarios in latest OB single player with different launch parameters and the missiles hit dead on. In all cases I put the radar to 'SIL' after missiles went active. The targets in each engagement were a pair of non-maneuvering cargo jets.

Yes, there's always a vid.  2 of these tests... if anyone wants to check:

https://youtu.be/Dq1Lf2Y2am4

 

[nighthawk2174]

37 minutes ago, Gripes323 said:

Are you guys seeing this in OB or stable?   I tried 6 scenarios in latest OB single player with different launch parameters and the missiles hit dead on. In all cases I put the radar to 'SIL' after missiles went active. The targets in each engagement were a pair of non-maneuvering cargo jets.

Yes, there's always a vid.  2 of these tests... if anyone wants to check:

https://youtu.be/Dq1Lf2Y2am4

 

Open Beta the track was taken after the hotfix yesterday, F15 lofted launches.    The bug appears that when track is lost the missile goes ballistic reverting to a 1g level flight.  This is incorrect as it should continue towards the last known intercept point going active and searching for the target on its own.  In your case, first clip, you supported the missile all the way till it nearly impacted and till they were already active for a few seconds in the second.  Hence you not seeing the bug. If you examine the trk file I posted earlier you will see I cut off midcourse guidance very shortly after launch. This bug though is particularly bad for lofting (not level shots as in the second engagement in your clip) as when they go to loft there is no chance of them ever seeing the target but if you launch straight like you did they may still have a chance of seeing the target.

 

Edited December 27, 2020 by nighthawk2174

[dundun92]

55 minutes ago, Gripes323 said:

after missiles went active.

Thats not the bug, the bug is when you drop the lock before active

[oldcrusty]

Yep, I see the problem with the missile seeker not predicting the intercept point.

I launched 2 missiles in the same setup, except this time I silenced the radar 28 seconds before the 2nd missile went active. This missile was still pointing slightly upward at the moment the guidance link was cut and it went stupid. The first missile was already beginning to point down at the link cutoff (about 22 sec. to active) and re-acquired when active.

Both missiles lofted from level flight. So yea... 

These targets were straight and level till merge. I guess I've never seen this issue before since normally the targets are maneuvering and I tried to guide for as long as possible.

https://youtu.be/pH8jxXKnZgs

 

Edited December 27, 2020 by Gripes323

[Old Sauveur]

Most of the exemples here don't take into account the change of 120 logic made by ED, that fixed almost completely the desyncs issues in A/A.

SD-10 & AIM120 has actually a seeker fov now (15 degrees to pick up on target). Those 120s are unsupported, so they have no chance to get out of the loft. Also due to their shooting range. The moment a track is no longer on memory mode, the Midcourse guidance and Autopilot is gone. Seeker can still acquire a target within it's seeker limit.

 

The challenge to adress to ED is, why is the 120 no longer travelling to the last known intercepting point of the target like before ? 

The autopilot and the guidance have lifetime at the moment.

 

There is a fine line between Magic INS and and actual auto-pilot INS.

I believe things will be fixed soon, Just a matter of time.

 

Happy end of year Festivities
 

Edited December 27, 2020 by Old Sauveur

[BIGNEWY]

Hi all,

 

The next, big task for modern air-to-air missile modelling will be the inclusion of coupled INS and data link. While we currently model these as separate systems, they are not currently tied. Once some other Hornet and Viper weapon tasks are complete, we will return to this. In the meantime, we'd advise properly supporting the missile until it goes active.

 

thanks

[NoJoe]

3 hours ago, BIGNEWY said:

Hi all,

 

The next, big task for modern air-to-air missile modelling will be the inclusion of coupled INS and data link. While we currently model these as separate systems, they are not currently tied. Once some other Hornet and Viper weapon tasks are complete, we will return to this. In the meantime, we'd advise properly supporting the missile until it goes active.

 

thanks

 

Sweet, thanks for the update, and for keeping your eyes on this thread, BigNewy.

 

Happy holidays!

[Svend_Dellepude]

On 12/27/2020 at 6:08 PM, BIGNEWY said:

Hi all,

 

The next, big task for modern air-to-air missile modelling will be the inclusion of coupled INS and data link. While we currently model these as separate systems, they are not currently tied. Once some other Hornet and Viper weapon tasks are complete, we will return to this. In the meantime, we'd advise properly supporting the missile until it goes active.

 

thanks

 

This can be a tough one in the Hornet right now with the occasional radar freezes when maneuvering.

[Harker]

EDIT: Only happens if RESET is used to clear the L&S. Unclear if RESET is supposed to sever the datalink of outgoing missiles, but apart from that, no bug. Please see my answer below Gripes' post.

From some tests I run in the F-18, the AMRAAM does not receive support unless the track file is currently designated as L&S or DT2. That happens even if the track is not lost, but simply undesignated post launch, like you would do if you wanted to fire on multiple targets by stepping the L&S through them.

Edited December 30, 2020 by Harker
Only occurs with RESET

[oldcrusty]

19 hours ago, Harker said:

From some tests I run in the F-18, the AMRAAM does not receive support unless the track file is currently designated as L&S or DT2. That happens even if the track is not lost, but simply undesignated post launch, like you would do if you wanted to fire on multiple targets by stepping the L&S through them.

 

I just tested this with 4 Amraams in 2 setups. First with loosely spaced targets using 'pinky' to sort and designate, then same 4 targets closely spaced using RAID. 

When using 'pinky' I had to closely watch where the L&S jumps. First it goes to DT2 of course. Then, for some reason went back to original L&S. The 3rd press moved it to the 3rd target then the 4th.

In RAID I used TDC (double click) to select the track I wanted. I was a bit clumsy but it worked.

To eliminate maneuvering variable I placed 4 heavy transports as targets.

Raw, unedited vid but shows the tracking and hits:

 

https://youtu.be/Pz7bytIygkA

 

[Harker]

1 hour ago, Gripes323 said:

I just tested this with 4 Amraams in 2 setups. First with loosely spaced targets using 'pinky' to sort and designate, then same 4 targets closely spaced using RAID. 

When using 'pinky' I had to closely watch where the L&S jumps. First it goes to DT2 of course. Then, for some reason went back to original L&S. The 3rd press moved it to the 3rd target then the 4th.

In RAID I used TDC (double click) to select the track I wanted. I was a bit clumsy but it worked.

To eliminate maneuvering variable I placed 4 heavy transports as targets.

Raw, unedited vid but shows the tracking and hits:

 

https://youtu.be/Pz7bytIygkA

You're right! I was testing by launching and pressing RESET to clear the L&S and DT2 and that apparently also severed the datalink to the missile. No idea if it's supposed to work like that. But at least the radar supports missiles correctly, if RESET is not pressed.

Thanks for taking the time to post this, I wouldn't have realized otherwise.

[Joni]

On 12/27/2020 at 2:08 PM, BIGNEWY said:

Hi all,

 

The next, big task for modern air-to-air missile modelling will be the inclusion of coupled INS and data link. While we currently model these as separate systems, they are not currently tied. Once some other Hornet and Viper weapon tasks are complete, we will return to this. In the meantime, we'd advise properly supporting the missile until it goes active.

 

thanks

 

 

Hello guys.

 

Quick question:

 

Was any of these items in last patch really applied to the game? Based on BN it seems to me they didn't, right?

 

Quote

AIM-120 AMRAAM active radar seeker bug fixing/improvements:

• Fixes in seeker target searching logics.
• Introduced last target LOS storing. When the target is lost, the seeker retains its orientation, directed to where the target was.
• Datalink. A fighter-missile line-of-sight check has been introduced.

 

[Blinky.ben]

6 hours ago, Joni said:

 

 

Hello guys.

 

Quick question:

 

Was any of these items in last patch really applied to the game? Based on BN it seems to me they didn't, right?

 

 

I could be totally wrong here but I read somewhere that the data link update is more of a preparing for a feature to come but not actually implemented yet.