I'm Getting lock warning when SAM locking at someone

[FalconPlot16]

Is this a bug ? When enemy sam was targetting someone i'm being spiked too but im sure he is not locking at me because im very far away from that sam's range.

[Habu_69]

I believe the F/A-18C aircraft has no way to determine which aircraft the SAM launcher is tracking, so the warning you hear is that the SAM is emitting a lock radar freq and you better watch out. Refer to the EW display to determine the relative bearing of the radar signal. Then in daylight fair weather you can usually see a launched missile exhaust trail and determine whether or not it is tracking you.

[104th_Maverick]

You're supposed too. As Habu says the aircraft doesn't know if its your jet that is being locked or not, all it knows it that it is detecting radar energy that indicates some system has an STT lock on an aircraft.

 

 

If you fly through this radar energy you will get a lock warning, even if you are not the aircraft being targetted.

[FalconPlot16]

ok then its not a bug

[xjiks]

You should read this topic:

https://forums.eagle.ru/showthread.php?t=221983

[Harker]

Aren't radars supposed to be using range gates in STT though, as to maximize the beam focus on the target? I get it if you're between the radar and its target, but it's strange getting lock warnings if you're 20NM behind the target.

Or is it that the radar paints that specific line in 3D space and uses a range filter to simply select the desired target, out of all the targets that it's painting?

[KlarSnow]

Radars have beamwidth, they are not laser pointers. if you have a 1 degree beamwidth (a really good tight beamwidth for an A/A radar) the beam is physically 1 degree wide expanding out into space. Remember thats vertically as well as horizontally.

 

At 30 miles that beam is a half mile wide, at 60 miles its 1 mile wide, and yes it is absolutely radiating in front of and beyond the target. You could be more than twice as far away as the locked target and still be receiving the same or more energy than the reciever on the threat radar that is locking your buddy.

[Harker]

Radars have beamwidth, they are not laser pointers. if you have a 1 degree beamwidth (a really good tight beamwidth for an A/A radar) the beam is physically 1 degree wide expanding out into space. Remember thats vertically as well as horizontally.

 

At 30 miles that beam is a half mile wide, at 60 miles its 1 mile wide, and yes it is absolutely radiating in front of and beyond the target. You could be more than twice as far away as the locked target and still be receiving the same or more energy than the reciever on the threat radar that is locking your buddy.

OK, fair enough, I get that the wave widens as it goes, because of the distance and other factors, but at the same time, isn't the beam intensity decreasing as per the inverse square law? At a certain distance, the received energy should be low enough to not trigger the RWR, especially since it has libraries to correlate radar signature with expected signal strength. Of course it'll be programmed to err on the side of caution, so it'll produce an alert probably well beyond the radar's calculated range.

 

So the question is, how far behind from the intended target do you have to be in order to not receive a spike warning? I don't know, but there has to be a limit. Is that limit simulated in DCS? To some extent. I don't know how well. I just did a test and I got a spike from an SA-10, 180 NM away. Whether this distance is realistic or not, I've no idea. Maybe it makes sense that if I could pick up the Big Bird search radar at 180 NM, I could also pick up the necessary energy for a spike from the Flap Lid track radar.

 

I'm not saying it's necessarily incorrect, I'm just posing a question regarding detection and RWR logic. I don't know about the exact numbers etc.

[KlarSnow]

How far has the wave travelled to get back to the radar that sent it and register as a lock and detection... twice as far as the range to the target. (if the target is at 30 miles, the wave has to have traveled 30 to the target, bounced off and a further 30 back to the locking radar) So if you have an equally sensitive sensor on the other side of the target, at least as far as twice the range you can successfully detect something... This would be a good minimum guideline

[KlarSnow]

Big bird btw is the EW radar, not the engagement radar for the SA-10, so by DCS logic since it can see you at 180 miles or more, your RWR will light up. The engagement radar is the FL (flap lid) That's the one you have to watch out for regarding Mud or Singer indications (ground radars don't follow the same terminology of nails and Spike that air intercept radars do)

[nighthawk2174]

When a radar tracks something it isn't a like a laser beam often there is a cone often in the range of .5 - 2°'s in size. And if your in that cone you'll get the launch warning/lock tone same as everyone else. That being said I think that in DCS you get the warnings way to far outside of the cones but i'd need to test first. Additionally from my understanding of RWR's what trigers a lock warning/launch tone is not necessarily a change in power but a stark change in the PRF of a radar.

[Harker]

Big bird btw is the EW radar, not the engagement radar for the SA-10, so by DCS logic since it can see you at 180 miles or more, your RWR will light up. The engagement radar is the FL (flap lid) That's the one you have to watch out for regarding Mud or Singer indications (ground radars don't follow the same terminology of nails and Spike that air intercept radars do)

Maybe I was unclear, I got a lock tone from the FL, labeled 10 in the RWR. At the same time, I got the BB on my RWR as well. Both at 180 NM. Nothing before the 180 NM. Of course I can't get a lock tone from the BB, since it's the search radar.

 

I theorized that since I can pick up the BB, it might be logical that I can also pick up the FL that was tracking a target along my azimuth (actually I was on the extended line from the SA-10 to the target, I made sure I was in the beam). I just find it a little odd that I'd pick up both at 180 NM, but I'm guessing that's either an RWR limit in sim or an SA-10 limit in the sim.

[Harker]

When a radar tracks something it isn't a like a laser beam often there is a cone often in the range of .5 - 2°'s in size. And if your in that cone you'll get the launch warning/lock tone same as everyone else. That being said I think that in DCS you get the warnings way to far outside of the cones but i'd need to test first. Additionally from my understanding of RWR's what trigers a lock warning/launch tone is not necessarily a change in power but a stark change in the PRF of a radar.

Agreed for the first point, but a modern RWR should use wave characteristics (searching vs tracking vs supporting a launch) as well as signal strength and compare it to its internal database. Both of these should be used when an RWR decides whether that Su-30 radar is a threat or not (non-lethal band vs lethal band, not currently modeled). At least that my understanding, based on the literature I've come across.

 

Right now in DCS, the F-18's RWR does not take signal strength into account. On the F-18's RWR, everything that's not engaging you is placed in the non-lethal band and only radars that lock you are moved to the lethal band; you can have a Flanker right in front of you and it'll placed in the non-lethal band as long as it's not locking you up. The DCS F-16 on the other hand, takes only signal strength into account and only uses the diamond on the highest threat and the flash with the circle upon a launch. The latter might be correct, but I doubt that the former is. I can point you to a thread regarding the ALR-67(V)2 RWR that the Hornet should have, where some people who know more than me are posting: https://forums.eagle.ru/showthread.php?t=235510

 

 

EDIT: I dug up a document that clearly says that both signal strength and RF characteristics are taken into account and that signal strength is indicated to the pilot, on the first iteration of the ALR-67, but I can't post it here.

Edited January 21, 2020 by Harker

[Ahmed]

The RWR should indeed discern between lethal and non lethal threats but this got lost in translation during development of the Hornet.

 

Regarding the lock warnings, the RWR should not only issue lock warnings when an aircraft nearby* is locked but also launch warnings. The RWR in dcs used to do this but it was changed several months ago and now it doesn't have them even when flying fingertip with the target.

 

Hopefully all this will be fixed one day but as the publicly available documentation is rather limited it is unlikely.

Edited January 21, 2020 by Ahmed

[Northstar98]

Hmm, I'm not sure, I'm aware that RADARs cover a small arc (laser pointers do the same too) and theoretically the emissions can travel much farther than the instrumented RADAR range (theoretically infinite if I'm not mistaken, obviously intensity falls off with the inverse square law, attenuation etc).

 

However, I've just flown an anti-ship mission in the Hornet using the Harpoon on the current stable build, nothing else around apart from the ships.

 

The only AD systems this groups of ships had were the SA-N-4 'Gecko' (naval SA-8) SAM and AK630 CIWS. The former has a max-range of ~8nmi.

 

From the perspective of the ship group, my Harpoons were on a bearing of around 100°, 7nmi away at around 2500ft and diving. My Harpoons were on a heading of ~280° towards the ships.

 

I on the other hand was on a bearing of ~120° from the ships, ~40nmi away, at ~20,000ft. I started getting STT warnings on my RWR from the ships engaging the Harpoons (I was way out of the range of the SA-N-4, so pretty confident they're not engaging me).

 

It just seems odd that the 'Pop-Group' FCR the SA-N-4 uses would have that large of a beam-width for tracking and engagement - it's land based equivalent "Land Roll" has a ~1° mainlobe for tracking & engagement.

 

Unless of course, I'm picking up a sidelobe, though I doubt it because I didn't think DCS went that far in simulating RWRs or RADARs.

 

 

Action begins at ~12:38:00.

FA-18C_RWR_01.trk

Edited April 17, 2020 by Northstar98