Jump to content

[NO BUG] RWR / Jester picking up launches on other aircraft


Recommended Posts

Right now in the F-14 if a SAM locks on a friendly/other target (works even with a TALD, for example) then you will receive a lock tone (even if you're separated by 10nm or so) - this one is a long-standing ED bug as far as I know - HOWEVER, if the SAM launches at that other target, then your RWR will show that it has launched at you and Jester will start panicking and telling you to evade a missile that's not being fired at you. That last part is a new issue unique to the F-14. It makes life really difficult because in MP servers someone is almost always being fired at by SAMs, but you never know when it's actually firing at you.


Edited by IronMike
Link to post
Share on other sites

I too am getting this, but also from enemy aircraft that are getting BRA called by AWACS as being close to 200 miles away. They're firing at something on the other side of the map but my RWR is picking it up.

3800X, X570, 32GB 3600, RTX 2080Ti, SSD, Odyssey+ VR

Link to post
Share on other sites
seems to happen for other aircraft locking and firing too

 

Thanks - I thought that was the case but wasn't 100% sure when writing this up. It did actually get me killed earlier - had a human RIO in the back seat as we got pinged and we both thought it was another false RWR hit, until a missile hit us :(

Link to post
Share on other sites
If your plane is in the radar cone of the firing unit, you should be getting a launch warning. Your RWR cannot tell which plane is being locked, only that something is being locked and fired on.

 

It can happen from up to 100nm away from the looks of it, it's not that - there's no possible way I could be in any tracking radar cone. You don't have to be anywhere near the unit actually being locked for this to happen.


Edited by backspace340
Link to post
Share on other sites
Thanks - I thought that was the case but wasn't 100% sure when writing this up. It did actually get me killed earlier - had a human RIO in the back seat as we got pinged and we both thought it was another false RWR hit, until a missile hit us :(

 

Your Rio should look at rwr and then at direction for immediate confirmation of launch trail.

He has chaff control and also can advise whether it is going for you or someone else.

He will also handle the call out via radio.

Either ownship defending Sa something.

Or Sam launch rough position and whether it goes high or low.

Deadpool, pilot of "a very accurate simulation of the F-16C Block 50 operated by the United States Air Force and Air National Guard circa 2007" :megalol:

 

If you find yourself in a fair fight, your tactics suck.

― John Steinbeck

Link to post
Share on other sites
Your Rio should look at rwr and then at direction for immediate confirmation of launch trail.

He has chaff control and also can advise whether it is going for you or someone else.

He will also handle the call out via radio.

Either ownship defending Sa something.

Or Sam launch rough position and whether it goes high or low.

 

Thanks for the tips, but that doesn't solve the bug. That happened because we were miles away from the action and we assumed the bug was triggering again (like it had 50 times before that). It would just be nice to have launch warning = being launched on, like it is in every other module.

Link to post
Share on other sites
Thanks for the tips, but that doesn't solve the bug. That happened because we were miles away from the action and we assumed the bug was triggering again (like it had 50 times before that). It would just be nice to have launch warning = being launched on, like it is in every other module.

 

No worries. Didn't want to talk down on you. Sorry if it came over like that way.

 

Could this be related to the defect from Ed where a plane lock from ai will trigger everyone's rwr?

Deadpool, pilot of "a very accurate simulation of the F-16C Block 50 operated by the United States Air Force and Air National Guard circa 2007" :megalol:

 

If you find yourself in a fair fight, your tactics suck.

― John Steinbeck

Link to post
Share on other sites

Hi guys,

 

this is not a bug, but simply how realistic RWR works (not talking about the bug where 1 radar triggers lock for everyone, this seems to be a separate issue within DCS and not related to the Tomcat). It only knows there is a launch and it does not know whether this launch is on you or not. That it picks off launches from so far, is due to how these launches are being emitted in DCS: if they paint you, the RWR will respond to it, and with some radars that can be very far.

 

That other RWRs "know" which launch is on you and which not is rather not realistic. Also note that the F14s RWR coverage does not have dead zones, its inaccuracies come from other reasons.

 

This is not necessarily in direct reply to your question anymore, but please check out this overview written by our Grover, who designed the RWR:

 

The procedures/logic:

- Four sensors/antennas for the radar bands of tracking radars and airborne radars.

- Each antenna FOV is ~180° (or slightly more), and almost a perfect cone.

- The sensitivity at the edges of the cone is significantly lower than in the centre.

- When we get a message from DCS about being radiated, we simulate the signal it produces in each sensor. This includes factors such as the distance from the emitter (attenuation), the angle of arrival for each antenna, noise and other random signal amplitude fluctuations.

- From this moment we treat the signal as if we didn't know about the true parameters of the emitter and we only use the information from the emulated sensors (the previous step).

- We take the amplitude of the signal from each sensor, apply signal to noise cuts, combine and reconstruct the threat direction.

- Then, the reconstructed direction together with the signal signature is compared with the list of threats already being displayed. If we find one that correlates, we update its direction. Otherwise, we create a new threat and inform about it with the 'new guy' sound.

 

Some consequences of the procedure described above and a bunch of other features:

- No blind spots. However, if directly above or below, the threat has to be significantly closer (compared to the horizontal plane) to pass the SNR threshold.

- The direction is reconstructed in the 2D plane (the local aircraft frame of reference). For threats significantly outside that plane, their reconstructed direction may be inaccurate, and it usually shifts towards the 12, 3, 6, or 9 o'clock from the true position.

- The direction reconstruction accuracy improves as the distance from the emitter decreases. For the scan modes of the emitter (RWS/TWS), it's somewhere around 10-15° RMS.

- For the emitters in scan modes, a misassociation of a known-threat with a new signal can happen, and it occurs quite often, especially at long ranges. It can result in:

a) ghosts (fake threats) appearing on the display - more probable if you or the threat do some manoeuvres;

b) merging a group of two or more threats of the same type into one threat. For example, a group of two Su-27 flying in close formation, both scanning with their radars, can appear on the screen as one '29' until they get closer.

- A malfunction/damage of one antenna/sensor doesn't make you completely blind in that direction, as the two adjacent antennas should still cover that area. However, the lack of that sensor makes the direction reconstruction procedure very innacurate, and it's very likely that some threats will be displaced by more than 90°.

 

Compared with the default RWR from DCS:

- An entirely new dedicated code, written from the grounds up.

- Antenna/electronics emulation.

- Threat reconstruction using the emulated signals.

- Enhance information obtained from the engine with more details (radar modes, missile guidance, noise etc.).

- No blind spots.

- Imperfect like a real device should be, and not a god's eye.

a) Some weak radars can appear late.

b) The directions will be inaccurate.

c) It will be harder to estimate the number of threats of one type when they form a group.

d) You'll receive launch warnings not only when you are the target of the missile. For example when flying in a close formation with your buddy; if an enemy launches a weapon such as AIM-7 or SA-6 at your buddy, you may receive a launch warning from that threat as well.

- Detailed failures/damages.

 

Another thing to consider with the RWR is that the antennas move with the control surfaces, which means that this will roll your RWR picture, just as when you are maneuvering the aicraft, the RWR picture will roll with it (and might display erronous contacts). This requires additional pilot skill to take RWR readings at the proper (level) moment in the maneuver in order to keep up an accurate SA as well as an eye to spot wrong readings in between.

 

I hope this helps with understanding the RWR better.

 

Best regards, IronMike


Edited by IronMike

Heatblur Simulations

 

Please feel free to contact me anytime, either via PM here, on the forums, or via email through the contact form on our homepage.

 

http://www.heatblur.com/

 

https://www.facebook.com/heatblur/

Link to post
Share on other sites
Thanks for the tips, but that doesn't solve the bug. That happened because we were miles away from the action and we assumed the bug was triggering again (like it had 50 times before that). It would just be nice to have launch warning = being launched on, like it is in every other module.

 

IronMike made a good post above that goes into detail. Our simulation is simply deeper and more realistic.

 

The excessive range is a bug however and being looked at.

Nicholas Dackard

 

Founder & Lead Artist

Heatblur Simulations

 

https://www.facebook.com/heatblur/

Link to post
Share on other sites

This behaviour is realistic for radars in search mode only (nails/dirt).

 

In STT or launch guide mode, a radar cone is only in the vicinity of 2 degrees wide, +/- a bit depending on the system.

 

Therefore, everyone should get a nails/dirt/spotted when a search emitter goes active, but only the target or other aircraft in very close proximity to the target should receive STT or launch indications (spiked/mud/singer). This is the long standing DCS bug. At long ranges, the distance will be larger than at close range, but no way an aircraft 40, or even 10, miles away should get the threat indication unless they are directly in line front or back with the tracking beam, or many hundreds of miles away. I’m too lazy to do the trig to figure out what that distance is at 200 miles...


Edited by Sandman1330

Ryzen 9 3900X / Asus Crosshair VI Hero X370 / Corsair H110i / EVGA GTX 1080ti FTW3 / 32Gb G.Skill TridentZ 3200 / Samsung 960 Evo M.2 / Virpil Warbrd base + VFX and TM grips / Saitek X56 Throttle / Saitek Pro Combat pedals / Rift S

Link to post
Share on other sites
IronMike made a good post above that goes into detail. Our simulation is simply deeper and more realistic.

 

The excessive range is a bug however and being looked at.

 

Thanks cobra, I hope you guys manage to fix it soon as the warnings from across the map can be pretty distracting and confusing. Also, nice simulation and nice writeup ironmike!

Link to post
Share on other sites

Sidelobes

I agree that DCS exagerates that part a bit but assuming you need to be in the mainlobe to get a RWR detection isnt accurate either.

[sIGPIC][/sIGPIC]

 

*unexpected flight behaviour* Oh shiii*** ! What ? Why ? What is happening ?

Link to post
Share on other sites

Awesome writeup, IronMike. That answers all my questions/concerns. I am very pleased the F14 models the RWR more realistically, though I will have to change how I fly, being used to (unrealistically) using the F5 RWR as a passive localization and intercept tool.

 

I hope the AI radar behavior and consequential launch warnings from 200 nmi away ends up getting resolved. As it is, I am usually ignoring the RWR if I haven't heard Jester calling out bandits within 20 nmi.

Link to post
Share on other sites

If I could clarify it a bit further, and split the problem into two: the range and the geometrical relations (cone in which the radar beam is emitted).

 

Let's start from the range. There are four antennas on the aircraft receving radar waves. Their sensitivity - and thus the received signal strength - depends on the angle of arrival of the radar wave. The RWR electronics anaylzes the strengths from the antennas, and reconstructs the relative direction of the emitter. As you can see, there's no direct information on the signal emitter distance from the aircraft. It's hidden in the signal strength, but the relation isn't simple. I'll give you two examples when the signal received can be low but the threat real. The emitter can use a low emission mode (even the F-14 has low range, low emission ACM radar modes) and you as the threat won't know about it. The threat may be directly below or above you - because of the antenna type used in the RWR, the signal received from below or above can be very low. All of above makes the RWR unable to calculate the distance from the threat accurately enough to apply hard cuts on the threat distance. It's better to get a few false positive alerts than to get one false negative, and be shot by a missile about which you wasn't warned from the RWR.

 

The geometrical relations.

The main beam lobe width of a tracking radar can be as large as 10-15 degrees. Plus there are side lobes. The same applies to the missile guidance signal. In DCS, the emitter owner (module) decides which objects are withing the beam geometrical limits, and sends information about being painted by the radar to those objects. Maybe some systems are a bit too generous in informing about being locked, but it's not something we can control.

 

The real life RWR have limitations, and are less precise than we - the flight simmers - usually imagine them. Our goal was to recreate that realistic, imperfect behaviour, and we want to make it even better. And our next step will be the ALR-45/ALR-50 for the F-14A, which is even more analog and much simpler system.

Krzysztof Sobczak

 

Heatblur Simulations

https://www.facebook.com/heatblur/

Link to post
Share on other sites

With all that said...will the RWR code be available to other aircraft in the sim? We can't go on having all this inconsistency from module to module. Things need to be looked at as a whole.(where its applicable of course)

[sIGPIC][/sIGPIC]

 

AMD FX 8350 4.0 Ghz CPU , ATI RX 560 4 gig GPU ,32 gig ram on Win7 64bit.

Link to post
Share on other sites
  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...