reported Hostile targets return IFF and show friendly symbology

[Arctic Fox]

When interrogating hostile contacts with IFF, hostile targets appear to incorrectly return what appear to be partial M4 return symbology (yellow square, though incorrectly scaled). After acquisition into STT and NCTR interrogation, the hostile target I was using (a MiG-23) to test appeared as a green friendly track. Needless to say, both of these things seem very wrong.

The mission I tested with had no other aircraft to contribute datalink information for target classification. I have not tested what the behaviour is with datalink in play.

The mission I was using to test and a track are attached.

Viper IFF Test.miz F-16 IFF Test.trk

Edited October 28, 2022 by Arctic Fox

[WHOGX5]

The yellow square means that the MIG-23's IFF is responding but with an incorrect code/key which is normal if you're on different teams. The strength of NATO's Mode 4 IFF is that together with the interrogation pulse a code is sent and if that code doesn't match the code of the day, the interrogated aircraft doesn't respond and therefore doesn't reveal its location. The interrogated pilot will also receive an audio cue to alert him that he's been unsuccessfully interrogated with Mode 4 (which is quite concerning if you're a NATO aircraft).

However, a incorrect response from an interrogated aircraft should definitely not ID the contact as a friendly.

[Arctic Fox]

The MiG-23 should in no way return a Mode 4 response to my interrogation. Let's imagine it has NATO IFF equipment built in (DCS currently abstracts this), it would not reply in Mode 4 to an incorrect interrogation relative to its own codes. It would stay quiet to not give away its position.

EDIT: (as you've basically said yourself)

Edited October 28, 2022 by Arctic Fox

[llOPPOTATOll]

The MIG-23 does not have a Mode 4 IFF transponder, so it should not replay at all. Mode 4 unknown symbology should be pretty rare to see. It means that there are valid mode 4 replies being received, but not enough to overcome the threshold for it to show a green circle.

Edited October 28, 2022 by llOPPOTATOll

[falconzx]

I don't think commanding IFF scan would result an answer with angle+range from enemy units, it's correct to receive that info from succesfully iff (friendly aircraft).

With this patch is even useless to use the radar. To find enemies location in this patch, regardless their range, is enough an iff scan. I think this is a serious issue that worth a fast hotfix. @BIGNEWY

[NineLine]

3 hours ago, Arctic Fox said:

When interrogating hostile contacts with IFF, hostile targets appear to incorrectly return what appear to be partial M4 return symbology (yellow square, though incorrectly scaled). After acquisition into STT and NCTR interrogation, the hostile target I was using (a MiG-23) to test appeared as a green friendly track. Needless to say, both of these things seem very wrong.

The mission I tested with had no other aircraft to contribute datalink information for target classification. I have not tested what the behaviour is with datalink in play.

The mission I was using to test and a track are attached.

Viper IFF Test.miz 9.38 kB · 2 downloads F-16 IFF Test.trk 653.86 kB · 3 downloads

 

I'm sorry to ask as we are super busy right now, but can you make a track using the Caucasus Map? I wont have much time to check it over or convert to that map, and many of the devs responsible for systems like this do not have other maps installed for reason such as debugging, etc. 

If not, I will have to wait till later or tomorrow to check it out and make a new track. Thanks!

[falconzx]

The new yellow M4 bad answer of IFF, is coming from all bandits, even if you haven't found them on your radar.

In simple words, a cheat! 

 

f-16_IFF_scan_see_all_bandits.trk

[Arctic Fox]

4 hours ago, NineLine said:

I'm sorry to ask as we are super busy right now, but can you make a track using the Caucasus Map? I wont have much time to check it over or convert to that map, and many of the devs responsible for systems like this do not have other maps installed for reason such as debugging, etc. 

If not, I will have to wait till later or tomorrow to check it out and make a new track. Thanks!

Here you go.

Upon further investigation it looks like the classification of the contact on NCTR is based on its coalition. While flying a blue F-16 and interrogating a red target, the contact showed up red. While flying a red F-16 and interrogating a blue target, the contact showed up green.

While flying a red F-16 and interrogating a red target the contact showed up yellow, which I can only presume is the result of a conflicting "two factor" classification based on friendly IFF and "hostile" (red) NCTR print. AIFF response being correlated to track classification is in itself incorrect behaviour according to the MLU manuals.

F-16 IFF Test - Red F-16 vs. Blue.trk F-16 IFF Test - Red F-16 vs. Red.trk F-16 IFF Test - Blue F-16 vs. Red.trk

Edited October 29, 2022 by Arctic Fox

[Spectre1-1]

for the viper its partial answer, which is still wrong, but... yay ?!

[Geraki]

AIFF Yellow square must occurred with mode SCAN number in it, for unknown mode reply like Green circle for known IFF response reply near fcr target.

Edited October 29, 2022 by Geraki

[Geraki]

AIFF Yellow square must occurred for unknown mode reply like Green circle for known IFF response reply near fcr target.

[MARLAN_]

It may be helpful here to add that a neutral coalition also returns a "hostile" NCTR print in the F-18, I wouldn't be surprised if it's a shared system with the F-16.

[Frederf]

Mode 4 is a secure form of IFF unlike Modes 1/2/3. Mode 4 is designed not to transmit when being interrogated with the wrong code because that would be a glaring security flaw. The enemy would just spam out interrogations and listen for any response. Mode 4 unknown indication should be very rarely (in DCS never?) displayed.

[uther419]

Not sure if this has been seen or is working as designed,

Doing f16 vs f18 BVR, the interrogator allows a "god" view against the bandit. TMS left press causes yellow unknow to appear at ranges up to 100nm.

The interrogator works during emcon quiet and jammer operation. 

When coupled with TMS up hold and press allows the f16 in a 1v1 BVR fight to have a massive advantage to search and find a target.

I feel like the interrogator should make a null return / the range should be much shorter. At the very least, the interrogator should not work during emcon modes.

Thank you!

See attached screenshots for example

Screen_221108_221545.jpg.url

Further, it the interogattor seems to ignore terrains.

Opponet was using terrain masking and i was able to find him while also flying NOE

[skywalker22]

Track please. Save it and paste it here. Make a short demonstration.

And I hope you put an F/A-18 on the red side, if you were blue, right? Else you can get connected with Link16.

[okopanja]

@uther419track file is usually captured inside Saved Games\DCS openbeta\Tracks\Multiplayer for multiplayer games. For SP mission, use debrief option to explicitly save the file.

I recommending adding also tacview file/screenshot.

Btw: I heard the rumors of this, so I believe you do not imagine, and likely ED already knows about this.

Edited November 9, 2022 by okopanja

[bukizzzz]

Saw it already on another thread, and can confirm the bug myself

I think it's been reported already

[falconzx]

2 hours ago, bukizzzz said:

I think it's been reported already

Confirmed. I reported this too in Bugs section.

[uther419]

Sounds good, I will add the track tonight

[uther419]

F18;was blue f,16 was red

[Arctic Fox]

An update on this: As of the current patch, the problem of NCTR print creating a wrong track classification when flying on REDFOR still seems to exist.

Continuing issues with AIFF symbology and how its functionality is currently implemented in the F-16 I have outlined in the other thread on this subject here (which really should be in the bug reports rather than wish list forum).