Help understanding IFF please

[Woody01]

Hi guys, I know IFF is not properly implemented atm, but as far as I understand its simplified and if you have a radar lock and it is a box its friendly if it is a diamond it is hostile.

We just flew a night intercept mission where we had to locate a stolen Georgian airliner full of escaped dirty insurgents escorted by two Mig21's heading to Dirkadirkastan. There were 4 FA18's in our flight and once we merged with the Mig21's it was all on for young and old. Trouble is I had a solid lock close with a diamond, I held it for maybe 20 seconds trying to get my SA (totally black, like flying in ink) but it was showing hostile lock the whole time, "Fox 2!" still diamond until moments before splash then it turns to a square! and yes it was my wingman! Splash...

Not good for squadron cohesiveness...

Can anyone explain beyond 'Its borked' how I could have known it was my wingman? I know communication etc... But atm I am at a loss and loosing confidence in the FA18 in a fur ball because the information displayed to me is incorrect. I know this has been an issue in previous patches but I was surprised to see it is still doing it.

Anything you think I am missing? I shot a guy down in a public server a few months ago in the same fashion and I was mortified! Getting a bit sick of it...

[Retu81]

Strictly speaking the diamond doesn't mean "Hostile", it means that the system hasn't got "Friendly" response. The target might be hostile, neutral or a friendly with issues with its IFF system or just bad signal. That's why making a decision on target's posture based on IFF alone might be a bad idea and why Rules of Engagement exist IRL.

 

Don't feel bad, though. You're not the first virtual pilot and not the last who's done that. :)

[Woody01]

Thanks for your response mate, makes sense of course.

Its just when your in a knife fight in a phone booth you have to make decisions quickly, I guess I just made the wrong one.

Thanks for your reply, I have learnt from it.

[corvinus]

Did you take a look at https://forums.eagle.ru/showthread.php?t=224752 ?

 

Currently you have to make sure target is within the pitch ladder. If it is outside the pitch ladder you do not get a response (i.e. you see a diamond).

[backspace340]

Strictly speaking the diamond doesn't mean "Hostile", it means that the system hasn't got "Friendly" response. The target might be hostile, neutral or a friendly with issues with its IFF system or just bad signal. That's why making a decision on target's posture based on IFF alone might be a bad idea and why Rules of Engagement exist IRL.

 

Don't feel bad, though. You're not the first virtual pilot and not the last who's done that. :)

 

That's not true - diamond means hostile. Square means unknown/no IFF response. ED have not modelled friendly yet (which is a square with FRIEND written on top). We just have a simple check of whether something is hostile and it'll show the diamond if it is (if it's within the pitch ladder) - it's not an accurate modelling of how IFF works.

[Retu81]

That's not true - diamond means hostile. Square means unknown/no IFF response. ED have not modelled friendly yet (which is a square with FRIEND written on top). We just have a simple check of whether something is hostile and it'll show the diamond if it is (if it's within the pitch ladder) - it's not an accurate modelling of how IFF works.

 

Ah, thanks for clarifying that. So the system makes the distinction between neutral/enemy by other means than pure IFF response? By NCTR and/or something else.

Edited November 18, 2018 by Retu81

[backspace340]

Ah, thanks for clarifying that. So the system makes the distinction between neutral/enemy by other means than pure IFF response? By NCTR and/or something else.

 

Right now it's just using the game logic - it's really not simulating any real aspect of it other than checking what coalition (i.e. Blue or red) it belongs to as far as I know. In real life apparently the only thing that can designate a target as hostile is either the pilot themselves or other people doing so via datalink. NCTR apparently can't change the designation. So we've got a bit of a fudge right now but it was always meant to be a short term fix - it'll probably get fleshed out later.

[Banzaiib]

That's not true - diamond means hostile. Square means unknown/no IFF response. ED have not modelled friendly yet (which is a square with FRIEND written on top). We just have a simple check of whether something is hostile and it'll show the diamond if it is (if it's within the pitch ladder) - it's not an accurate modelling of how IFF works.

 

That, backspace340, is exactly the opposite of how it works. No plane identifies itself as hostile, that would be stupid. Please, Mr. F-18, shoot me down!

 

IFF only receives positive friendly identification. Diamond means no response or hostile, but you cannot positively tell the difference without visual identification. Square means definitely friendly... now, whether that works in DCS, is a whole other story.

Edited November 19, 2018 by Banzaiib

[DAZnBLAST]

I don’t really care about the underlying science behind it all. If a SU27 or Mig29 can tell in an instant whether I’m a friend or foe in my F18 or F15 etc. I would like my F18 to be able to do the same thing. In other words, keep it consistent between the modules. ;)

[Mike Wazowsky]

That, backspace340, is exactly the opposite of how it works. No plane identifies itself as hostile, that would be stupid. Please, Mr. F-18, shoot me down!

 

IFF only receives positive friendly identification. Diamond means no response or hostile, but you cannot positively tell the difference without visual identification. Square means definitely friendly... now, whether that works in DCS, is a whole other story.

That is all correct, except that you may not need a visual ID (VID). Depending on the ROE in use, a combination of factors allows to declare (friendly, bogey, bandit, hostile, etc...) the targets. For example, IFF readings, hot heading, high speed, low level outside corridor, being off a pre-planned transition level, using fire control radar... there would a theatre-wide matrix that determines which combination of factors lead to a certain "dec". Moreover, NCTR (also called a "print") allows to determine with certainty which type of aircraft we are facing. In a theatre where those types only belong to the OPFOR, that could be enough to declare. Also, if C2 (AWACS, GCI...) declares a target, it's on them... the crew is perhaps responsible for reporting facts that may disagree with that declaration, and may have the authority to change it. All of this, of course, works for the western world...

[backspace340]

That, backspace340, is exactly the opposite of how it works. No plane identifies itself as hostile, that would be stupid. Please, Mr. F-18, shoot me down!

 

IFF only receives positive friendly identification. Diamond means no response or hostile, but you cannot positively tell the difference without visual identification. Square means definitely friendly... now, whether that works in DCS, is a whole other story.

 

Sorry, but you're wrong and it's easy to see how it's wrong with real footage. Skip to about 2:30 in this video and you'll see an Iraqi Mig-21 marked with a square on a Hornet's HUD. Square cannot mean definitely friendly.

 

 

If DCS were properly modelling IFF then we wouldn't see the diamond at all (until we have datalink or the ability to change designations ourselves) - we'd just see square for unknown and square with FRIEND on top for friendlies (which would work exactly as you've described diamond/square working). Track files can apparently be designated hostile by the pilot themselves manually or by the AWACS operator and sent over datalink (which is probably what caused that track file to turn to a diamond in the video - the AWACS had already declared that contact a bandit a while before the shootdown as the pilot explained on the fighter pilot podcast).

 

I understand that everyone understands how IFF works, but ED have modelled it in a way that is counter to everyone's understanding - we do not have a 'friendly' marker in the game, so there is no positive-only IFF working at all. All the game does is tell us when something is hostile.

Edited November 19, 2018 by backspace340

[Tenkom]

I understand that everyone understands how IFF works, but ED have modelled it in a way that is counter to everyone's understanding - we do not have a 'friendly' marker in the game, so there is no positive-only IFF working at all. All the game does is tell us when something is hostile.

Then why does targets start out as hostile and then, after some sort of identification turn friendly?

It seems to me that the plane considers everything hostile until proven otherwise.

If the game only has a "hostile" signal then the default target symbol should be square.

[backspace340]

Then why does targets start out as hostile and then, after some sort of identification turn friendly?

It seems to me that the plane considers everything hostile until proven otherwise.

If the game only has a "hostile" signal then the default target symbol should be square.

 

It doesn't - the target starts out as square the first time you lock anything, if it's a hostile it'll then switch to a diamond. If you THEN lock a friendly, it starts as a diamond before quickly switching to square. But, if you lock an enemy but drop the lock before it switches to a diamond, and then lock the friendly, you never see the diamond. Basically, it's an EA quirk you're seeing, not an IFF system at work - it's remembering what the last contact was (square/diamond) and displaying that first. You can see that here:

 

 

For anyone still not convinced, this is the explanation from the Hornet's manual:

 

 

You can check it yourself in Program Files\Eagle Dynamics\DCS World OpenBeta\Mods\aircraft\FA-18C\Doc, this is on page 123-4.

[hardnick]

I don’t really care about the underlying science behind it all. If a SU27 or Mig29 can tell in an instant whether I’m a friend or foe in my F18 or F15 etc. I would like my F18 to be able to do the same thing. In other words, keep it consistent between the modules. ;)

 

I think so too.

[wrl11]

I agree on this, even if its a "FC3" non realistic fix. IFF should be a top priority on the F/A-18 even if an unrealistic solution is required for a while.