correct as-is Does the Datalink Actually Work?

[SharpeXB]

Does the datalink actually “work” and receive signals from donor aircraft? Either in MP or SP. Or is it just a mini F10 map sorta thing? I don’t notice it corresponding with bandit calls from my wingman or AWACS, if it “worked” wouldn’t any target they see with their radar appear on it? 

Edited May 20, 2022 by SharpeXB

[Ramsay]

13 hours ago, SharpeXB said:

Does the datalink actually “work” and receive signals from donor aircraft? Either in MP or SP. Or is it just a mini F10 map sorta thing?

Yes DCS's Link-16 datalink is modelled "as a thing" but it's greatly simplified compared to the real i.e.

• there is only a single "NET",
• it doesn't frequency hop (so is "jammed" by certain TCN channels in DCS)
• messages can't be relayed beyond the range of a single aircraft/radio i.e. in many cases Link-16 is limited to LoS of the AWACS and it's radio range (~120? NM)
• AWACS acts as a "HUB" to translate between different formats (i.e. A-10C SADL) and share data (PPL?) across different groups.
• IIRC, although AI aircraft data is passed though the NET, player data is limited to fellow squadron/aircraft (may have been a FA-18C or EA limitation - I'm mostly on PvE servers)
• the data link isn't an "Eye of Sauron" that sees everything, there are times AWACS will call out contacts that it isn't sharing or miss contacts whilst in a turn, etc.
• an element of data lag/signal delay is modelled
 

Edited May 20, 2022 by Ramsay

[SharpeXB]

On a particular mission I was surprised to watch the Tacview and see many enemy aircraft but the datalink showed none. I know of course that radar isn’t an all seeing eye but it’s seems odd that all the bandits can avoid it continually. 

Edited May 20, 2022 by SharpeXB

[Ramsay]

1 minute ago, SharpeXB said:

I know of course that radar isn’t an all seeing eye but it’s seems odd that all the bandits can avoid it continually.

Are you sure the datalink was working and there wasn't a conflicting TCN station/tanker ?

If you could "see" friendlies and it was was only enemy contacts that were missed - detection can very much vary depending on mission geometry i.e. altitude of the AWACS, target sizes, etc. - in particular DCS's AWACS radar limits/detection ranges seem weaker than publicly available data.

I haven't looked at the datalink in detail recently but last time I looked at a "problem" mission (IIRC 2020) - everything worked out correctly with detection issues explainable by

• mission geometry (hot/cold/flanking)
• poor E3 radar angular limits
• hard coded RCS and detection ranges

The best thing would be to break the "suspect mission" into smaller pieces and test individual groups to see if detection works/is explainable or if your problems are limited to MP/late activated units.

Note: I have a SP mission (SP and Coop) that uses MOOSE to spawn in enemy AI aircraft and play on the 4YA Syria server without issue but these mostly depend on a single AWACS, rather than other AI or player aircraft.

[SharpeXB]

It was working to the extent that I could see friendlies and some enemies. But the majority of the bandits weren’t displayed. My question seems answered though in that the datalink apparently does function in DCS akin to the real world which is good to know. For a moment I though it might just be a faux repeat of the F10 map or something.  

[Paul_Exotic]

I think there may be a DL bug in the new OB patch. Some friends and I were playing around last night, and our hornets were unable to see each other on the SA page.  Link 16 was definitely on in both hornets and the Viper but no joy seeing each other on the SA page.

[NineLine]

You may be confused about wingman DL. You will only get a flight member DL track when the flight members sets a target as an L&S, It will not send search contacts.

Only a C2 asset like AWACS will send surv (search) contacts.

As always a track helps though.

[Aphelion079]

2 hours ago, Paul_Exotic said:

I think there may be a DL bug in the new OB patch. Some friends and I were playing around last night, and our hornets were unable to see each other on the SA page.  Link 16 was definitely on in both hornets and the Viper but no joy seeing each other on the SA page.

Change your NET code to the same code, (even though it's already on the same one) and you'll turn blue for each other.

[Hulkbust44]

You may be confused about wingman DL. You will only get a flight member DL track when the flight members sets a target as an L&S, It will not send search contacts.
Only a C2 asset like AWACS will send surv (search) contacts.
As always a track helps though.

I believe you are confusing this with the SA friendly designation/STT/under attack lines.

A fighter would always be contributing to tracks on the network. If DCS dosen't work that way, that explains a lot of the problems.

It would be pointless to only show the threats donors see when they have them designated. That's what the attack status lines on the SA are for.

[dorianR666]

4 hours ago, NineLine said:

It will not send search contacts.

that cant be right

even f-14's primitive link-4c shares search contacts between flight members

Edited May 20, 2022 by dorianR666

[Harker]

You may be confused about wingman DL. You will only get a flight member DL track when the flight members sets a target as an L&S, It will not send search contacts.
Only a C2 asset like AWACS will send surv (search) contacts.
As always a track helps though.

It absolutely should, all aircraft detected are shared. That's the entire F/F part of the DL. I think you're talking about the TXDSG function, which will show designations and dashed lines to L&S targets.

[BIGNEWY]

7 hours ago, Harker said:

It absolutely should, all aircraft detected are shared. That's the entire F/F part of the DL. I think you're talking about the TXDSG function, which will show designations and dashed lines to L&S targets.

It is correct based on the very limited data available, if you have better information that can be used by the public please PM me. 

thank you

[MARLAN_]

With respect, I am confused -- we know the F-18 is capable of sharing its sensor information to the network to support track files (as confirmed by Nineline, ED already believes that an L&S designated target should be shared, so the capability is already there) so why would the F-18 not also share non-L&S sensor information? It's purely common sense logic. As mentioned by others, L&S is only applicable for TXDSG for designation line and launch line (we are missing launch line) and all sensor information contributing to track files is shared to the network.

I 100% totally understand not simulating the exact parameters of classified material because you'd then need to prove how you knew (for example) an AMRAAM can fly 123.456NM and wasn't just a lucky guess, but this is common sense logic. Is not allowed for the public to apply deduction & logic? Seems really silly to me. I understand ED needs to be very careful, but sometimes this just doesn't make sense to me and it sounds like from what I hear in various DCS community portals that it feels like excuses to avoid dedicating further development.

Edited May 21, 2022 by MARLAN_

[NineLine]

The Hornet documentation we have indicated only L&S.  If they have contrary, documented evidence, they can PM it.

If those other community portals feel we are avoiding work, that is their choice, we can only say what we know, and that is we base things off the best documentation we have. Please stick to the report, and leave the suggestive insults that we are avoiding completing something for who knows what reason... its simply weird to suggest we would not develop something to its fullest if we have the proper information. It can stop right now, and stay on those other DCS community portals. 

[NineLine]

Let me state that one more time.

You guys that suggest this is wrong, send me, BN, or Wags even the evidence and we will revisit, you guys come at us so strong like all this info is sitting right there available to all, then send it our way and we will take a look, otherwise stop the comments like we are silly, or wrong, or whatever else. 

We have never said we have all the answers, if you have more, share it, share the documents, and not from your uncles brothers cousins housemaid who was once a Hornet pilot, real evidence that is legally obtainable. 

[Hulkbust44]

Let me state that one more time.
You guys that suggest this is wrong, send me, BN, or Wags even the evidence and we will revisit, you guys come at us so strong like all this info is sitting right there available to all, then send it our way and we will take a look, otherwise stop the comments like we are silly, or wrong, or whatever else. 
We have never said we have all the answers, if you have more, share it, share the documents, and not from your uncles brothers cousins housemaid who was once a Hornet pilot, real evidence that is legally obtainable. 

Our question is what made you (not you, the dev team) model it the was it is? Show us *why* this is correct. Especially when it comes to the whole STT range fiasco. You vehemently defend the way it's modeled while it goes against all common sense and logic regarding the subject. You can't tell us where you sourced the information? All we got was "the team is happy the way it is."

All we want is more communication.

[NineLine]

We based it off the manuals, documents and SMEs we have, we are not going to share what we have (see 1.16). We have been doing this for many years, and while we are not perfect, and do admit we make mistakes, it is up to YOU guys to prove its wrong, not us to prove it is right. You may see that as unfair, but I do not understand that thought process, if you have real evidence it is wrong, show us, if you do not, then why are we still wrong? (you can claim common sense, yet if you have more common sense then us, then explain why with evidence, otherwise common sense is nothing more than opinion)

As I have said, I have asked for some white papers on missile design and other systems that are very very undocumented so you guys get a better idea of how we fill in the gaps and our design decisions, but at the end of the day, this is our job, this is our pride and passion, we want it to be as real as possible, but as stated over and over, if you have more tangible evidence, besides a YouTube video from some foreign air force with no documents, or just word of mouth or opinion, then sorry, we are going to go with our team, our SMEs and our documents.

PS, the topic is Data Link.

[MARLAN_]

1 hour ago, NineLine said:

The Hornet documentation we have indicated only L&S.  If they have contrary, documented evidence, they can PM it.

If those other community portals feel we are avoiding work, that is their choice, we can only say what we know, and that is we base things off the best documentation we have. Please stick to the report, and leave the suggestive insults that we are avoiding completing something for who knows what reason... its simply weird to suggest we would not develop something to its fullest if we have the proper information. It can stop right now, and stay on those other DCS community portals. 

Thanks for the response. It's always a good reminder for everyone to hear that the most realistic sim is desired and the team is passionate. We all love this sim and want it to be the best it is. I only mentioned it because I notice a lot of support is wavering in the past months/year (times have been really tough globally though), I didn't mean to offend.

I am sending some proof your way about MIDS/Data Link shortly.

[Theranthil]

On 5/20/2022 at 4:11 PM, Ramsay said:

Yes DCS's Link-16 datalink is modelled "as a thing" but it's greatly simplified compared to the real i.e.

• there is only a single "NET",
• it doesn't frequency hop (so is "jammed" by certain TCN channels in DCS)
• messages can't be relayed beyond the range of a single aircraft/radio i.e. in many cases Link-16 is limited to LoS of the AWACS and it's radio range (~120? NM)
• AWACS acts as a "HUB" to translate between different formats (i.e. A-10C SADL) and share data (PPL?) across different groups.
• IIRC, although AI aircraft data is passed though the NET, player data is limited to fellow squadron/aircraft (may have been a FA-18C or EA limitation - I'm mostly on PvE servers)
• the data link isn't an "Eye of Sauron" that sees everything, there are times AWACS will call out contacts that it isn't sharing or miss contacts whilst in a turn, etc.
• an element of data lag/signal delay is modelled
 

 

 

Are you refering to the picture below ? I sometimes had very bad D/L receptions in the missions but I wasn't able to link it with the TACAN.

Are the colored channel jamming the L16 and should we avoid them in the missions ?

 

Edited May 25, 2022 by Theranthil

[Ramsay]

6 hours ago, Theranthil said:

Are you refering to the picture below ?

Some players use the diagram but ...

6 hours ago, Theranthil said:

I sometimes had very bad D/L receptions in the missions but I wasn't able to link it with the TACAN.

... like you, I find the channels don't match up with the TCN channels that "jam" the data link in DCS.

6 hours ago, Theranthil said:

Are the colored channel jamming the L16 and should we avoid them in the missions ?

Personally, I have a "white list" of safe TCN channels (created from experience with previous missions) I use.

• Low channel numbers (1-4) seem safe
• Channel numbers similar to CVN's (68-76) seem safe
• IIRC TCN channels around 8-13 cause link-16 issues but as this is from memory, you'd need to test if you want certainty.

History

When DCS's link-16 was first released, by chance it conflicted with low TCN channels and CVN numbers, this caused issues for a number of user missions, so DCS's data link frequency was "tuned" by ED to avoid these. IRL link-16 data channel hops across a frequency "band" and never spends more than a few micro-seconds on any particular "frequency".

[Nuclearwinter76]

This public video on MIDS/JTIDS/Link 16 is particularly informative about the sensor information sharing capacity of the network:

Particularly the section beginning at 10:30 describes the capacity for aircraft in the network to transmit their combat state and sensor data to the AWACS which is then forwarded to other aircraft in the network. 

Sources for the video are given at the end, including BAE systems (manufacturer of MIDS terminals)

[Laurreth]

On 5/25/2022 at 3:41 PM, Ramsay said:

IRL link-16 data channel hops across a frequency "band" and never spends more than a few micro-seconds on any particular "frequency".

According to a 2020 "INTRODUCTION TO TACTICAL DIGITAL INFORMATION LINK J AND QUICK REFERENCE GUIDE" ("Approved for public release; distribution is unlimited."), "the transmission frequency of the terminal is changed for each pulse (77,000 hops per second) through 51 discrete UHF frequencies." I am so far not sure how those frequencies are distributed across the 960-1215MHz band, but the hopping pattern is derived from cryptographic keys and I highly doubt that it can be limited to only a chosen subset.

It is very likely safe to assume that either the network in a given theatre is set up to reliably accomodate all participants, or that any participant conforming to specifications will be equipped to communicate across the entire potentially used band; otherwise, it would be near-impossible to have reliable encrypted communication. The one stated limitation is restriction to line of sight (due to the chosen UHF band), so it would be fair to limit range significantly if, e.g., an AWACS isn't available. That said, some fighters like the F/A-18C would be able to act as relays (source is the same document). (edit) This is of course a bit vague since "line of sight" only precludes over the horizon transmissions, not BVR communication.

From the perspective of simulating such a system in an environment like DCS, I'd go for the "magic" approach and assume that it "just works" in its entirety. Otherwise, limitations like enabling TACAN on specific frequencies breaking what's otherwise a blackbox system must be documented.

Edited June 22, 2022 by Laurreth

[Blackfyre]

I'd suggest change the tag from "correct-as-is" to "half-implemented-internally"