investigating JTAC jammed my radio communications

[BoundaryLayer]

I was playing the A-10C single-player mission Defend Camp Yankee, which I editted the player's a/c to be A-10C II.

On station of IP, I checked in with JTAC (VHF 30.00MHz FM, assigned by the mission editor) by radio ARC-186, and since then I received no response from JTAC at all. Furthermore, all my radio communications menus stopped working.

In details: all three radios were functional, i.e. I could turn it on, off, tune frequencey, etc.; I could also receive the radio from another A-10C flight (that he was passing waypoint, spotted AAA, etc.) and ground units if tuned to the correct frequency. The problem is that I could not send any radio by the \ menu (I played realistic radio, so dedicated usage on ARC-210, 164 and 186). Nromally, for example, if I call my wingman to rejoin, I would hear my own transimision "2, join up." first, then the response "2, rejoin.". However, in this bugged mission I could not hear any of my transimission on all 3 radios, and thus no response from anyone, either wingman, jtac, ATC, etc., as if my radio call is jammed by the initial check-in with the JTAC. In the game I then strafed the bugged JTAC with HEI but he took zero damage. I don't know if it could be that the JTAC might be killed by enemy mortar when receiving my very long check-in radio call, and thus a bug is triggered, just a guess. 

This bug didn't always happen. I played this mission 4 times today, and there were twice that the JTAC didn't respond to me: once I could still use my radio to contact others; and the other time is the bugged one, and the track is attached. And usally, the JTAC would respond to me "no more tasking, good job" if there is no task, but sometimes he doesn't.

jtac.trk

[razo+r]

\ is usually used for the intercom if I remember correctly. 

Have you also tried using the dedicated Mic switches?

[BoundaryLayer]

14 minutes ago, razo+r said:

\ is usually used for the intercom if I remember correctly. 

Have you also tried using the dedicated Mic switches?

Yes, I used realistic comm, but I changed the default keyboard bindings for each radio of the three. I only use the default \ on ground to call groudn crews.

The "\ menu" might be a bit misleading (as I couldn't come up with a better concise name for it), but I just meant the dedicated radio here, such as ARC-186 for VHF 30MHz to JTAC, ARC-164 for UHF 251MHz to wingman, etc.

[Yurgon]

7 hours ago, BoundaryLayer said:

Furthermore, all my radio communications menus stopped working.

This is an odd problem indeed.

In your track, I saw exactly what you described. After your check-in with the JTAC, the player stopped transmitting radio messages. I took control of the track and still was unable to transmit messages on either radio.

I then ran the track again, took control immediately, and the radios worked just fine.

At some point in the track I believe you switched the Frequency Selection Dial on the ARC-186 FM radio to the EMER FM position. On that position, you'd be transmitting and receiving on a dedicated guard frequency and no longer be able to talk to the JTAC. However, that should not stop transmissions from working at all, and should have 0 effect on the other radios.

Given the hard to reproduce nature of this issue, if you can somehow isolate the one cause for this issue, that would go a long way to eventually getting it fixed by ED.

Edited November 20, 2023 by Yurgon

[BoundaryLayer]

7 hours ago, Yurgon said:

switched the Frequency Selection Dial on the ARC-186 FM radio to the EMER FM position

Seems I misunderstood this dial selection (thought it's just a FM/AM selection), but indeed I could not use any other radio either then.

 

7 hours ago, Yurgon said:

the hard to reproduce nature of this issue

That's true, I played twice more this mission after reporting this post, and evrything went well. The first JTAC even warned me "Abort! Abort! Abort!" before he was killed by enemy mortar, since one plausible cause to the bug, which I thought, could be his sudden death during transmitting. And later comm with the second JTAC went also well.

I recall that the bug in the attached track occurred when I Ctrl+Z the game during check-in with the JTAC. In the later two games, I did all transimission in normal game speed all the way. Don't know if this matters.

[BoundaryLayer]

On 11/21/2023 at 1:26 AM, Yurgon said:

if you can somehow isolate the one cause for this issue

So, since the last post, I've played this mission about 5 more times, and today this bug occurred again. The track file is attached. I didn't finish the mission to the end since I couldn't issue orders to my wingman (I really cannot spot infantry so the wingman is greatly needed, lol).

The story in this track is: I was orbitting around IP and asked one of the JTAC's for tasking; 9-line, remarks, readback, standby data, IP inbound, contact to marks were all good; as I was approaching the target, I chose Maverick as my weapon instaed of CBU-97 as ordered by JTAC; to find a better attack route (avoiding the trees that blocked my LOS to the target) I flew close to JTAC while kept tracking the target by TGP; I don't know if it was this reason, at this moment JTAC called "Abort! Abort! Abort!" (in what circumstances would JTAC call this usually?); I ignored this and continued trying to attack; after shooting my Maverick, I called out the VHF menu (251MHz, dedicated to contact with my wingman) to ask him to attack the second target on my SPI; now the same bug occurred that the comm stopped working, I couldn't contact anyone again.

I wondered if it was due to JTAC, so I hovered back to the second target and destroyed it with CBU-97. Now JTAC congrated me and told me no more tasking and may depart. I thought this could have broken the jammed comm by JTAC, but it did not. I still couldn't use the comm menu. Game quited.

Edit: In addition, I did not install any Mods, eveything is original DCS, except the mission .miz, which I editted it in ME to my preference. If needed, I can upload the .miz.

jtac_jammer_2.trk

Edited November 22, 2023 by BoundaryLayer

[Yurgon]

1 hour ago, BoundaryLayer said:

at this moment JTAC called "Abort! Abort! Abort!" (in what circumstances would JTAC call this usually?)

I'll take a look at the track later (unless someone beats me to it).

Regarding this question: Once an attack has been approved ("Cleared Hot"), the call "Abort, abort, abort!" is used when the attack must not be continued and has to be, well, aborted.

I think the DCS JTAC might call "Abort, abort, abort" even before giving the "Cleared Hot" call, which wouldn't be great from a procedures point of view. But the DCS JTAC is very limited anyway.

A typical reason for an abort-call by the DCS JTAC would be the wrong final attack heading; when you're given an attack cone like "Make your attack heading 150 to 210" your jet has to point somewhere between 150 and 210 degrees during the run-in, otherwise you're outside of the briefed parameters and the JTAC can call off the attack.

(The phraseology "150 to 210" is really bad because of the phonetically ambiguous "to" which sounds just like "two"; there are much better options like "Make your final attack heading 180 +- 30 degrees" or "Make your final attack heading between 150 and 210", and nowadays I believe the standard phraseology is actually "Make your final attack heading between 150 clockwise 210" - but the DCS JTAC isn't up to date. )

Edited November 22, 2023 by Yurgon

[jaylw314]

Not related to the bug, but with a human JTAC, the abort call could also be if the JTAC loses visual on the attacking aircraft (required for Type 1, desired for Type 2).

I think in DCS, if you are not heading towards the designated target area, the AI JTAC will also call an abort

Edited November 22, 2023 by jaylw314

[Yurgon]

13 minutes ago, jaylw314 said:

Not related to the bug, but with a human JTAC, the abort call could also be if the JTAC loses visual on the attacking aircraft (required for Type 1, desired for Type 2).

Good point!

And of course the situation on the ground could change. Maybe friendlies are closer to the target than expected, or civilians show up, or the target moves away from the DMPI, or something as silly as the JTAC messing up the laser code or the laser designator in case of ground-based laser-illumination.

Some of these would also probably prompt the DCS JTAC to call an abort, like when the target becomes obstructed during run-in for a ground-based laser-illumination.

[jaylw314]

It would be interesting to test if LOS for the AI JTAC actually matters, but again, not related to the bug at hand

[BoundaryLayer]

18 hours ago, Yurgon said:

I'll take a look at the track later (unless someone beats me to it).

Regarding this question: Once an attack has been approved ("Cleared Hot"), the call "Abort, abort, abort!" is used when the attack must not be continued and has to be, well, aborted.

I think the DCS JTAC might call "Abort, abort, abort" even before giving the "Cleared Hot" call, which wouldn't be great from a procedures point of view. But the DCS JTAC is very limited anyway.

A typical reason for an abort-call by the DCS JTAC would be the wrong final attack heading; when you're given an attack cone like "Make your attack heading 150 to 210" your jet has to point somewhere between 150 and 210 degrees during the run-in, otherwise you're outside of the briefed parameters and the JTAC can call off the attack.

(The phraseology "150 to 210" is really bad because of the phonetically ambiguous "to" which sounds just like "two"; there are much better options like "Make your final attack heading 180 +- 30 degrees" or "Make your final attack heading between 150 and 210", and nowadays I believe the standard phraseology is actually "Make your final attack heading between 150 clockwise 210" - but the DCS JTAC isn't up to date. )

 

That's really quite a lot details implemented and to be implemented, great effort! Even though I often ignore JTAC's requested attacking angle, he doesn't always call abort, either. But anyway, contacting with JTAC in full procedure is a super cool role-play to me!

Hope the cause of this bug could be located eventually 

[Yurgon]

On 11/22/2023 at 5:09 AM, BoundaryLayer said:

So, since the last post, I've played this mission about 5 more times, and today this bug occurred again. The track file is attached.

Excellent, thanks!

In the track I saw exactly what you described. I took control after the radio problem appeared and was no longer able to send commands to my wingman (nor anyone else). The wingman also didn't react to commands like "Break left!", so it's not just a case of missing audio and/or subtitles. Radio commands just don't get sent any more.

This is quite curious.

I guess I'll have to dig a little deeper to find the common denominator for those cases where the problem occurs. If you happen to see this issue in any other mission, be sure to let us know!

BTW, I believe the "Abort" call from the JTAC was indeed given because you were outside of the assigned attack cone while getting close to the target.

[Yurgon]

I built myself a new mission with the player flight (2 A-10C II), an AWACS, 2 JTACs, 10 hostile BTRs as primary targets, and on top of that a hostile mortar team that harasses one of the JTACs. In several attempts, I couldn't get my radios to fail. In one flight, the JTAC unit I was working with got destroyed, but my radios were okay and I was able to continue with the other JTAC.

I'm wondering if maybe there's something in that old mission you've been using that causes the issue?

[BoundaryLayer]

29 minutes ago, Yurgon said:

I built myself a new mission

I did similar to build a simple JTAC training mission and it goes all well.

30 minutes ago, Yurgon said:

I'm wondering if maybe there's something in that old mission you've been using that causes the issue?

Could be. I don't know how old the mission was built for A-10C, so there might be some later updates to the game and ME that cause some issues.

One thing I noticed is that there were two IP's created in the old mission: one is TOWEL placed around the IP waypoint of A-10C, and it is indeed used by JTAC during communication; the second one is placed somewhere north with no callsign given, and it seems not be used. I tried to select either of them to edit, but failed. Selecting TOWEL opens the menu of trigger zone North Outpost Marker Zone (I don't remeber the exact name, it is used for the somke marking the north outpost), and selecting the other IP opens the menu of South Outpost Marker Zone. I just couldn't edit these two IP's at all. I then deleted these two trigger zones, and now nothing happens if I click either of 2 IP's, they are non-selectable.

I also checked the mission file in the .miz, and located the scripts of these two IP's. They seemed unspecial. I deleted them and went back to ME, and now they are gone. So I created a new IP and it's editable.

I've just become interested in ME recently, and thus use the A-10C missions as practice to edit them to my preference. I only have limited programming skills that aid me reading the mission scripts but couldn't provide me with an entire clear picture of how the script flow works. So I might have missed something that could trigger undesired features, but the IP issue described above should be a legacy problem of the game update itself, and there might be more potential ones I think.

[Yurgon]

2 hours ago, BoundaryLayer said:

[...] but the IP issue described above should be a legacy problem of the game update itself, and there might be more potential ones I think.

Yeah, when I open a copy of the mission in the ME, I get the same. Instead of selecting an IP, I get a dialog for a trigger zone, although I hid all of them.

Normally the ME should update the structure of a mission once it's saved, but saving my copy of this mission didn't help. Also quitting the ME and opening the previously saved mission afterwards didn't help.

While I have no idea how something in an old mission might cause radios to break in flight (but only sometimes, and seemingly under random circumstances), it seems that's exactly what happens here.

Welcome to the wonderful world of DCS mission editing. 

Edit: If you have the time (and provided you've got the old A-10C module installed), can you fly the original mission in the old A-10C and check if the problem appears there as well?

Edit #2: I've filed a bug report with the Closed Beta Testers and have referenced this thread there.

Edited November 24, 2023 by Yurgon

[jaylw314]

Is there a reason to believe the problem is the radios failing vs the AI wingmen and JTAC becoming unresponsive?  The latter have both been intermittent bugs I've experienced over the years in past updates, so it's not out of the realm of possibility 

Edited November 24, 2023 by jaylw314

[Yurgon]

9 hours ago, jaylw314 said:

Is there a reason to believe the problem is the radios failing vs the AI wingmen and JTAC becoming unresponsive?

Two of them.

a) Transmitting radio commands no longer plays the associated audio files ("Two, break left!", "IN", or whatever).

b) Other stations still transmit messages that can be heard by the player, meaning their AI isn't completely switched off (see the above remark about "No further tasking. You may depart" after the last target was destroyed).

Did you play the tracks? It's evident in both of them that after a certain point, transmitting radio messages via the F-keys no longer works.

[jaylw314]

1 hour ago, Yurgon said:

Two of them.

a) Transmitting radio commands no longer plays the associated audio files ("Two, break left!", "IN", or whatever).

b) Other stations still transmit messages that can be heard by the player, meaning their AI isn't completely switched off (see the above remark about "No further tasking. You may depart" after the last target was destroyed).

Did you play the tracks? It's evident in both of them that after a certain point, transmitting radio messages via the F-keys no longer works.

Ah, no, I did play the track, but I missed the fact that the player audio was not playing 

It just reminded me a lot of trying to play TEW 3.0 a couple years ago and suddenly not having the AI JTAC and wingmen respond, but IIRC the player audio was still playing...

[Yurgon]

1 hour ago, jaylw314 said:

It just reminded me a lot of trying to play TEW 3.0 a couple years ago and suddenly not having the AI JTAC and wingmen respond, but IIRC the player audio was still playing...

Yeah, the AI JTAC going mute was a DCS issue for way too long, and it was right around the time TEW received an upgrade and people played it a lot. Ran into that issue myself then. And it was always tremendous fun having my player read the 5 minute long check-in (well, almost ) hoping that this time the JTAC would finally wake up and talk to me.

Edited November 24, 2023 by Yurgon

[BoundaryLayer]

18 hours ago, Yurgon said:

an you fly the original mission in the old A-10C

Not likely, since I changed quite a lot of default key bindings to A-10C II, so I need to do the same to each control of the old A-10C as well if I will play it.

Now I'm moving on to a new mission Hideout! Edit and play it 

BTW, the IP selecting issue mentioned above, also occurred in the mission CASR. Looks like it's the same age as the Yankee base one.

[BoundaryLayer]

On 11/24/2023 at 1:10 PM, Yurgon said:

I've filed a bug report with the Closed Beta Testers and have referenced this thread there.

I've encountered a similar radio issue recently on F-16, which is quite similar to the one of A-10C II, so I think I will just post it here (or should I start a new thread in F-16 forum?). The track file is attached.

It is "The Night Life" mission of F-16C, which I editted a bit while keeping the story original. In the track, after dropping bombs to the target and finally egressing (at the late stage of the game in the track), somewhere I noticed my UHF radio is jammed, and the DED keeps looking like the following (UHF channel being used)

The radio issue again is that both "Transimit Switch - UHF/VHF (call radio menu)" stopped working, i.e. after clicking the desired radio message, I couldn't hear my own transmit, and thus no respond from the receiver.

However, the interesting part is that after pressing the key of "Transimit Switch - UHF (VOIP)", the jammed UHF is fixed; and, all the previously stucked transimits (as if they were buffered in sequence in the game while the UHF was jammed) that I randomly conducted (to AWACS, flight, ATC...) now are being sent one by one. After that, the radio menu worked again.

I hope this may give a hint to fix this radio bug. Perhaps the JTAC is innocent, while the implementation of the radio menu is bugged.

night.trk

[Yurgon]

On 12/7/2023 at 8:29 AM, BoundaryLayer said:

The radio issue again is that both "Transimit Switch - UHF/VHF (call radio menu)" stopped working, i.e. after clicking the desired radio message, I couldn't hear my own transmit, and thus no respond from the receiver.

Sorry for the late response.

I didn't watch the track because you said the issue only appeared at the end of a long mission.

Do you remember if the "UHF" indication on the DED remained in inverted video like in your screenshot during the entire time that the problem persisted? So far I haven't received any feedback on the bug report, but if the "UHF" remains inverted, that would point to the outgoing transmission somehow being stuck, and thus blocking any further comms from going out. That would certainly be a very interesting aspect to add to the internal report.

[BoundaryLayer]

On 12/19/2023 at 11:51 AM, Yurgon said:

Do you remember if the "UHF" indication on the DED remained in inverted video like in your screenshot during the entire time that the problem persisted?

Yes it was, as if the UHF channel was still being used.

On A-10C there is no indication whether the radio is being occupied, but for F-16C I noticed this inverted video of UHF. This gave me the hint to hit the Transimit Switch - UHF (VOIP) to see if the problem could be fixed, and it indeed worked. So maybe the jammed radio on A-10C II could also be fixed in a similar way once it happens. 

I guess this is not an issue to a specific aircraft, but rather the radio mechanism implemented in DCS.

[Yurgon]

9 hours ago, BoundaryLayer said:

I guess this is not an issue to a specific aircraft, but rather the radio mechanism implemented in DCS.

Excellent, thanks for the update! I've amended the report.

[BoundaryLayer]

9 hours ago, Yurgon said:

Excellent, thanks for the update! I've amended the report.

So I took control of the very first track of A-10C II in this post. After the radio was jammed, I hit the VOIP radio key. The stucked radio messages to JTAC then magically (as expected) started transmitting , radio fixed! Confirmed that both radio bugs reported here should be due to the same cause regardless of aircraft.

Hope this be helpful in degbugging.