AIM-54 Changes / new API fixes are live in today's patch

[Harlikwin]

 

Because in TWS the radar only sweeps over the target once in a while, while in STT it's staring at it constantly? Honestly, that's pretty basic radar stuff...

 

You know that, and I know that... I bet he didn't though, based on what I read in his responses.

[Harlikwin]

 

I hope we're not confusing the AIM-54 missile messages with the LINK-4 datalink which is VHF.

 

Yeah, that also seems to be the case. Though if you want to pick nits its right at the bottom of what is classically considered UHF (300mhz).

[FWind]

 

Yeah, that also seems to be the case. Though if you want to pick nits its right at the bottom of what is classically considered UHF (300mhz).

 

https://apps.dtic.mil/sti/citations/ADB010399

The report was write in 1977. some technology in the report may be used to the AIM-54A/C.

[Harlikwin]

 

https://apps.dtic.mil/sti/citations/ADB010399

The report was write in 1977. some technology in the report may be used to the AIM-54A/C.

 

Thanks, interesting, Probably the C IMO,. though amusingly the digitization of it leaves something to be desired.

[GGTharos]

Not sure what you’re saying/asking there...

 

That it's a little strange to operate CW and PD from the same dish simultaneously - there's no reason to use the CW TWT to send the messages given that the PD one can easily do so. But, we often find things are designed in a way that we didn't expect so the question he is curious about and so am I, is why was this design choice made?

 

 

[UWBuRn]

Back IT, i ran again some test with the latest OB (18th November), against a large target (Tu-22) non maneuvering, no ECM and no chaffs (turned off from mission editor) flying at 0.9M, 35k feet.

• Shot an AIM-45C at 75 nm in TWS, keep lock till missile hit, TTI at 32 jumped to 16 (flashing), missile hit after 3-4 seconds of TTI reaching 0
  
• Shot an AIM-45C at 75 nm in TWS, kept lock till missile was 15 nm from target (broke with PLM), missile lost track, when TWS reacquired the track the missile started going after the target again even if the track on the TDI was not indicating the target beign shot at
  
• Shot an AIM-54C at 75 nm in TWS, kept lock till missile was 15 nm from target (broke with PLM and the shutted off radar), missile missed target going far above target
  
• Shot an AIM-45C at 75 nm in PDSTT, kept lock till missile was 15 nm from target (broke with PLM), missile lost track, when TWS reacquired the track the missile started going after the target again even if the track on the TDI was not indicating the target beign shot at
  
• Shot an AIM-54C at 75 nm in PDSTT, kept lock till missile was 15 nm from target (broke with PLM and the shutted off radar), missile hit the target
  
• Shot an AIM-54C at 75 nm in PDSTT, kept lock till missile was 15 nm from target (broke by commanding Jester and the shutted off radar), missile hit the target
  
• Shot an AIM-54C at 75 nm in PDSTT, kept lock till missile was 15 nm from target (broke by turning away), missile missed target going far above target
  
• Shot an AIM-54C at 75 nm in PDSTT, kept lock till missile was 15 nm from target (broke with PLM, holding PLM), missile missed target going far above target
  

So TWS/PDSTT still seems off to me:

• PDSTT once lost shoud be lost and should not switch to A
  
• A TWS guided missile should not receive target updates from what in fact it's another track
  

The TTI jumping, while odd, it's a welcome change (or workaround, i bet it does when the missile actually goes pitbull) as it makes things more predictable.

[Harlikwin]

Similar note, it seems like RWR warnings are much closer than 10mi still perhaps having to do with the TTI being off?

 

[GGTharos]

Back IT, i ran again some test with the latest OB (18th November), against a large target (Tu-22) non maneuvering, no ECM and no chaffs (turned off from mission editor) flying at 0.9M, 35k feet.

 

This is very good test run.

 

• Shot an AIM-45C at 75 nm in TWS, keep lock till missile hit, TTI at 32 jumped to 16 (flashing), missile hit after 3-4 seconds of TTI reaching 0

 
Weird, sounds like a bit of cheating/workaround is going on but it's kind of ok - if you're paying attention it's almost like the missile has a 2-way datalink, since this is telling that the missile has reached active distance as opposed to just trusting the timer and the WCS to send the active command :)
 

• PDSTT once lost shoud be lost and should not switch to A
  
• A TWS guided missile should not receive target updates from what in fact it's another track
  

The TTI jumping, while odd, it's a welcome change (or workaround, i bet it does when the missile actually goes pitbull) as it makes things more predictable.

 

Right on the first obviously, and on the second, DCS does not simulate command channels ... that channel would have been dead, not to be used again so the DL would have never resumed - and importantly the active command would not have been sent AFAIK.

[TeamMaximus]

 

That it's a little strange to operate CW and PD from the same dish simultaneously - there's no reason to use the CW TWT to send the messages given that the PD one can easily do so. But, we often find things are designed in a way that we didn't expect so the question he is curious about and so am I, is why was this design choice made?

 

 

Actually, it's not strange. On the F-4E, the AN/APQ-120 radar tracked (pulse) and illuminated (CW) the target through the same feedhorn on the antenna. The RF from the CW klystron transmitter was sent through a high-power RF circulator that isolated the receiver and the pulse transmitter magnetron from the CW rf. Of course, the F-4 was shooting AIM-7's, not AIM-54's, but the SARH mode is identical (AIM-7's don't have the DL capability, and neither did the APQ-120).

 

 

[GGTharos]

 

Actually, it's not strange. On the F-4E, the AN/APQ-120 radar tracked (pulse) and illuminated (CW) the target through the same feedhorn on the antenna. The RF from the CW klystron transmitter was sent through a high-power RF circulator that isolated the receiver and the pulse transmitter magnetron from the CW rf. Of course, the F-4 was shooting AIM-7's, not AIM-54's, but the SARH mode is identical (AIM-7's don't have the DL capability, and neither did the APQ-120).

 

 

Ok, that makes sense.

[Spiceman]

 

Yeah, that also seems to be the case. Though if you want to pick nits its right at the bottom of what is classically considered UHF (300mhz).

 

You are absolutely correct. IRL I was an engineer on the FAA’s CPDLC system for years which is VHF datalink and it was stuck in my head. Good catch.

 

[captain_dalan]

Guys? I just did the Persian Gulf "Beyond Visual range" and "On alert 5" missions and i actually did see the TTI numbers flashing at around 16s. Does this mean the Phoenix now works as intended? Has anyone tried this yet as well? And yes, judging by the missile trajectory, the time the TTI went flashing coincided with them going from loft to intercept.

[eatthis]

 

Last time... should likeley be irrelevant due to the broken/old API before today's patch.

 

They would have hit in SARH, if they would have had enough energy. Since the timer was rather random-ish at times with the old API, hard to say in such a situation. Note also that the timer goes on when the missile misses the target until it self destructs, I forgot how many seconds after the calculated impact.

 

The TTI is btw also WCS calculated tti, not real tti.

 

EDIT: If a track is lost the missile will not go active at all. If a contact is lost or not correlating with track anymore, however, and the track only gets updated by dead reckoning and not by real radar returns, after a certain time, the missile will receive an active signal and get sent to the last assumed position of the lost track. Such stored track files can last up to two minutes, for example when launched with "track hold". A lost track cannot be reacquired as in receiving all of the same data displayed for the same missile. In both cases there is no symbology iirc to notify you on the hud/ etc. In that sense, assume the missile was trashed to be on the safe side.

 

How does the missile active command work from the rio pit? Is the signal in the radar emmission or something else?

Ie could you turn cold and then send the command are do you need to send the command 1st?

with stt the phoenix is semi active all tye way, can the go active command still work with that?

what happens if you have multiple phoenix in the air and you press tye button? Do they all go active or just the last 1 fired?

[SgtPappy]

Guys? I just did the Persian Gulf "Beyond Visual range" and "On alert 5" missions and i actually did see the TTI numbers flashing at around 16s. Does this mean the Phoenix now works as intended? Has anyone tried this yet as well? And yes, judging by the missile trajectory, the time the TTI went flashing coincided with them going from loft to intercept.

 

So I tested this online with a friend - I was flying with Jester against my buddy in the F/A-18C and he got warning but at 8 s TTI, not 16 s even though the 16 s TTI indicator started flashing. I fired from TWS from 30 nm. We repeated this several times while I was flying above or below my target and the same results happened. I have not yet tried the experiment while being a RIO or having a human RIO. I also have yet to see if the AIM-54 goes dumb if fired from TWS at a range > 16 TTI. It does against AI, that's for sure. However the F-14 AI do not give warning at all if they fire from beyond PAL range.

 

Chaff seems to work very well against the AIM-54 unlike before the patch (don't know if the CM resistance has been dropped back to what it was or if it was updated so some other value since the patch notes say both those things happened somehow). However, we could not get it to reacquire once it went for chaff. It seems like a mixed bag but it certainly is not as horrible as it was several patches ago when beaming at all would cause a lost lock.

[Triggerjo23]

 

You know that, and I know that... I bet he didn't though, based on what I read in his responses.

 

You need to read through the comments a bit beter I think. We are not discussing this from a position of complete ignorance. We know the radar modes and it seems like you are confusing fox 1's with fox 3's. A lot of the information posted seems to be from Wikipedia after googling SARH.

[Triggerjo23]

 

It's transmitted by the same dish, the same TWT, on the same frequency.

 

Of course, pretty sure it would throw us all for a loop if you were able to name the radio on which the DL is transmitted, if it isn't the radar dish.

 

Again were is the documentation to support that data link to the missile is the same frequency. I did not say then data link was on a radio, I said it is a diferent frequency as far as I know. Again, were is the documentation.

[Triggerjo23]

Was reading the manual, and found this quote:

 

So in PD-STT at least HB states the target should get a launch warning.

 

Where does HB state that the target should get a launch warning from PD-STT (SARH/DL). That would settle the argument don't you think and since I have not seen this when reading the HB manual so can you link it please? Thanks.

[Triggerjo23]

The AWG-9 transmitter has two TWTs, one for the radar and one for CW. CW is used for SARH illumination and also for AIM-54 Missile Messages which are a modulated version of CW and sent out the CW antenna which is a waveguide opening at the bottom center of the AWG-9 antenna.

 

I hope we're not confusing the AIM-54 missile messages with the LINK-4 datalink which is VHF.

 

I am not confusing the DL with link-4 as far as I know it should be on a diferent frequency as others have told me. I have said I am looking for the right answer here as some tell me one thing and others tell me another but there never seems to be documentation to back it all up. Well if I can not see the documentation how do I know the others do and they are not just speculating. Documentation was posted which states that the Phoenix uses SA-PD antennas which would make sense for PD-STT then goes active with A-PD and not SA-CW. I think it is posted on page four to six on this thread. Also, other missiles of the same era used methods of tracking which meant that even when in STT a fired Fox 1 would not give a missile warning and this was by using data link. Considering that the Phoenix which is of the same era, is a fox 3 and made by a country with more technology, and the missile uses DL then why would it not be possible for it to track without a missile warning using SARH/DL. FWind posted information to the contrary of your claim that the Phoenix use SA-CW, as far as I know SA-CW is for the AIM-7. You see the confusion here I hope.

[QuiGon]

• Shot an AIM-45C at 75 nm in TWS, kept lock till missile was 15 nm from target (broke with PLM), missile lost track, when TWS reacquired the track the missile started going after the target again even if the track on the TDI was not indicating the target beign shot at
  
• Shot an AIM-54C at 75 nm in TWS, kept lock till missile was 15 nm from target (broke with PLM and the shutted off radar), missile missed target going far above target
  
• Shot an AIM-45C at 75 nm in PDSTT, kept lock till missile was 15 nm from target (broke with PLM), missile lost track, when TWS reacquired the track the missile started going after the target again even if the track on the TDI was not indicating the target beign shot at
  
• Shot an AIM-54C at 75 nm in PDSTT, kept lock till missile was 15 nm from target (broke with PLM and the shutted off radar), missile hit the target
  
• Shot an AIM-54C at 75 nm in PDSTT, kept lock till missile was 15 nm from target (broke by commanding Jester and the shutted off radar), missile hit the target
  

 

So the AWG-9 can put a trashed Phoenix back on track, even in STT mode? What is this wizardy? :huh:

 

[Spiceman]

 

I am not confusing the DL with link-4 as far as I know it should be on a diferent frequency as others have told me. I have said I am looking for the right answer here as some tell me one thing and others tell me another but there never seems to be documentation to back it all up.

 

They are certainly on different frequencies. If anyone tells you different, just point them to the DDD which has two dial selectors for the two TWTs, the radar TWT and the CW TWT (radar channel and missile channel).

 

[jojo]

 

How does the missile active command work from the rio pit? Is the signal in the radar emmission or something else?

Ie could you turn cold and then send the command are do you need to send the command 1st?

with stt the phoenix is semi active all tye way, can the go active command still work with that?

what happens if you have multiple phoenix in the air and you press tye button? Do they all go active or just the last 1 fired?

 

There is the intended functions described in HB manual...and there is how it works in DCS.

It looks like HB is struggling with ED API to get AIM-54 to work as intended.

 

The way it’s described in the manual, if you launch in STT, it’s a Fox 1 until impact. If you loose the lock, it won’t switch to active mode. It isn’t that clever.

When you launch in TWS, you should keep the targets within radar scan area. The radar will send “active command” to the missiles, which will be shown in the cockpit at TTI = 16s with targets flashing.

If you go cold before “active command” is sent by the radar, the AIM-54 won’t go active and is lost.

The active command is sent automatically, RIO can’t force it.

 

Off course you can also launch active from the missile release, but it’s rather intended for short range.

[UWBuRn]

Weird, sounds like a bit of cheating/workaround is going on but it's kind of ok - if you're paying attention it's almost like the missile has a 2-way datalink, since this is telling that the missile has reached active distance as opposed to just trusting the timer and the WCS to send the active command :)

 

Yeah, that's exactly what i taught of. As said, to me it's a decent compromise at least to know that the go active command (which i guess it's just not there, as i think it's under the hood still distance based) has been sent.

 

Right on the first obviously, and on the second, DCS does not simulate command channels ... that channel would have been dead, not to be used again so the DL would have never resumed - and importantly the active command would not have been sent AFAIK.

 

Yeah, i think at the current stage digging up dead channels is something we have to live with, i don't have high hopes of this getting addressed - feels like a very special edge case that should be cared in ED API - honestly i can live with it. PDSTT it's another story.

 

IMO HB made the workaround on the TTI, ED new missile API it's just not there yet, or not entirely.

 

 

[Harlikwin]

 

You need to read through the comments a bit beter I think. We are not discussing this from a position of complete ignorance. We know the radar modes and it seems like you are confusing fox 1's with fox 3's. A lot of the information posted seems to be from Wikipedia after googling SARH.

 

Thats what it sounded like you were doing from what I read.

[dundun92]

 

Where does HB state that the target should get a launch warning from PD-STT (SARH/DL). That would settle the argument don't you think and since I have not seen this when reading the HB manual so can you link it please? Thanks.

 

"In PD-STT (Pulse-Doppler Single Target Track) the AIM-54 will be launched in a pure semi-active mode and be guided in that mode all the way to target without going active. This means that the engaged target will get an immediate engagement warning through its radar warning receiver from the AN/AWG-9 as soon as the AIM-54 leaves the rail. Like in TWS the missile will loft if fired at range."

 

Is this not clear enough?

Link: http://www.heatblur.se/F-14Manual/weapons.html#aim-54-in-dcs

[eatthis]

 

There is the intended functions described in HB manual...and there is how it works in DCS.

It looks like HB is struggling with ED API to get AIM-54 to work as intended.

 

The way it’s described in the manual, if you launch in STT, it’s a Fox 1 until impact. If you loose the lock, it won’t switch to active mode. It isn’t that clever.

When you launch in TWS, you should keep the targets within radar scan area. The radar will send “active command” to the missiles, which will be shown in the cockpit at TTI = 16s with targets flashing.

If you go cold before “active command” is sent by the radar, the AIM-54 won’t go active and is lost.

The active command is sent automatically, RIO can’t force it.

 

Off course you can also launch active from the missile release, but it’s rather intended for short range.

 

apparantly the rio can manually activate them (ph act button). id love to know exactly how that works though, is the signal embedded in the awg 9 radar transmission? so i need to maintain radar contact for it to work?

if so is that contact with the target or just the missile?? if i lose tws lock the wcs will continue to update the target position via dead reckoning, does this mean the missile will still go to the postion the wcs thinks it is and then go active??