reported AI vs player lock and launch warning for Patriot and SA-10B

[Mad_Shell]

What we observe in DCS:

A player engaged by a Patriot / SA-10B will see a lock alert on the RWR, and a launch alert as soon as a missile is launched.

An AI engaged by a Patriot / SA-10B will not react until the incoming missile is around 20 km away.

 

What open sources say:

The FM-44-15-1 manual (Distribution statement A: approved for public release, distribution is unlimited) for the Patriot indicates that:

"The missile is command-guided by radar to a point just prior to intecept. It is at this point that the unique TVM guidance mode begins. In the TVM mode, the radar set sends out a special waveform that illuminates the target. The radar sends an encoded uplink message to the missile that commands the missile to open its receiver for detection of the TVM waveform energy reflected from the target. The missile then encodes and sends boresight errors via downlink message back to the radar. Guidance computations are then made by the WCC and sent back through the radar to the missile via uplink message. This process continues until intercept."

It is very clear that the target should not have any launch warning until a few seconds before impact when the target is illuminated. Since the AN/MPQ-53 radar used by the Patriot to guide the missile is a PESA radar capable of track-while-scan, it is most probable that the target has no lock alert on its RWR at any moment, even when the missile is being command guided toward the target before the final illumination phase.

 

For the SA-10B we have in DCS (using the 5V55R missile), a very similar system is used, as described in the book "Невский бастион - Зенитная ракетная система С-300" (page 17)

"The missile 5V55R employs an improved radio-command guidance method for targeting. This method combines radio-command guidance in the initial and middle stages of the trajectory with the "target tracking through the missile" method in the final stage. Guidance commands for the 5V55R missile are generated based on the coordinates of the target and the missile measured by RP, and the target tracking data from the onboard radar sight of the SAM – a method similar to that used in the American "Patriot" system."

The book "THE RUSSIAN S-300 AND S-400 MISSILE SYSTEMS" also mentions midcourse commands and a final TVM guidance for the 5V55R missile.

We can see that it's actually the reaction of the AI units (only reacting when the missile is about 20 km away) that is more realistic than the players having a lock warning then a launch warning as soon as the missile is fired.

Now that we know that the target illumination begins at a predetermined range for these systems, do we have any clue about what this range could be?

Yes, but only an indirect one! In the "'Review of Defence Annual Report 2002-03: Analysis of Department of Defence Responses" document, it is written about the 9M82 and 9M83 missiles used in the SA-12 (developped at the same time period as the SA-10B):

"During midcourse flight the missile employs inertial navigation with the option of command link updates. In the former mode it transitions to its semi-active homing seeker during the final 10 seconds of flight, in the latter three seconds before impact – a technique preferred for heavy jamming environments."

Even if the guidance method is slightly different, it gives a good insight at where the technology stands at this period: with midcourse updates from the radar (as it is the case with the 5V55R missile), the missile only needs the target to be illuminated for 3 seconds before impact!

If you've read unitil there, you definitely seem to be interested into this subject, and I hope you'll enjoy the documents I cite or join

FM44-15-1Pt1(87).pdf Review of Defence Annual Report 2002-03 Analysis of Department of Defence Responses.pdf

Edit: this bug is linked to the broader problem with AI and radar guided missiles:

 

Edited September 9, 2024 by Mad_Shell

[Dragon1-1]

Neither SA-10 nor Patriot should set off launch warnings on RWR, but in both cases the search mode of the FCR is not very good, and in any case, the FCR is not turned on until the battery is ready to engage (otherwise you risk eating a HARM). What I've heard is, if you see a "10" on RWR, assume you've been launched at. That is your launch warning, and while the RWR won't raise hell about it, you'll live longer if you start defending right when the FCR goes on. 

So it's the AI behavior that is unrealistic, but the player getting RWR launch warning when the battery actually launches is wrong, too. Those SAMs seem to have been extrapolated from older systems such as SA-2, but a modern SAM like the SA-10 or Patriot can be a lot more sneaky. Another thing is, AI probably shouldn't react to the missile at all, since if it gets you, it'll be coming too fast for you to get tally on it. I suspect it's a leftover from the A-10, which assumed an MWS (which could pick up the missile a moment before impact).

[Mad_Shell]

7 minutes ago, Dragon1-1 said:

Neither SA-10 nor Patriot should set off launch warnings on RWR, but in both cases the search mode of the FCR is not very good, and in any case, the FCR is not turned on until the battery is ready to engage (otherwise you risk eating a HARM). What I've heard is, if you see a "10" on RWR, assume you've been launched at. That is your launch warning, and while the RWR won't raise hell about it, you'll live longer if you start defending right when the FCR goes on. 

So it's the AI behavior that is unrealistic, but the player getting RWR launch warning when the battery actually launches is wrong, too. Those SAMs seem to have been extrapolated from older systems such as SA-2, but a modern SAM like the SA-10 or Patriot can be a lot more sneaky. Another thing is, AI probably shouldn't react to the missile at all, since if it gets you, it'll be coming too fast for you to get tally on it. I suspect it's a leftover from the A-10, which assumed an MWS (which could pick up the missile a moment before impact).

When I said that the AI reaction was more realistic, I was talking about the RWR only, which seems to only indicate a launch warning in the terminal phase for them. Of course any semi competent pilot would anticipate a launch as you said. But that also supposes to have perfect ELINT. The SA-10 radar can switch between thousands of different frequencies, many only used in war time so that the enemy has never encountered them. I suspect quite a few radars show as "U" on RWR in real life...

Edited February 21, 2024 by Mad_Shell

[Kvek]

It's imperative an update to SAM logic. Right now in DCS, SAM work the more simplistic way. Always launching at max range, constantly emitting, zero communication between batteries, IADS not at all, no configuration through ME, SA-5 has wrong search radar, no reveatment, maps focus on churches but not a single sam site is modeled (sinai being the exception), etc.

Thank you Mad_Shell, very interesting information and nice documentation. I hope ED starts giving some attention to SAM/SEAD

[Whiskey11]

14 hours ago, Kvek said:

It's imperative an update to SAM logic. Right now in DCS, SAM work the more simplistic way. Always launching at max range, constantly emitting, zero communication between batteries, IADS not at all, no configuration through ME, SA-5 has wrong search radar, no reveatment, maps focus on churches but not a single sam site is modeled (sinai being the exception), etc.

Thank you Mad_Shell, very interesting information and nice documentation. I hope ED starts giving some attention to SAM/SEAD

Syria has a lot of SAM sites modeled... some better than others.  For instance, the Homs SA-5 exists... but it's wildly inaccurate compared to the real site. 

 

There is an SA-2 site west of Tabqa which never existed IRL...

 

Those are two easy examples. 

[Oceandar]

SA-10 launch without warning........I can see the horror lol.

[Mad_Shell]

23 hours ago, Oceandar said:

SA-10 launch without warning........I can see the horror lol.

But you will get a warning! About 5 or 10 seconds before impact 

[Mad_Shell]

I allow myself to bump this report since it hasn't been aknowleged by ED or a tester yet.

[ACS_Dev]

Good research effort!

[Kvek]

Please, take a look at this interesting report

[Mad_Shell]

Edited the first post to link it to my report about the AI and radar guided missiles bug.

But yeah, it's a bit disheartening to spend so much time doing research and not even have an answer after 6 months.

[Kvek]

For the moderators, please take a look to this great information presented.

[Mad_Shell]

@NineLine @BIGNEWY

Can you tell me if this is known issue by ED, as I've reported this almost a year ago?

Thanks

[Flappie]

Hi @Mad_Shell. This issue has been reported internally for several years. I'll add your findings to the internal report.