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Old 08-13-2019, 11:42 PM   #19
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Join Date: Feb 2018
Location: Kingston Canada
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Default A/A Mode & Sensor Configuration

Hi gents,

Been following your discussion with interest and just wanted to chime in to say that Sk000tch is providing you with some very sound advice. Based on my limited knowledge, I'd recommend that you do not get into the habit of turning your LTWS off as it limits what you can accomplish with your sensor package. More on that below if you're willing to read it all. And that brings me to my second bit of advice. This subject is rather complicated and the functions and interactions of radar and weapons systems takes some effort to understand. Do yourself a favor and study the material because even though it makes little sense the first time you read it, in time you will develop a deeper understanding of it.

To add to Sk000tch's comments I've included some material below that I posted today on the No.401 Sqn forum. If you really want to learn more, then read it all, if not, then just ignore the remainder of this post. Sorry it's long, but I can't find any shortcuts.

401 Squadron Forum

I've been hitting the "books" again after the most recent update to find out what has changed with target acquisition. It certainly seemed like something was broken, but the bug reports and various posts on the ED Forum point to a different scenario. Seems that we (I) have been learning radar target acquisition and sensor/datalink functions and integration within the context of a "work in progress" and what was becoming routine is now evolving beyond an incomplete model to something closer in function to the actual system. Prior to LTWS implementation and perhaps during further development of PLID, UCTR, Datalink etc, it was a simple matter to place the cursor on the target brick and manually acquire and then designate each via manual or AACQ. But now, with these other functions beginning to roll out of the DCS development factory, this "simplified" mode of target acquisition simply does not function as it did.

First, many have reported a failure to lock when placing the TDC cursor over a HAFU and trying to acquire/designate that as the L&S. It's happened to me many times and looks like the MC is directing the radar to scan a tight azimuth over the HAFU but then releases it and defaults the radar back to RWS with the cursor high and to the left. REASON: the HAFU symbol on your Attk Rdr display is likely a trackfile being provided to you by AWACS or another donor aircraft via Datalink but that your radar has not yet detected. Possible solution is to place your radar in SIL mode, enter SENSORS on your SA display and switch off SURV function (PB 15). This will clear the deck so to speak, so that you can then switch SIL off, and allow your radar to sweep and detect the targets.

Second, AACQ not acquiring new target. If you have designated your L&S via AACQ and want to back out to BVR mode in order to see and select another target on your Attk Rdr display, you must activate the undesignate switch. You also have the option of moving the SCS toward the Attk Rdr display while in AACQ to activate bump acquisition which will place a temporary exclusion zone around the original L&S while it performs a search for another target for ten seconds (note: this will be implemented in future updates). That's along time in a closing fight with missiles inbound, and by then your second target may have closed sufficiently to be outside of the gimble limits of your sweep. So after ten seconds the only target remaining may be the original L&S target (I've had this happen many times where the radar simply returns to the original L&S without every finding the second target). Remember to undesignate when you want to exit AACQ back to full BVR mode. Then you will see your original targets displayed on the Attk Rdr display.

Third. Since the latest update, manual acquisition of the L&S target via one depress of the TDC completes designation (as in fast acquisition) preventing you from acquiring a DT2 trackfile. I just learned after reading the radar material again, that since implementation of LTWS, that if you disable LTWS, the radar will lock a target with one depress of the TDC. In order to acquire a L&S target trackfile along with a DT2 trackfile, LTWS must be activated. With this configuration, you can then acquire your L&S target by placing the cursor back over the HAFU with star (L&S) and depressing the TDC a second time, or place the TDC cursor over the L&S and move the SCS toward the Attk Rdr display to activate AACQ. Hopefully, future DCS updates will enable Bump Acquisition via movement of the SCS toward the Attk Rdr display while in AACQ to seek and lock the next target in priority sequence. (Sorry gents, I had to edit this bit as I made an error in how to perform bump acquisition)

Read on if you want to get if from the original source:

5.3.1 Designation via TDC
Trackfiles can be designated by slewing the cursor over the undesignated HAFU symbol and depressing the TDC. This mechanization only applies to visible HAFU symbols (e.g. TWS, RAID, A/EL format, or RWS with LTWS selected). Attempting to designate a raw hit from VS or RWS (without LTWS selected) will instead immediately acquire it into STT. (that little bit of knowledge didn't stick the first dozen times, so maybe this time?)

When the cursor is slewed over an undesignated trackfile's HAFU, a TDC depression designates the trackfile as either the L&S or DT2. If no L&S has yet been established, then this first depression designates the target as the L&S. If a L&S trackfile designation already exists on another trackfile, then the depression designates the target as the DT2. Any previous DT2 designation on another trackfile is cleared. If a designation occurs on the L&S, the L&S is then acquired into STT.

When the TDC is depressed with the DT2 under the cursor, the DT2 is upgraded to the L&S designation and the previous L&S is demoted/re-designated as the DT2. This applies to both the Attack format and the AZ/EL format. Note that a TDC depression/release while over the L&S commands the Radar into STT acquisition on the trackfile as described in the preceding paragraph.

To summarize:

Designating a pre-existing L&S target, enters acquisition (STT) immediately
Designating a raw hit (no HAFU displayed), enters acquisition (STT) immediately
Designating an undesignated trackfile makes it the L&S. If another track was previously the L&S, the old track is made the DT2

5.3.2 Designation via Undesignate
Yes, it's a genuine oxymoron. Undesignate can be used for several designation functions, the behavior of which is dependent on whether or not a L&S or DT2 already exists (this has not been tested but I do know that the stepping function has not yet been implemented for the DCS F/A-18C:

Initial L&S Designation - When no L&S designation exists, the initial Undesignate activation makes the highest ranking trackfile the L&S.
Target Stepping - When the L&S exists, but not a DT2, the Undesignate switch allows stepping the L&S designation to other MSI trackfiles. With rapid selections of Undesignate, the desired trackfile can quickly be declared the L&S. In this rapid sequence, the MC steps the L&S in the order of rank, through the top eight trackfiles. (NOTE: virtually identical to the bump acquisition function)

Target Swapping - When a L&S and DT2 trackfile both exist, the Undesignate switch swaps the designations between the two (assuming none of the overriding conditions below hold true).

Other Radar functions that make use of Undesignate take precedence over the Designation functions as follows:

Exiting Auto Acquisition (AACQ)
Exiting Spotlight mode
Exiting FLOOD mode
Exiting ACM modes
In any of these cases, Undesignate first performs the aforementioned function and only then can it be used for designation functions.

5.3.3 Designation via Acquisition
If the Radar is commanded into STT by any means, the corresponding trackfile is always declared as the L&S if it was not already. For example a TDC designation from VS or RWS (without LTWS enabled), will immediately both declare the trackfile as the L&S and enter STT. Likewise, Fast Acq, AACQ, or ACM modes which all ultimately command STT, will accomplish the same thing. This guarantees that the L&S designation is applied to the desired trackfile even if the acquisition is not successful.


I ran another few tests with LTWS enabled and was able to acquire separate L&S target and DT2 using manual acquisition. But then after designating the L&S target and upon engaging with a couple of AMRAAM, I could find no quick reliable way to switch onto DT2. The only way that seems to work (sometimes) is to undesignate, wait a second or two for the radar to sweep, then move the cursor onto the second target and depress the TDC twice. It only worked once, when I took a few extra seconds before going defensive (total of 40 sec with a missile literally hundreds of feet away) and managed to get a lock. Every other time as I was evading missiles from the L&S target, I was unable to get a lock on the second aircraft. I would put the cursor over the HAFU, double tap the TDC depress and nothing would happen. I only ever got the second aircraft in ACM mode with the AIM 9x.

I only experienced one event when the radar entered a narrow azimuth sweep over a HAFU that I had completed Mode 4 interrogation and which clearly showed a full Hostile reading. In this case I had set my radar to 80 nm as usual, but changed the bar setting to 2 with the sweep setting set to 140 degrees. I could not obtain a lock via manual or AACQ.

Last edited by No.401_Speed; 08-14-2019 at 01:15 PM.
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