TMA - Missing Variables?

[GSmith63]

Hi all. In reading the manual, the section on TMA includes a number of factors that increases the speed at which a target solution is likely to be produced - high bearing rate being an example. I think a couple of important factors might have been left out, unless they were later added after the manual was completed.

First, if the contact is held on both the bow sonar and the towed array, shouldn't this allow for a very rough triangulation that would narrow down the possible location of the contact?

Second, I've always heard that subs attempting TMA will do one or more course changes. This is supposed to help limit the number of possible contact locations provided by the bearing data, assuming that the target keeps a steady course/speed.

Are these two factors taken into account?

[MR_AUS]

Not sure about the increased solution speed because of the contact being picked up on the two sensors, however, getting a higher number (greater than 10) for your solution will increase the speed if you have it on both passive sensors.
For changing course, depth and speed, these will all assist decreasing the time taken for the solution to be locked in. Changing heading towards the contact (pointing the bow) will increase the bow sonar level and decrease the towed sonar level and vice versa. It will take a little time for these levels to adjust, but you can watch them change over time. Having a high number on both (above 10) will provide a better solution. Changing depth will also help. Moving above the layer, if present, and diving below the layer will increase solution too. Sometimes diving deep will assist. Obviously own ship speed will change the sensitivity of the sensors. Higher speed will "wash out" the sounds of the contact and slower speed will allow the sensors to isolate the sound of the contact against the background noise and that of your own ship moving through the water. Set the ship to run at ultra quiet (5kts or less, even come to a complete stop) and the solution speed will improve.
The last two ways to get a solution is to either use active sonar or surface sensors.
Going active is not advised as it will reveal your position (this will give you an almost instant solution if the contact is close enough, the range of active is much shorter than passive), but if you fire straight away, you may have the chance to turn and run. Don't forget to turn active off!
Surface sensors will also increase the solution. All of these are only useful for surface vessels or subs on the surface. These can also give the enemy a lock on your position, so use with caution. The periscope will give you a visual on the contact, lock in with the "I" key to laser range find and identify the target. The periscope also has a EMS sensor built in, but this mast is larger and has a larger radar cross section, so easier for the enemy to detect. The EMS mast will lock onto enemy radar and radio, giving an accurate bearing and range, less revealing to the enemy, but still detectable. Lastly, the radar mast. This is like active sonar for the surface, great to get a lock on your contact, but they will get you too. All of the masts will also can be visually seen and radar detected by patrolling helicopters and aircraft, so use only if needed.
The underwater tactics are always the best, but the role of a sub captain is to be calm and take their time and remain silent and undetected. The solution will come, subs are a waiting game.
Happy hunting!

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GSmith63!

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[GSmith63]

Thanks for the welcome everyone! Devs - Do you have any comments on my questions?

[Capt Jack Harkness]

Not a dev, however it's been mentioned numerous times by them that bearing rate is crucial to developing a quick solution, so yes, course changes can be very helpful. Speed can also help since it also drives bearing rate.

As for triangulating by using the TA and bow array together... My understanding is that the towed array (at least in '84) gives very poor bearing resolution so this probably isn't possible. Regardless, the game does not take any of this into account. Modern boats (Seawolf and newer) have flank arrays designed for triangulation, we'll see how that works when we get the Seawolf in our hands.

[XenonSurf]

The TMA logic in CW is missing an important aspect for enemy sub detection I think. I never get a good solution for subs that are more than 10 kyds away, so I almost never get a good solution for firing Sea Lance missiles that have precisely a minimum launching range of about 10 kyds. I have a very short firing window to fire them, just a few seconds, when subs leave that min. distance. I never have located subs at, let's say, 15-20 kyds, this should be possible however (and the contrary too: enemy subs detecting me at 15-20 kyds).

Lacking a precise TMA, I would highly welcome to be able to put a marker or plot a line on the tactical map so I can make a location preview of targets based on their course and speed. This would allow me to fire Sealances at calculated positions on the map without the need to have 100% TMA solutions for targets.

Using Sea Lances is quite better than launching a torpedo in order to keep your stealth profile, the launch noise can be located for a short time though. In CW, enemy subs have no idea where you are after launching Sealances and I don't think they hear the transient noise. You need more MK-50 impacts to destroy a sub.

Note: Sea Lance missiles are not in the vanilla game currently, only in mods . But they behave quite well and realistically IMO.

[GSmith63]

Originally Posted by Capt Jack Harkness

As for triangulating by using the TA and bow array together... My understanding is that the towed array (at least in '84) gives very poor bearing resolution so this probably isn't possible.

In '84 we are probably talking about a BQR-15 towed array, and open sources give its cable length as over 2,500 feet. Even with poor bearing resolution, I'd think that at the short tactical ranges we start with in CW, and a baseline of 2,500 feet, you should be able to get enough of a triangulation to really narrow the range/course/speed possibilities your bearing data is providing. Mind you, I'm not talking about a pinpoint triangulation off the two sonars, just something that should definitely speed up the TMA process.