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shipkiller1 · 07-12-17, 02:27 PM

Passive TMA can be a hard thing to do, but it is nothing but a geometry problem. Sometimes with very little data.

When you first pick up a contact, the first thing that is determined is the bearing rate and direction of relative motion. If tactically feasible, you change course across the Line of Site (LOS) and you try to drive the bearing rate. The first one or two OS maneuvers nails down the range to a very good 'ball park' figure, to something that will be 'tuned' over time. The next maneuvers nail down the Target Course (Ct) and Target Speed (Dmht). Sonar can help a great deal if they can pickup some specific target parameters. On a surface contact, this is almost always the case. Dmht is easy with a surface contact. Historical operational data helps keep it in the ball park if you do not have the aural clues...

Solution accuracy is determined after each course change. Does the expected incoming bearing match the solution? but more important, does the bearing rate match?? If not, then you have to adjust your solution for a better fit. This is why on a quiet contact, you may take a couple of hours to get a firing solution and put the boat into the proper firing position.

The problem with bearing data accuracy depends on the frequency of the incoming energy. The higher the frequency, the smaller the beam-width (more accurate), conversely, the lower the freq, the larger the beam-width so there is lots of bearing inaccuracies. This has a lot to do with sonar system design and we will not get into this at all.

The 1.05b update incorporated your submerged contacts counter firing...

This is more like real life... so, you have to think about your firing position with respect to evading incoming fire. You may have to evade and re-position OS to press the engagement.

I personally like not having to do any hardcore TMA like you did in the 688i game. That game was just not realistic to do. Oh, it was somewhat realistic but 688i was essentially boring... you spent a long time doing TMA and all the other things that had to be performed. In real life, you had 30 people doing all those things but in 688i, it was all you... You got rushed, you missed stuff.

I think Cold Waters is much more enjoyable..

07-12-17, 02:27 PM	#12
shipkiller1 Electrician's Mate Join Date: Jun 2017 Posts: 136 Downloads: 5 Uploads: 0	Passive TMA can be a hard thing to do, but it is nothing but a geometry problem. Sometimes with very little data. When you first pick up a contact, the first thing that is determined is the bearing rate and direction of relative motion. If tactically feasible, you change course across the Line of Site (LOS) and you try to drive the bearing rate. The first one or two OS maneuvers nails down the range to a very good 'ball park' figure, to something that will be 'tuned' over time. The next maneuvers nail down the Target Course (Ct) and Target Speed (Dmht). Sonar can help a great deal if they can pickup some specific target parameters. On a surface contact, this is almost always the case. Dmht is easy with a surface contact. Historical operational data helps keep it in the ball park if you do not have the aural clues... Solution accuracy is determined after each course change. Does the expected incoming bearing match the solution? but more important, does the bearing rate match?? If not, then you have to adjust your solution for a better fit. This is why on a quiet contact, you may take a couple of hours to get a firing solution and put the boat into the proper firing position. The problem with bearing data accuracy depends on the frequency of the incoming energy. The higher the frequency, the smaller the beam-width (more accurate), conversely, the lower the freq, the larger the beam-width so there is lots of bearing inaccuracies. This has a lot to do with sonar system design and we will not get into this at all. The 1.05b update incorporated your submerged contacts counter firing... This is more like real life... so, you have to think about your firing position with respect to evading incoming fire. You may have to evade and re-position OS to press the engagement. I personally like not having to do any hardcore TMA like you did in the 688i game. That game was just not realistic to do. Oh, it was somewhat realistic but 688i was essentially boring... you spent a long time doing TMA and all the other things that had to be performed. In real life, you had 30 people doing all those things but in 688i, it was all you... You got rushed, you missed stuff. I think Cold Waters is much more enjoyable..