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Molon Labe · 10-07-05, 12:53 PM

I think you're getting suckered by the ambiguous contacts of the towed array. Whenever the towed array has receives a signal, it doesn't "know" what side it is coming in from, so the contact is displayed on BOTH sides of the array. So, when you're TA is centered on course 000, and you're scanning on your narrowband and a contact comes up on bearing 035, that same contact will also be displayed at bearing 325. Your task is to decide which of those bearings the contact is really on.

There are two ways you can settle this. The easiest, and least likely to be available, is to detect the contact on another sensor, like the Spherical or Hull array, or ESM.

The other way is to turn the boat. Once the TA completes its turn, one contact will be about where it was before the turn, the other will have moved really far. For example, if the boat above was turned to course 120, after the TA turns one contact may be at 035 and the other at 205. The one on 035 is the real contact (the 205 is just the "mirror" of 035 on the new course).

If you mark both contacts before the turn, you will be able to see one line moving radically during the turn. If you don't want to waste a tracker on a fake contact, you can scan the sonar during the turn, you will see one contact barely changing bearing, while the other one changes bearing significantly.

You can also check the TMA after the turn, if you didn't look at the sonar during the turn. The TMA line for both the real and fake contact during the turn will be off, but the TMA line after the turn will be close to the older ones, while the other one will be way off.

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Another thing to keep in mind is the Akula can shoot missiles that drop torpedoes, so a TIW from an Akula won't necessarily be in the same direction as the Akula.

10-07-05, 12:53 PM	#3
Molon Labe Silent Hunter Join Date: Jun 2004 Location: Along the Watchtower Posts: 3,810 Downloads: 27 Uploads: 5	I think you're getting suckered by the ambiguous contacts of the towed array. Whenever the towed array has receives a signal, it doesn't "know" what side it is coming in from, so the contact is displayed on BOTH sides of the array. So, when you're TA is centered on course 000, and you're scanning on your narrowband and a contact comes up on bearing 035, that same contact will also be displayed at bearing 325. Your task is to decide which of those bearings the contact is really on. There are two ways you can settle this. The easiest, and least likely to be available, is to detect the contact on another sensor, like the Spherical or Hull array, or ESM. The other way is to turn the boat. Once the TA completes its turn, one contact will be about where it was before the turn, the other will have moved really far. For example, if the boat above was turned to course 120, after the TA turns one contact may be at 035 and the other at 205. The one on 035 is the real contact (the 205 is just the "mirror" of 035 on the new course). If you mark both contacts before the turn, you will be able to see one line moving radically during the turn. If you don't want to waste a tracker on a fake contact, you can scan the sonar during the turn, you will see one contact barely changing bearing, while the other one changes bearing significantly. You can also check the TMA after the turn, if you didn't look at the sonar during the turn. The TMA line for both the real and fake contact during the turn will be off, but the TMA line after the turn will be close to the older ones, while the other one will be way off. --- Another thing to keep in mind is the Akula can shoot missiles that drop torpedoes, so a TIW from an Akula won't necessarily be in the same direction as the Akula.