SCXIIC:How to correct the errors of sonar classification?

[sonar732]

Originally Posted by Stanny

I always assign trackers in broadband only.I use narrowband for classification purposes.I think,that if contact is invisible in broadband,there will be lots of problems tracking it in narrowband.For example,you may not be able to distinguish the bearing ambiguity or loose the contact while trying to do so.I prefer changing course from time to time,in order to scan different fields with towed array in broadband.I noticed,that course changes of ownship "prevent" weak contacts from escaping.

If you assign a tracker on a faint 50 hz tonal in NB, you'll have a better chance of detecting it earlier and a first shot probability on the platform. Think of it this way...you are looking at BB. Nothing is showing up in your STA waterfall, but you have a very faint line in ITA if you are lucky. There isn't a good enough SNR rating, so BB won't allow a tracker to be placed. However, if you go to NB, change your frequency to 100hz and place a tracker on the 50hz, you not only know that it's more than likely a sub, but also after a few speed, depth, and course changes, have a decent TMA reading when all you'd find out in BB is..."I know something is out there...don't know how far, but I know it's there"

[Stanny]

Originally Posted by sonar732

If you assign a tracker on a faint 50 hz tonal in NB, you'll have a better chance of detecting it earlier and a first shot probability on the platform.

Many thanks,I will give it a try.And what about TMA in this case?I think,it is worth launching torpedoes immediately after I get the very preliminary firing solution.

I have already made a conclusion,that the longer you try to calculate an excellent TMA solution,the less chances you have to hit the target,actually.

[sonar732]

Originally Posted by Stanny

I have already made a conclusion,that the longer you try to calculate an excellent TMA solution,the less chances you have to hit the target,actually.

Do you use the autocrew or manual TMA? I'll admit that I haven't mastered TMA yet and use the autocrew. So, with that being said...I've seen my TMA jump 15k-20k yards after receiving a new solution. There are websites out there that suggest you have your torpedo presets at every 5k-10k yards to cover this possibility.

Why in the world would you do that? In the picture perfect world, the contact you launched those three torpedos might stay along the same course...but more than likely not. So, you've just wasted three fish going down the same bearing going after something that took an evasive 45-90 degree turn away from the projected path.

Now he knows your general bearing and if his UUV got a good sniff of your torpedos early, he can launch a spread at you assuming that you have cleared dantum, he'll ignore the countermeasures you launched and utilize snapshots with a 5 degree difference.

One of strategy that I've seen is there will be a torpedo with the standard 75% range on snake pattern, then another will be either darn close or right on the exact TMA range with circle to cover the escape route.

[Stanny]

Originally Posted by sonar732

Do you use the autocrew or manual TMA?

I am using manual TMA as well as all other Seawolf's stations.I usually have no problems with working up a TMA firing solution if target keeps a steady course.

[Stanny]

I decided to follow sonar732's advice and turned on TMA and fire control autocrews.Detected Akula again on 50 Hz narrowband towed array and launched several torpedoes at her.This time fortune was on my side.

Here is a screenshot of sunk Akula-I "Narval":



So,I can make a conclusion,that those weak contacts should be fired upon immediately after detection.

[sonar732]

Glad that I could help you out! What was the range which you detected the Akula because the screenshot looked like they were pretty close to you.

[Stanny]

Originally Posted by sonar732

What was the range which you detected the Akula because the screenshot looked like they were pretty close to you.

I took a screenshot a bit later,however,the actual distance was about 12000-13000 yards or maybe even less.I should notice,first torpedoes lost their wires and missed,and Akula had been hit while making an evasive maneuvering with other couple of MK-48 Adcap Mod 5's.I spent four torpedoes for sinking this sub.

I think that main idea in engagements of such dangerous subs as Akulas,with their extremely low noise signatures is quick detection at 50 Hz narrowband and rapid firing at them,until they go down,initially.

[Captain Nemo]

Originally Posted by sonar732

If you assign a tracker on a faint 50 hz tonal in NB, you'll have a better chance of detecting it earlier and a first shot probability on the platform. Think of it this way...you are looking at BB. Nothing is showing up in your STA waterfall, but you have a very faint line in ITA if you are lucky. There isn't a good enough SNR rating, so BB won't allow a tracker to be placed. However, if you go to NB, change your frequency to 100hz and place a tracker on the 50hz, you not only know that it's more than likely a sub, but also after a few speed, depth, and course changes, have a decent TMA reading when all you'd find out in BB is..."I know something is out there...don't know how far, but I know it's there"

Sonar732 has hit the nail on the head. I believe the SCX mod made detecting subs that are a long way off or are very stealthy much harder to detect in broadband. However, using the techniques described in narrowband you will detect subs much earlier and sometimes long before they appear in broadband. Since having an LCD monitor though, I have found it harder to use narrowband in this way which is a pity, my old CRT monitor was much better at showing faint tonals in narrowband.

Nemo