Following a fast moving sub with towed array?

Pisces · 09-29-14, 03:24 PM

Why are you limited to a speed of 6 knots? If you are going that slow, and he is faster and moving away then it is simply impossible to close on him. At best you can match his course to reduce the relative motion, and postpone the moment you are loosing him on sensors. Hopefully he is coming towards you, then you can set a course to get in front of his path, but let him do the closing. If not then you must question your limitations and find ways to get a better tactical position.

If he is going fast, even if he is a sub, then his sensor sensitivity is reduced by his own noise. So you can afford to go a bit faster than you were previously. But how much is a tricky thing to gamble on. A balance of bravery and beware. Try to use depth to get higher cavitation speeds, and make use of how the soundlayer bends your sound away from him. The sprint and listen/drift technique ikalugin describes helps to get a bit higher average speed and make his TMA efforts more difficult (if he can hear you). But it is easy to over do it and get torpedoes fired at you if you are too cocky. Don't expect to be invisible under the layer.

The seabed contours can also help. Contrary to for example the SH3 andSH4 (don't know about SH5) the bottom actually stops the sound (can also reflect it further). You can hide behind a ridge or a seamount if it is steep enough. But this limits the paths you can choose, so might not be helpful.

If you want to identify which kind of sub or even surface ship it is you need to use the narrowband sonar with the towed, hull and bow sonar. Get a tracker assigned from each of them on it. (but it doesn't have to be at the same time) Each is sensitive in respectively low, middle and higher frequency. And each class emits a set of 5 frequencies that make it somewhat unique.To be able to detect the higher frequencies (which allow to narrow down to a specific class) it comes down to being slow/silent (the hull array is particularly sensitive to own speed noise) and being close enough. Also the number of blade-lines in the demon screen can help to narrow down the class. But you don't get all the blade-lines at far away range. You'll get more when you get closer or his signal is stronger. So the best identification is usually done when closer.

09-29-14, 03:24 PM	#1
Pisces Silent Hunter Join Date: Dec 2004 Location: AN9771 Posts: 4,904 Downloads: 304 Uploads: 0	Why are you limited to a speed of 6 knots? If you are going that slow, and he is faster and moving away then it is simply impossible to close on him. At best you can match his course to reduce the relative motion, and postpone the moment you are loosing him on sensors. Hopefully he is coming towards you, then you can set a course to get in front of his path, but let him do the closing. If not then you must question your limitations and find ways to get a better tactical position. If he is going fast, even if he is a sub, then his sensor sensitivity is reduced by his own noise. So you can afford to go a bit faster than you were previously. But how much is a tricky thing to gamble on. A balance of bravery and beware. Try to use depth to get higher cavitation speeds, and make use of how the soundlayer bends your sound away from him. The sprint and listen/drift technique ikalugin describes helps to get a bit higher average speed and make his TMA efforts more difficult (if he can hear you). But it is easy to over do it and get torpedoes fired at you if you are too cocky. Don't expect to be invisible under the layer. The seabed contours can also help. Contrary to for example the SH3 andSH4 (don't know about SH5) the bottom actually stops the sound (can also reflect it further). You can hide behind a ridge or a seamount if it is steep enough. But this limits the paths you can choose, so might not be helpful. If you want to identify which kind of sub or even surface ship it is you need to use the narrowband sonar with the towed, hull and bow sonar. Get a tracker assigned from each of them on it. (but it doesn't have to be at the same time) Each is sensitive in respectively low, middle and higher frequency. And each class emits a set of 5 frequencies that make it somewhat unique.To be able to detect the higher frequencies (which allow to narrow down to a specific class) it comes down to being slow/silent (the hull array is particularly sensitive to own speed noise) and being close enough. Also the number of blade-lines in the demon screen can help to narrow down the class. But you don't get all the blade-lines at far away range. You'll get more when you get closer or his signal is stronger. So the best identification is usually done when closer. Last edited by Pisces; 09-29-14 at 04:15 PM.