Why not a floating towed array?
 

Why do sub not have a floating towed array? The ones in real life sink below the depth that the sub is travelling at to be able to hear other submerged contacts that may be behind them or below them at great depths. BUT, when there is a convergence zone and you pass below it you can now no longer hear what is above you in passive sonar. Things just vanish from the screen once you pass that 'specific' depth. So my question is why not have a towed array that floats upwards to be able to hear what's above. Of course this would require travelling at slow slow speeds as to not "drag" the array in a straight line behind the sub much like the standard array does when going at high speed. The purpose when using one is to go slow and let it sink to be able to hear what is deep. I want one that will float to hear what is above, similar to the floating wire for picking up radio messages safely.

You know, I vaguely remember reading something once about variable depth arrays for surface ships once, where a ship can adjust the depth of the TA independent on ship speed...

... don't remember where I read it though...

... maybe they do actually have something like this but its just so super secret no one knows about it.... :hmm:... who knows what's really out there.

Damn, did I give you a million dollar idea? If I did, please spare a few bucks to me :-j

The SURTASS is like this, but is only employed on a special "rig" of a boat.


However, the only reason for a towed array to have a positive buoyancy (which is negative in the database, btw) is to reverse the "dip below the layer" scenario.

on a surface ship there's not much reason to have something like that.. just reduce the length of the towed array (reel it in) or speed up and that solves the problem. for subs it would be a nice thing to have.

USN obviously disagrees...

It's a really difficult engineering problem to have an array that can both float and sink.

I don't think so... I mean, all that it would require is some kind of ballast tank. Of course.. this would make is rather large.

Perhaps they could just use 2 towed arrays. One with negative bouyancy, and one with positive bouyancy. Reeling in and out would adjust their depths.

I see what your saying. You think that it would naturally be heavy since you are comparing it to all the sensors in the standard towed array that weigh that array down.

All this "floating" array would require is a "special" buoy connected to the end of the floating radio wire. This bouy would have sensors built into it with a 360 degree scope with passive sonar capabilities. This could be wired and transmit the data into the submarines sonar suite (just like the stanard towed array does) and allow the sonar operator to see what is above a thermal layer without the sub having to surface above that layer. Rememeber, it would be better to have a thin line(cable) with a small buoy connected to it at the top(similar to a helium inflated balloon) than an entire submarine risk being detected by passing that layer. The smaller and quieter an object is the harder it is for it to be heard underwater.

Your basically describing a UUV.

Not really. The UUV is more like a torp that goes out and snuffs out the enemy down the road and reports back to the platform sub that hosts it what is beyond.

I am talking about the 'RADIO WIRE' and connecting a special buoy to it that can be reeled out like the 'RADIO WIRE' that floats towards the surface but to be used to just cross over or past the thermal layer threshold that the platform or host sub is below to be able to hear what is above. I know this can be done with the UUV but the UUV can not be reeled back in like the 'RADIO WIRE' or towed array wire. Using a UUV's would be costly since they can only be used once and dangerous since they do emit some noise as they travel through the water. A floating wire with a balloon shaped buoy that has a passive sonar sphere within it would be completely quiet and could be reeled back in for multiple uses making it more cost efficient and a lot more safe to use.

Yes lets make the highly sensitive and expensive sonar float up to the surface where its nosier and can be cut by passing merchant traffic... :roll:

Just to be used to get above the "THERMAL LAYER", not to go up to the surface. Most thermal layers are quiet deep and no merchant has a draft that goes down the low.

But most US Subs operate above the layer. Or at least thats what I've read.

Here's the concept for anyone who is confused about what I am saying. I am not the best artist in the world so forgive my feeble attempt at drawing. It's hard to draw on the PC.

The top red arrow points to the ball connected to the radio wire or any wire that will float and also allow for the data to be passed down into the host submarine. The ball has a spherical array within it similar in par to the sphereical array at the bow of most submarines, only much smaller and lighter weight. It is designed to go just above the thermal layer so that the sub below the layer can hear what is above it without having to rise above the layer and become an easier target for surface ships or other subs that may be lurking above that layer.

http://www.jtiz.net/SubSerpent/concept.JPG

The red arrow at the bottom points at a standard towed array cable that is heavy and sinks. This array cable is filled with tiny little sensors that allow subs to hear what's below and behind them at slow speeds.