Recording acoustic signatures - how is it done?

[STURM]

Very curious as to how surface ships and subs record the acoustic signatures of other vessels. Is such equipment a standard fit on sonar suites or does it have to be ordered separately?

 

[oldsailor58]

Very curious as to how surface ships and subs record the acoustic signatures of other vessels. Is such equipment a standard fit on sonar suites or does it have to be ordered separately?

i know in the old days,(pre 1980) audio information was recorded on a multi track(>50) tape recorder using 1" magnetic tape that could record at speeds over 30 inches per second. equipment was sorta portable(2 man carry). with the advances in electronics, creating a multi channel digital record should be easy and the equipment briefcase size. i wear a hearing aid that has 2 microphones, has an 8 frequency equalizer, and samples what i hear at a 2 Mhz rate. it isn't much bigger than my thumbnail.

 

[gf0012-aust]

Very curious as to how surface ships and subs record the acoustic signatures of other vessels. Is such equipment a standard fit on sonar suites or does it have to be ordered separately?

There are a number of ways we do it. One is a fixed cage where the sub is sailed into the middle and then mapped

The solution I've been involved with was a conformal array which was moved along the hull and then the subs acoustic reflection image mapped

am niot too keen on expanding the detail on this for a number of obvious reasons

 

[gf0012-aust]

i know in the old days,(pre 1980) audio information was recorded on a multi track(>50) tape recorder using 1" magnetic tape that could record at speeds over 30 inches per second. equipment was sorta portable(2 man carry). with the advances in electronics, creating a multi channel digital record should be easy and the equipment briefcase size.

the proper fixed array solution is designed to take a complete sub - its huge
the mobile solution is about the size of a small crane and takes "forever" to use (in comparison)

we use acoustic arrays to map ballistics, 8-10 years ago we used laptops, now we use PDA sized devices - you can't do the same scaling to subs. suitcase sized devices are out.

 

[oldsailor58]

the proper fixed array solution is designed to take a complete sub - its huge
the mobile solution is about the size of a small crane and takes "forever" to use (in comparison)

we use acoustic arrays to map ballistics, 8-10 years ago we used laptops, now we use PDA sized devices - you can't do the same scaling to subs. suitacase sized devices are out.

the original question was about "recording the data". how one obtains the data is something that really shouldn't be discussed. i have not worked for the submarine service since 1980 and I am not sure what is still classified and what is not.

 

[gf0012-aust]

the original question was about "recording the data". how one obtains the data is something that really shouldn't be discussed. i have not worked for the submarine service since 1980 and I am not sure what is still classified and what is not.

technically you could record the data to any storage device large enough to receive the
output - but that usually co-resides on the appl which processes the data. they're kind of intrinisically linked

the cage is designed to take a sub the size of a Seawolf or 688I
I've used the other solution using a conformal array and a laptop.

I'm not going to discuss details of how and what is done to map the hull though