ShouldnÂ´t Active Sonar provide target depth?

Fandango · 07-07-05, 11:39 AM

Antonio,

that's DEPTH SONAR, I'm afraid...that is, the sonar that's on boats ranging from private pleasure to big ships...

compressioncut · 07-07-05, 12:36 PM

No, it shouldn't. LF/MF search and attack sonars only provide range information, although it's possible to roughly estimate depth based on conditions and intel. You can calculate depth if you get a Lloyd's Mirror effect on a lofargram, but that's not active sonar.

Depth isn't a particularly important reading because a sub is only going to be in a narrow depth slice, of like what, 0-1500 feet? You can then narrow that down based on what you know of the threat, bathythermographic conditions, sonar performance, and et cetera. It's not like an airplane which can be 1-60,000+ feet.

Caseck · 07-09-05, 08:54 AM

No, that's not true. (IRT Pleasure boat sonar...)

Sonar should be able to tell depth before 1st CZ.

WWII+ sonar research paper:

http://jproc.ca/sari/index.html

amrcg · 07-15-05, 04:36 PM

[quote="Caseck"]No, that's not true. (IRT Pleasure boat sonar...)

Sonar should be able to tell depth before 1st CZ.]

So, you are saying that the active sonar display/model in SC/DW is lacking compared with the real world use of active sonar...?

Cheers,
Antonio

northfromhere · 07-16-05, 10:20 AM

Like said; Only for "shorter" distances can you get correct readings. Both active and passive devices are able to correctly place the bearing of a signal, given the distance and conditions are within the equipment limits. Thats one way a torpedo seeker centers on and/or intercepts a target.

Caseck · 07-20-05, 04:52 PM

Here's my reference:

http://jproc.ca/sari/asd_et2.html

An array of transducers can determine depth with active sonar. They can simultaneously determine angle and range. (=depth)

This stuff predates most modern LF sonars, but these WWII active sonars could give depth, and even the aspect you were looking at the sub from.

I'd have to look at modern LF sonar construction, but I do believe they are also arrays of small transducers, so they should have little problem discerning depth.

I don't see how depth could be determined beyond the 1st CZ, but I'm not a navy guy. I may be wrong there, but that's my guess.

Here's where this guy talks operations about modern variable depth arrays... Cool stuff!

http://jproc.ca/sari/asd_mod.html

So what I'm saying is, yes. DW is nerfing EVERYONE'S sonar. To an extent.

07-07-05, 11:39 AM	#1
Fandango Officer Join Date: Sep 2001 Location: Trieste, Italy Posts: 236 Downloads: 0 Uploads: 0	Antonio, that's DEPTH SONAR, I'm afraid...that is, the sonar that's on boats ranging from private pleasure to big ships... __________________ The true worth of a man is to be measured by the objects he pursues. - Marcus Aurelius

07-07-05, 12:36 PM	#2
compressioncut Loader Join Date: Jun 2003 Location: Canada Posts: 90 Downloads: 5 Uploads: 0	No, it shouldn't. LF/MF search and attack sonars only provide range information, although it's possible to roughly estimate depth based on conditions and intel. You can calculate depth if you get a Lloyd's Mirror effect on a lofargram, but that's not active sonar. Depth isn't a particularly important reading because a sub is only going to be in a narrow depth slice, of like what, 0-1500 feet? You can then narrow that down based on what you know of the threat, bathythermographic conditions, sonar performance, and et cetera. It's not like an airplane which can be 1-60,000+ feet. __________________

07-09-05, 08:54 AM	#3
Caseck Torpedoman Join Date: Mar 2005 Location: CONUS Posts: 116 Downloads: 17 Uploads: 0	No, that's not true. (IRT Pleasure boat sonar...) Sonar should be able to tell depth before 1st CZ. WWII+ sonar research paper: http://jproc.ca/sari/index.html

07-15-05, 04:36 PM	#4
amrcg Swabbie Join Date: Jan 2004 Posts: 9 Downloads: 0 Uploads: 0	[quote="Caseck"]No, that's not true. (IRT Pleasure boat sonar...) Sonar should be able to tell depth before 1st CZ.] So, you are saying that the active sonar display/model in SC/DW is lacking compared with the real world use of active sonar...? Cheers, Antonio

07-16-05, 10:20 AM	#5
northfromhere Swabbie Join Date: Feb 2005 Posts: 8 Downloads: 0 Uploads: 0	Like said; Only for "shorter" distances can you get correct readings. Both active and passive devices are able to correctly place the bearing of a signal, given the distance and conditions are within the equipment limits. Thats one way a torpedo seeker centers on and/or intercepts a target.

07-20-05, 04:52 PM	#6
Caseck Torpedoman Join Date: Mar 2005 Location: CONUS Posts: 116 Downloads: 17 Uploads: 0	Here's my reference: http://jproc.ca/sari/asd_et2.html An array of transducers can determine depth with active sonar. They can simultaneously determine angle and range. (=depth) This stuff predates most modern LF sonars, but these WWII active sonars could give depth, and even the aspect you were looking at the sub from. I'd have to look at modern LF sonar construction, but I do believe they are also arrays of small transducers, so they should have little problem discerning depth. I don't see how depth could be determined beyond the 1st CZ, but I'm not a navy guy. I may be wrong there, but that's my guess. Here's where this guy talks operations about modern variable depth arrays... Cool stuff! http://jproc.ca/sari/asd_mod.html So what I'm saying is, yes. DW is nerfing EVERYONE'S sonar. To an extent.