Submarine Noise and Signatures

[broncepulido]

Some days ago I saw Brad has reduced in the last iteration of the DB in one unit the sound value of the submarines in the DB.

I think is an usual change, I perceived it because in the previous iteration I was thinking about the sound value of the submarines and noting they are adjusted to the real values. This thinking was based mainly in the data published on the famous table of Submarines of the Russian and Soviet Navies:1718-1990, of Polmar and Noot, Naval Institute Press, Annapolis,1991.

Today, reckoning about it but not searching data about the topic, I've finded casually this page base on the mentioned table and parallel data of other books:

http://web.archive.org/web/20050309221955/...al/e_noise.html

If we take the values of the column Noise Level - discrete frequencies in 5-200Hz, divide it by 10, and multiply by 2.5 and round the result, we obtain in all the modern submarines represented in the DB almost the same noise values the DB has from the last iteration !!!

i.e. you can test it with the Los Angeles and 688(I) classes ...

Only some old boats and old Russian boats have greater values as rellected in the table

Very impressive.

[CV32]

Enrique .. you sir, are notably astute.

[broncepulido]

Enrique .. you sir, are notably astute.

[JMS]

Of interest, although not comparable:

 

http://www.foia.cia.gov/docs/DOC_000031626..._0000316265.pdf

 

Edited to add: they are comparable if applying the old criteria (substracting 100 Db) to the low frequency band