FM Sonar in SH5, or a potential mod?

MikeVictor · 01-01-10, 12:07 AM

I'd like to see FM sonar added to the tench class subs, like the Torsk and Sea Cat.

This was developed late in the war and was used to identify mines and sub-nets protecting harbors and the Sea of Japan.

This is a document describing it in some detail, page 263 to the end of the chapter:

http://www.hnsa.org/doc/sonar/chap14.htm#pg263

And here is some info about how it was used in the Pacific:

USS SEA CAT (SS-399)
SHIP'S HISTORY
Researched by: Robert Loys Sminkey
Commander, United States Navy, Retired

"On the west coast of the United States, scientists from the University of California based at San Diego tackled the problem of submarines detecting and avoiding submerged minefields. During 1944, they tested several experimental "breadboard" sonar models capable of doing just that on USS S-34 (SS-139) and USS Redfin (SS-272). The most successful sonar set tested was a frequency modulated (FM) sonar that produced a characteristic ringing echo from mines and similar objects, and, accordingly, that sound was described as being "Hell's Bells."

The prototype of this equipment, the QLA, was sent on patrol with USS Spadefish (SS-411) and showed so much promise that additional sets were ordered on a rush basis from the laboratory and the Western Electric Company. They were installed on the boats of the so-called Hellcat wolf pack that penetrated Tsushima Strait in June of 1945 and rampaged through the Sea of Japan. Despite the success of this exploit, submariners were understandably unenthusiastic about picking their way through minefields.

The QLA was good only at short ranges...about a quarter of a mile...and suffered from the usual limitations of sonars under less-than-perfect water conditions--and there was always the possibility of sideswiping one mine while maneuvering to avoid others. Because USS Sea Cat was a potential candidate for patrols in the Sea of Japan, Frequency Modulated QLA sonar equipment was installed in her prior to her fourth war patrol."

Mike

01-01-10, 12:07 AM	#1
MikeVictor Seaman Join Date: Feb 2008 Location: Alexandria, VA near Washington DC, USA Posts: 36 Downloads: 407 Uploads: 0	FM Sonar in SH5, or a potential mod? I'd like to see FM sonar added to the tench class subs, like the Torsk and Sea Cat. This was developed late in the war and was used to identify mines and sub-nets protecting harbors and the Sea of Japan. This is a document describing it in some detail, page 263 to the end of the chapter: http://www.hnsa.org/doc/sonar/chap14.htm#pg263 And here is some info about how it was used in the Pacific: USS SEA CAT (SS-399) SHIP'S HISTORY Researched by: Robert Loys Sminkey Commander, United States Navy, Retired "On the west coast of the United States, scientists from the University of California based at San Diego tackled the problem of submarines detecting and avoiding submerged minefields. During 1944, they tested several experimental "breadboard" sonar models capable of doing just that on USS S-34 (SS-139) and USS Redfin (SS-272). The most successful sonar set tested was a frequency modulated (FM) sonar that produced a characteristic ringing echo from mines and similar objects, and, accordingly, that sound was described as being "Hell's Bells." The prototype of this equipment, the QLA, was sent on patrol with USS Spadefish (SS-411) and showed so much promise that additional sets were ordered on a rush basis from the laboratory and the Western Electric Company. They were installed on the boats of the so-called Hellcat wolf pack that penetrated Tsushima Strait in June of 1945 and rampaged through the Sea of Japan. Despite the success of this exploit, submariners were understandably unenthusiastic about picking their way through minefields. The QLA was good only at short ranges...about a quarter of a mile...and suffered from the usual limitations of sonars under less-than-perfect water conditions--and there was always the possibility of sideswiping one mine while maneuvering to avoid others. Because USS Sea Cat was a potential candidate for patrols in the Sea of Japan, Frequency Modulated QLA sonar equipment was installed in her prior to her fourth war patrol." Mike