That's an interesting find there Double R. More on it later.
A good place to look for information on ships of all types is from the
Historic Naval Ships Association.
Here, you'll find the
Radar Operators Manual If you look for the chapter "Specific Equipment" you'll find both SD and SJ radar headings. On page 4-SD-5 you'll find the heading "Performance", with
this as the SD's (Air Search) Reliable Range:
Large planes above 1,000 feet.......12-20nm
Small planes above 1,000 feet.......8-15nm
Low planes......... Not detected
Late war development of the SV Radar (taking the place of SD-1 Air Search improvements), can be found here at the
USS Pampanito site:
Maximum reliable range. (miles):
Bombers, at 30,000 ft........7.5
Bombers, at 10,000 ft........10
Fighters, at 10,000 ft.........12
Battleships.......................12.5
Cruisers...........................15
Destroyers.......................10
Submarines, surfaced.........7.5
The "Radar Operators Manual" also lists the SJ (Surface Search) performance on page 4-SJ-9:
Antenna: 33 Feet
Target..........................Maximum Reliable Range in Yards
BB, CV, Large auxiliaries............25,000 to 30,000/12.3nm-14.8nm
CA, CL, Medium auxiliaries..........20,000 to 25,000/9.8nm-12.3nm
DD, DE, DM, AV, PC, CG, etc......15,000 to 18,000/7.4nm-8.8nm
In another document of 1943 called
"Operational Characteristics of Radar Classified by Tactical Application, FTP 217" You can get another idea of radar range by looking up either SD or SJ radar.
You may say....."Well, this proves you're all wet Scurvy. You're ranges are too low!!"
My answer......it's been documented that these "performance ranges", even the "reliable" ones are from optimum conditions,
and are well
above true found ranges. Take a look at this document, the
"Radar and Submarine War, 1941-1945: A Reinterpretation" by Robert Dienesch......page 32 should be read carefully regarding SJ radar performance:
Pay attention to this authors footnote to that statement. His footnote points to another authors book by Norman Friedman, "
Submarine Design and Development",.....He states:
Cue in Double R's findings in the document "Enemy Contacts by U.S. Submarines, 1943 to End of War". You'll see SJ radar making first contact, on average, to be about 16,000 yards.....some as high as 22,000 yds. One as high as 30,000 by sub SS 304.
In the Hydrophone/Sonar area, there's not much of a definitive performance specifications as there is with Radar. Sound traveling in water is rated more in decibels than in specific range figures. I offer this site
"The Pacific War Online Encyclopedia". It states:
By far and away, the detection sensor that really has the edge is the visual! The "Enemy Contact" document reports having lookouts regularly detecting at ranges of 30,000 yards plus!! I couldn't help to see a pattern though....... that sub SS 304 that claimed they detected a radar contact at 30,000 yds was regularly finding 40,000 yard targets by its lookouts!?! They weren't the only sub who seemed to find things out at distances a little questionable. On Jan 10, 1944 and again on the 14th, sub SS 197 reported their lookouts spotted ships at 50,000 yards?? Either they had the sharpest crew in the Navy, or someone took a liking to inflating the numbers!?
Anyway, here's why I've got my radar sensors set as they are. And, its worth while to check some others as well.