What are the meaning of these lines?

[Q3ark]

I think the small one you have labeled as visibility is the active sonar, where they can ping you. The next one up is the passive sonar (he can't here you from behind because of his engines) and the next one i'll have to guess at radar, I don't think it is the visual range as passive sonar can hear stuff from further out than can be seen.

Hope this helps matey

[Berinhardt]

I'm not sure that Japanese DD's had radar - usually only capital ships.

I always took the lines to be active sonar, passive sonar, and visual range (moving outward, smalllest to largest)

Just my 2 cents - could be completely wrong.

[JonB]

Yeah, that sounds likely, m8. Just a bit funny how nobody seems certain about it. I´ve tried locate info about this on their website, manuals etc but I´ve missed it or they havent mentioned it, I dunno...

[mcarlsonus]

The Japanese had Type 21 and 22 radar sets deployed on destroyers from August, 1943 ('44 for the 22). These were the only surface detection units available, if memory serves. IJN, etc., units were reluctant to use the sets as they were concerned about the enemy's ability to use the signal to successfully triangulate their positions.

[old_tex]

Yup, Active SONAR, Hydrophone, Visual. If you are submerged and a Tin Can comes into range, listen for his PINGING. When he gets within range as depicted by the smalled semi-circle, you will hear his pings. Otherwise, no. That's why you can possibly sneak up on him from behind (submerged). His prop noise inhibits his hearing, just like yours does.

Same scenerio applies to aircraft. Generally, the higher they are flying the bigger the viewing circle. However, you are also harder to spot. The faster you are running- Flank to Slow, the more of a wake you leave and that changes your visibility to the aircraft. Just because you are inside the viewing circle doesn't mean that he is automatically going to see you. Old_tex

[Capt. Green]

silly question from a newbie - how do you get those lines?

[SteamWake]

Originally Posted by Capt. Green

silly question from a newbie - how do you get those lines?

Zoom in the map and click on the 'target' the circles will appear. They will dissapear if you click anywhere else on the map. At one time some mods removed these lines but they snuck back in. Personally I dont think they should be there to leave a shadow of a doubt.

Outler line is visual, second one in is passive, third one is active.

Note that the 'active' shows up regarless of wether or not the ship is fitted with active gear.

Furthermore the pattern appears to be the same regardless of what type of ship. Now a ship with an 80 foot tall super structure would have a lot more visual range than an old split freighter.

But it is what it is.

[tater]

Originally Posted by mcarlsonus

The Japanese had Type 21 and 22 radar sets deployed on destroyers from August, 1943 ('44 for the 22). These were the only surface detection units available, if memory serves. IJN, etc., units were reluctant to use the sets as they were concerned about the enemy's ability to use the signal to successfully triangulate their positions.

Actually, Type 22s were put on some DDs as early as March, 1942.

Only Akizukis got the Type 21, I think. The Real IJN mod I did (not released stand-alone yet) is included in RSRDC and has the 3d models of the radars installed on all the ships at the appropriate times (so you can look at a DD through the scope and see if it has a type 13 array, or a rotating bedspring Type 21, etc )