I remember someone on the subsim.com boards saying that SV air radar and SS surface radar started replacing SD and SJ, respectively, in 1945. I thought that we had something from the 50's or 60's, but it's nice to know that it's almost original equipment. It's funny how some boats have been modified 100 times and others have gone almost untouched. Batfish has had a lot of external mods, but the interior was practically left alone. I'm glad that the Guppy mods got too expensive for the Navy. They unwittingly left us some history to preserve. On the other hand, the poor slobs that went to sea in Batfish in the late 50's/early 60's were probably wondering when they'd get a better assignment and why they were stuck still working with old vacuum tube electronics.