First of all, 512x TC is a pinch high for being on the surface off the coast of Japan, especially during the daylight hours. Secondly, the H6 radar we enabled in v1.46 is too "strong" and has been turned down to be less "efficient" for the next release. The "Preview" is posted if you want to try it out. Thirdly, once you are spotted, they will keep after you, possibly flooding the area with planes. It is relatively easy to calculate how far a submarine can get in a given period of time. If it gets too "busy" with planes, the thing to do is to submerge, and change direction, and stay down for a while. Maybe wait until dark before surfacing again. Then ske-daddle back to where you want to be, but avoid being seen. If you get a radar contact coming your direction, check its trajectory and if it will come within say 7nm, crash dive and stay down 10-15 minutes dependent upon the planes trajectory across your path, then pop back up. Check-out Rockin Robbin's video for more pointers.
Kind of an important thing to remember about the game, is that somehow or other, the IJN can "home-in" on your radar signals, even before they technically had radar detectors, but alas, it is a game after all...
