For those playing GWX with the TKSS18 German U-Boat Compilation part 1 & 2, plus the German U-Boats Compilation 2 (only VIIB & VIIC models by WISE), be aware that the visual values of their sensor.dat DOES NOT correspond at all with GWX values.
You’ll have to open the last sensor.dat activated in your mod list, and give stock GWX values

Otherwise your watch crew will be blind and detect ships only very close.