The ESM sensor on AI subs has also been fixed for the new version.
Since in the default version only the periscope (visual sensor) on the AI platform could detect contacts when the sub is at periscope depth.
Now, the ESM sensor will also operate at periscope depth and detect radar emissions.
Simply put - the ESM sensor at AI Sub, got its own working telescopic mast.
However, I'm more and more concerned about realism versus playability.