What the heck just happened?
I was heading for Fremantle after a short, but fructuous patrol (Something like 79K tonnes; 20 or so ships, including a whole whack of sampans

Got lucky, or the DD's were sleeping.)
Suddenly, off the coast of Australia, between Fremantle and that base with no name, my submarine is destroyed. I was running at full TC, ahead standard, the usual... Then all of a sudden, BAM!
The short 3D pan out was kind of unclear, there might have been some sort of shoal there, but I was pretty far offshore (I do know how to plot a course

) and I never got a shallow water message or anything of the like.
Any minefields in the area? Or is this a bug?
The most annoying thing is that I hadn't saved since leaving base. Awesome.