Grey Sunk Icon
 

I'm familiar with the red sunk ship icon, which is a good thing. I'm also familiar with the green sunk ship icon, which normally means you've sunk a neutral. What am I to understand by a grey sunk icon?

I broadsided a ship, noted the time of impact, and turned to its heading to prepare to follow it for a few hours to see whether it was going to sink. Surprisingly it sank quite quickly, but left a grey icon.

Probably means it was sunk by weather or planes or surface ships.

The Grey icon means the ship sank from something that wasn't you. Whether it be weather, running aground or even an enemy vessel.

It also can mean a ship that sunk that wasn't visibly witnessed by you.

And sometimes they just sink beneath the surface without any mark whatsoever.

I smacked an ore carrier the other and she went down... but no credit or map mark. Granted, I was 7000 off at the time dealing with someone else, but I was keeping an eye on her.

It's happened a more than a few times over the years, but I just write it off to stupid, careless KM bureaucrats.