Unstable ships


Stable.

One spoon of water.
A small amount of water on the bottom of the ship makes it unstable.

Instability of a huge ship
Costa Concordia, friday 13 januari 2012, Isola del Giglio.

Instability of roll-on roll-off ships
Herald of Free Enterprise, 6 march 1987, Zeebrugge.
MS Estonia, 28 september 1994, Baltic Sea.
The al-Salam Boccaccio '98, 3 february 2006, Red Sea.