Naval architecture in the Sixteenth Century consisted of a lot of "TLAR" engineering ("That Looks About Right") and "Has it sunk yet? No? Put more cannons on it then."
On this date in 1545, during an engagement with the Frog navy, the 91-gun Mary Rose, pride of the English fleet, took a sharp turn, heeled in the breeze, and started shipping water through her lowest gunports. She capsized quickly and sank like a rock, with the anti-boarding netting draped over her ensuring that most of the soldiers and sailors crowding her fighting decks went down with her. Not that the soldiers would have been doing much swimming in armor, anyway, even the few that could swim.