Carter Roy

So they steered the Lusitania closer to the coastal Irish cliffs.

a region where submarines tended to hide.

But typically, ships like the Lusitania could outrun U-boats.

Their top underwater speed was about nine knots compared to the Lusitania's 21 knots.

So passing slowly through an area that might have a U-boat was deemed safer than completely stopping.

And it might have been, had the weather been on their side.

In a worst case scenario, the sun came out.

Ireland is infamously foggy and rainy, but on this day, the sky cleared.

If you've ever been to Ireland on a sunny day, it's transcendental.

The hills turn a vibrant green like nowhere else, and the sun sparkles over the turquoise water.

On the Lusitania, passengers gathered on the outdoor decks to play shuffleboard and jump rope.

On the Irish coast, people picnicked watching the ship pass by.

Even though Lusitania was about 11 miles away, the visibility was so good, Irish locals could easily see it without binoculars.

And so could the submarine periscope.

Underwater in U-boat 20, Captain Walter Schwiger couldn't believe his luck.

He'd already sunk three ships in the past two weeks, and here was a fourth.

Plus, he still had torpedoes left.

and the Lusitania was the only boat in the area.

Captain Schwiger had no qualms about the American flags or possibly harming civilians on board.

He was dedicated to clearing international waters for German shipping, so much needed food and supplies could reach his homeland.