A pretty unlucky military event was when one of the most advanced U-boats, capable of taking down British and American war ships, was sunk because of a poo.

In World War Two, a German navy submarine named the U-1206 departed from the port city of Kristiansand, in Nazi-occupied Norway, and began its first combat patrol. Its job was to sink and destroy American and British trade ships.
This U-1206, unlike former submarines, had a new and “improved” toilet which allowed the U-1206 to stay deep underwater while people could go to the toilet and flush it without going to the surface, which was not possible before, as in other submarines, you had to go up to the surface whenever you wanted to flush the toilet which was a big problem because Allied ships could see you.

Advanced and new as it was, the toilet was extremely complicated. First, it directed human waste through a series of chambers to a pressurized airlock. The contraption then blasted it into the sea with compressed air, sort of like a poop torpedo. The toilets also needed a specialist on each submarine who received training on proper toilet operating procedures. There was an exact order of opening and closing valves to ensure the system flowed in the correct direction.
One day the specialist on the U-1206 decided it was a bit boring waiting to flush a toilet every couple of hours, so he took a walk around the submarine. But unfortunately he went for too long, and the captain, Karl-Adolf Schlitt, went to the toilet and decided to flush the toilet himself.

But Schlitt was not properly trained as a toilet specialist. After calling a random engineer to help, the engineer turned a wrong valve and accidentally unleashed a torrent of sewage and seawater back into the sub.
From there on, everything escalated quickly. The unpleasant liquid filled the toilet compartment and began to stream down onto the submarine’s giant internal batteries, located directly beneath the bathroom, which reacted chemically and began producing a toxic chlorine gas.
As the poisonous gas filled the submarine, Captain Schlitt — choking literally on a weird sewage chlorine gas — ordered the boat to the surface. The crew blew the ballast tanks and fired their torpedoes in an effort to improve the flooded vessel’s buoyancy.
Unfortunately for Schlitt and its crew, it got even worse. British planes on patrol saw the ship surfacing and attacked it, killing three men, and, because of that, it started to sink.
Somehow, the rest of the crew survived and floated all the way to the Scottish coast in rubber dinghies, where they were captured and taken to a POW camp for the rest of the war.
Schlitt survived the war and died in 2009. His submarine, on the other hand, rests on the bottom of the North Sea to this day.
And that, ladies and gentlemen, was one of the most unfortunate events in military history ever.
In the 1200s, the Mongols dominated the eastern hemisphere.

In 1266, Kublai Khan, the emperor of Mongolia then, sent a letter to Japan demanding tribute. Japan declined.
Not smart.
In 1274, Kublai Khan sent 600 ships and 40,000 soldiers to invade the Japanese.
The Mongols were met with Japanese resistance at Hakata Bay, but the Japanese were defeated and forced to retreat.
When nightfall came, the Mongols halted their advance and sailed farther out to sea due to the risk of being marooned by strong winds and approaching storms.

And, they sailed right into a typhoon.
Not letting this stop them, the Mongols sent another invasion in 1281.
This time they had two fleets of ships, a smaller one departing from Korea, and a larger one departing off China.
The Korean fleet arrived first and began the attack; however, Japan was prepared and neither side was making progress.
Then, the larger fleet from China arrived, and the Japanese were pretty much sitting ducks.

And then another typhoon hit.
The Mongols never conquered Japan.
By dumb luck, the Japanese were spared.
Japan had the unluckiest five minutes suffered by any country at war between 10:25AM – 10:30AM, June 4th, 1942, at the Battle of Midway.
The background is that, after Pearl Harbor, Japan had gone on a tear in East Asia and the Pacific, winning a series of stunning victories. Her core naval doctrine however was predicated on winning a battle of annihilation, like the Battle of Tsushima , after which she would negotiate a peace on favorable terms.
So far, she hadn’t been able to bring that about, but she figured an invasion and occupation of Midway Island might entice what’s left of the the US Navy in the Pacific into showing up for such a climactic fight.
The Japanese calculated that the US Navy only had 1 or 2 aircraft carriers left in the Pacific, and so launched their operation against Midway with 4 fleet carriers.
The Americans however had cracked the Japanese naval code and knew that an attack on Midway was coming. More importantly, the US Navy had more carriers in the theater than expected – one carrier had been transferred from the Atlantic to the Pacific, and another one that had been damaged in an earlier battle and was expected to take months to fix, was back in operations after only 48 hours of hurried repairs, giving the Americans 3 carriers instead of 1 or 2.
The Japanese, unaware of the presence of US carriers near Midway, launched a carrier attack against installations on the island early in the morning of June 4th. They inflicted significant damage, but it was decided that a second strike would nonetheless be necessary.
So the Japanese aircraft that had struck the island were recovered and readied for round 2. However, in the midst of readying that second strike against the island, the Japanese discovered that there were US aircraft carriers in the area.
Destroying aircraft carriers was more important than hitting Midway – the island wasn’t going anywhere – so orders were given to switch the bombs on the Japanese aircraft, intended for ground targets, to bombs and torpedoes suitable for attacking ships.
While that was going on, the US carriers had already launched their own aircraft against the Japanese fleet. Devastator torpedo bombers – slow aircraft that had to fly low, steady, and straight, in order to launch their torpedoes – got there first.

41 Devestators attacked the Japanese carriers without fighter escort. 35 of the 41 were shot down. They didn’t score a single hit.
In the meantime, a flight of US Dauntless dive bombers

was pretty much lost, trying to find the Japanese fleet. They had reached the point beyond which they wouldn’t have enough fuel to make it back to their own carriers, but their commander decided to keep going, and soon saw a lone Japanese destroyer below. He used its wake as an arrow and followed that direction. It led him directly to the Japanese fleet.

And a Japanese fleet caught with its pants down. The Japanese carriers were rearming and refueling, so their decks were full of bombs and torpedoes and gasoline hoses. Not only that, but there was no fighter cover – the Japanese fighters had gone down to intercept and destroy the American torpedo bombers which attacked at wave top level.
They hadn’t yet regained altitude when the US dive bombers showed up and dove down from high above. Within 5 minutes, 3 of the 4 Japanese aircraft carriers were on fire. The fourth Japanese carrier was sunk later that day.
What made it extra devastating for the Japanese, even more important than the loss of the carriers, was the loss of trained pilots and aircrew. Japanese naval aviators were the best in the world at the time – almost like the Navy SEALs of pilots. A cream of the crop. But a cream that took a very long time to train, and the Japanese didn’t have a pipeline system that could train replacements as quickly as the US Navy could pump out naval aviators.
So from that point on not only would US Naval aviation overwhelm the Japanese with quantity, but with the catastrophic Japanese pilot losses at Midway and the inability to replace them with enough similarly well trained pilots, with quality as well.
