Early PT Boat. Notice the two torpedoes on this side and the twin 2 50-calibre machine guns.

You might think torpedos have been around a long time. As far back as 1275, one inventor was thinking about “an egg which moves itself and burns.”

But the torpedo as we know it didn’t really appear until the late 1800s. Earlier torpedoes were more like underwater mines that exploded when touched. But a British engineer named Robert Whitehead figured out how to propel those explosive mines through the water, creating the modern torpedo.

Unfortunately, Whitehead’s early torpedos were unreliable and slow. They couldn’t be counted on to hit a target.

Whitehead kept working on his invention. By 1870 he’d figured out how to use compressed air and an explosive charge to fire the torpedo, pushing it 1000 yards through the water. Still, these torpedos weren’t fast and sometimes they didn’t stay underwater.

Whitehead refused to quit. By 1881, his torpedo design was so good that ten countries ordered it for their navies. Around the world, other inventors tinkered with the invention, improving its speed and accuracy, and by 1900, the torpedo was considered a worthy weapon for warfare. It was sinking ships.

Now the question was, What king of ship for firing the torpedos? In the early 1900s, huge battleships ruled the seas but they were expensive to build. For the same cost as one battleship, a country could build dozens of smaller torpedo boats that could do serious damage in battle.

But like the torpedo itself, the torpedo boat took awhile to perfect.

The first boats manufactured in the United States were called PT boats, for Patrol Torpedo. The early models were sold to other countries because America’s military didn’t think they were good enough. The navy wanted more massive destroyers.

Then, in the 1930s, America found new interests in the Philippine Islands, and these patrol boats seemed useful for coastal defenses. Several boat builders entered a competition and each patrol boat entry was numbered, from PT-1 through PT-19. The navy tested them all, but once again decided the PT wasn’t up to American military standards. But in 1941, the Electric Boat Company (Elco) designed the PT-20.

Seventy-seven feet long and weighing thirty-three tons, PT-20 carried four torpedoes, eight depth charges, and two twin-50-calibre machine guns. It also had three engines boosting the wooden vessel to speeds of 41 knots, or 47 miles per hour, since one knot is equal to 1.15 mph.

That same year, Japan bombed Pearl Harbor.

Suddenly the PT boat hit the Pacific Ocean.

The PT crews consisted of two officers and ten enlisted men. As WWII progressed, the PT boats started carrying smaller— but more powerful—torpedoes and sometimes radar. Quick-moving and deadly, the PT boats attacked cruisers, destroyers, submarines, and supply barges all the way from the South Pacific to the Mediterranean Sea, from the English channel to the Aleutian Islands of Alaska.

These “buccaneers of the sea” destroyed hundreds of barges in the Pacific Ocean loaded with Japanese troops and supplies.The PT boats also snuck into enemy harbors, conducted sabotage and raiding missions behind enemy lines, and rescued Allied crews whose air planes had gone down at sea.

All the while, the PT boats were fighting against massive coastal guns and ships that were 100 times their size—and they were winning. Because the PT boats were so fast and so hard to sink, squadrons started calling them "the mosquito fleet."

But the Japanese, after suffering many losses because of the PTs, called them “Devil Boats.”


PT 109 in the South Pacific

On a moonless night of August 2, 1943, Lieutenant John F. Kennedy and his crew about the PT-109 were trying to avoid detection by Japanese aircraft. So they were quietly idling on one engine, in the dark.

But sometime around 2:00 a.m., the crew realized that a Japanese destroyer was headed right their way. The crew had only about ten seconds to fire up the engines.

The destroyer hit them, slicing PT-109 in half. The collision killed two men and badly injured two others. The only thing keeping the boat afloat were its watertight compartments keeping in the forward hull. The rest of the boat was in flames.

The eleven survivors clung to the bow section as it drifted slowly south. But when the hull started taking on water, the men knew it would soon sink. Kennedy decided the crew’s best chance of survival was to swim to some nearby islands. But he knew all the large islands contained Japanese prison camps. Placing lanterns, shoes, and the men who couldn’t swim on a piece of wood that was the boat’s gun mount, Kennedy and his men swam for one of the smaller islands.

They swam for hours. An expert swimmer, Kennedy saved one enlisted man’s life by clenching a strap from the man’s life vest between his teeth, towing him more than three miles to shore.

The island where they landed was only 100 yards across--the size of a football field. It had no food or fresh water, and the crew needed to hide from passing Japanese barges. Kennedy swam another two-and-half miles in search of food and help. He then led his men to another island that had fresh water and coconut trees.

Kennedy and the ten surviving men lived on coconut milk and rainwater. Some island natives discovered them and offered shelter. Each night, Kennedy would send out signals, hoping to make contact with one of the American naval ships in the area.

Six days later, a patrol boat came to their rescue.

Later, Kennedy was awarded military honors for his courage and leadership under fire.

In 1960, he became the 35th president of the United States.



PT Boats in Action -Warships No. 34 by David Doyle

John F. Kennedy and PT-109 by Richard Tregaskis

ELCO 80 PT Boat -On Deck Color Series No. 5 by David Doyle

Higgins PT Boats On Deck by David Doyle


Here’s a YouTube video of the only operational PT boat still in existence.

Longer video on the history and use of the PT during WWII.


They Were Expendable

PT 109

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