On patrol somewhere off the Philippines late
one night in the middle of 1943, a Japanese destroyer slowly cruises through shallow coastal
waters. Her captain scans the horizon with his binoculars,
but the seas are pitch black. He's not worried about an American submarine
attack, the waters are too shallow here, and besides bristling with weapons as she is,
the destroyer is more than capable of defending herself if attacked either by sea or air. The big guns of the American battleships also
don't worry him, the Americans are still rebuilding their fleet after the devastation of Pearl
Harbor half a year ago. Even if by some miracle an American battleship
was in the vicinity, well, Japanese destroyers are formidable themselves, and he could always
call for air support from a nearby airfield- it would be a suicidal attack. Confident in his ship and his men both, the
Japanese Captain allows himself to relax for a moment, he even considers retiring to his
quarters and letting his second assume command for yet another uneventful night. Then, suddenly, the ship is rocked by an explosion
at her bow! Submarines? Impossible, the waters are too shallow! Scanning the seas he doesn't see the silhouette
of a large American ship against the moonlit waters either. Suddenly a second explosion strikes the destroyer
amidships, sending the bridge crew to the floor. As they pick themselves up they hear the approaching
roars of engines- aircraft?! Impossible, no chance American airplanes could
be so accurate in the dead of night! Yet the roar of engines grows, and soon there's
a third explosion and the ship lists. Scanning the dark with spotlights, Japanese
crewmen catch glimpses of something unbelievable- small, agile speed boats loaded with torpedo
tubes and machine guns are roaring by the big destroyer, reaching speeds of up to 45
mph (73 km/h)! The big destroyer turns her guns to defend
herself but the small boats are too fast and agile, and in minutes they've landed several
more direct hits. As the Japanese destroyer sinks, a small fleet
of 4 American PT boats roars off into the night, disappearing as suddenly as they had
arrived. The legendary PT boat of World War II had
its origins in the days before World War I, when military planners saw potential for a
small, high-speed ship that could deliver torpedoes and flee from combat before the
enemy could sink it. Despite several successful trials and some
interest from both the Americans and the British, the designs were scrapped in favor of big
gun battleships and cruisers- this was the age of the Dreadnought after all, and the
world firmly believed that naval power lay in big ships and even bigger guns. Yet as technology progressed and ever more
powerful engines were developed, small speed boats began setting incredible speed records
of up to 60 mph (96 kmh) on calm seas. Speed derbies featuring ever faster boats
had become very popular in America, and in the late 1930s military engineers began seeing
the potential once more for small, agile boats capable of launching deadly hit and run attacks. In 1938, with the probability of the US going
to war soon, the US Navy sponsored a design competition for a highly mobile attack boat,
reaching out to the designers of speed boats used in the popular derbies. The competition led to the construction of
eight prototype boats which would compete in two different classes. The first class of boat was for 54 foot (16
m) boats, and the second for larger, more heavily armed 70 foot (21 m) boats. Prizes for winning designs were awarded on
the 30thof March, 1939, and on June 8thof that year, contracts were awarded to the Fogal
Boat Yard of Miami, Florida, and the Fisher Boat Works of Detroit, Michigan. This led to the development of the first four
official PT Boats to be tested and refined by the US Navy. In March of 1941, a squadron of Navy PT boats
made a run from Key West to New York. The 70-footers as they were known were heavily
pounded by seas reaching 8 to 10 feet in height, and the boats were only able to travel at
moderate speeds well below their maximum. The crew suffered from extreme discomfort
and fatigue, and the boats each suffered several structural failures. The hulls were clearly deficient and the navy
ordered immediate overhauls to the basic design. Later that July, the Navy gathered together
nine boats of different designs and held an open-ocean trial to test each boat- the sailors
involved would reference the test as the Plywood Derby, so named for the light wood from which
most of the boats were made. The open ocean trial would run a course of
220 miles (350km) with each boat at full throttle, and each ship would carry either live ordinance
or copper ingots that would stand-in for actual weapons. Of the nine ships that partook, only six finished
the trial successfully, with the fastest ship clocking in at an average speed of 45.71 mph
(73.56 kmh). A second trial later on in August would see
the ships running a 213 mile (343 km) course through much heavier seas, with waves reaching
heights of 16 feet (4.9 m). Six designs took part in the trial and all
but one completed successfully. Even with rough seas, the fastest boat reached
an average speed of 31.6 mph (50.9 kmh). The Bureau of Ships quickly issued a report
encouraging the immediate construction of several PT boat designs, all to be armed with
dual torpedo tubes, machine guns, and depth charges. Each boat varied in crew size, but typically
ran from three officers and 14 enlisted men up to as many as 17, depending on the total
weapons loadout of each ship. The hulls were made of two sheets of mahogany
planking with a glue-impregnated cloth layer in between the inner and outer planks. At a time when ships of war featured heavy
belts of steel armor that were anywhere from several inches to a foot or more thick in
places, the wood panel construction of a PT boat must have seemed suicidal. Yet the lightweight wooden hulls allowed the
boats to reach incredible speeds even when fully loaded with weapons, and a PT boat that
had just emptied its torpedo tubes and spent its depth charges could speed away at speeds
up to 60 mph (96 kmh). Plus the wooden hulls were incredibly easy
to repair, and the ships were capable of sustaining catastrophic damage and surviving. When future US President John F. Kennedy's
PT boat was ran over by a Japanese destroyer and cut in half, the two halves of the ship
managed to remain afloat for a full 12 hours. PT-323 when cut in half by a kamikaze aircraft
on december 10th, 1944 also remained afloat for hours. PT-308 collided with another PT boat by accident
during a night mission and had her stern completely sheared off, yet managed to return to base
for repairs. Easy to repair and extremely survivable after
receiving battle damage, the wooden hulls of PT boats also afforded them a great degree
of protection form metal-detecting sea mines, and in some cases even from enemy torpedoes. On the 5thof November, 1943, a torpedo fired
at PT-167 shot straight through the hull of the boat without detonating, and the boat
remained in action until being repaired the next day. Nicknamed the 'mosquito fleet' or 'devil boats'
by the Japanese, PT boats may have been small but they packed a formidable punch. Each boat carried a primary anti-ship armament
of anywhere from two to four Mark 8 torpedoes, packed with 466 pounds (211 kg) of TNT. The torpedos had a range of 16,000 yards and
could zip through the water as fast as a PT boat itself, reaching speeds of up to 41 mph
(67 kmh). However the explosive charges that fired them
from their containers became a dead-giveaway when conducting nighttime attacks, and thus
they were eventually replaced in 1943 by lighter, more powerful Mark 13 torpedos featuring a
600 pound Torpex-filled warhead. Torpex was a new explosive which featured
50% greater explosive energy by mass over traditional TNT, seriously upgrading the firepower
of America's PT boats. The new torpedos were also fired from roll-off
launch racks, eliminating the tell-tale explosive burst that would give PT boats away at night. Each PT boat was also equipped with at least
two twin .50 cal machine guns which could be used an anti-aircraft weapons. On the stern would also be mounted a 20mm
Oerlikon cannon which was capable of punching through light ship armor. Forward of the chart house would be two .30
caliber Lewis machine guns on pedestal mounts, as well as one or two .30 caliber Browning
machine guns on the forward torpedo racks. The PT boat literally bristled with armament,
yet a year into the war the US decided that PT boats definitely needed more guns and started
installing additional 20mm cannons amidships and on the forward deck. Yet for some PT boat captains and enterprising
engineers with lots of time on their hands, even this wasn't enough. PT boats became famous for the high degree
of customized and 'home-built' retrofits, with engineers at forward bases in the Pacific
mounting everything onto PT boats from 37mm aircraft cannons to rocket launchers and even
mortars. After proving how successful the additional
firepower was, the Navy immediately adopted the modifications into the official design. Still, custom modification pervaded the PT
boat fleet, and one of the most famous was future US President John F. Kennedy's PT-109,
which featured a single-shot Army M3 37mm anti-tank gun that the crew had commandeered. The enterprising sailors and mechanics removed
the wheels and lashed it to 2x8 timbers before affixing the cannon to the bow. The M3 anti-tank gun proved devastatingly
effective against ships, despite being made to take out enemy tanks, but the single-shot
action limited its usefulness. Enterprising PT Boats crew found the answer
to their problem by cannibalizing the Oldsmobile M4 aircraft automatic cannons from crashed
P-39 Airacobra fighter planes. Once more demonstrating the effectiveness
of in-the-field ingenious customizations, the auto cannon was approved as part of the
factory design. Originally conceived as anti-ship weapons,
PT boats saw their roles vary dramatically as the war in the Pacific raged on. Some boats were converted to gunboats featuring
nothing but heavy machine guns which would aid landing US troops, or in the rescue of
downed pilots. Others would provide close-in fire support
with mortars for troops near the beaches, delivering more accurate fire than the big
guns of battleships and destroyers sitting a half dozen or more miles away. Yet the primary role of the PT boat was always
to harass and interdict Japanese shipping, and to do their job effectively they would
operate primarily at night. While at first only a few PT boats were fitted
with radar, eventually the use of radar spread across the PT fleet, which dramatically improved
the success of nighttime raids on Japanese ships. During the Solomon Islands campaign, PT boats
waged a deadly campaign against Japan's resupply efforts, dubbed “The Tokyo Express”. Operating in groups of 6-8, the boats would
lie in wait for Japanese ships, loitering silently just out of torpedo range. Once a target appeared, the boats would roar
to life and pounce on the unsuspecting enemy ship, loosing a deadly volley of torpedoes. Though their primary targets were Japanese
shipping barges which proved difficult to sink by submarines due to their low-draught
hull design, the PT boats regularly took on much more heavily armed opponents, even battleships. During the campaign Japanese captains were
cautious about operating their big capital ships in any waters known to be prowled by
the deadly American speed demons. Yet the most effective use of PT boats was
as “barge busters”. After losing heavy numbers of resupply barge
ships to Allied naval power, both the Germans in the Mediterranean and the Japanese in the
Pacific began operating their barges at night in very shallow waters. This would make it impossible for Allied destroyers
to follow them due to the risk of running aground, and allowed the barges to be protected
by shore-based firepower. Yet the shallow waters were no problem for
the American PT boats, which would zip in at daredevil speeds and deliver deadly torpedoes
while strafing the barges with cannon and machine gun fire. By the time shore-based firepower could respond,
the Americans would be long gone, leaving nothing but a sinking wreck in their wake. The use of PT boats in the Pacific was directly
credited as the reason why Japanese soldiers suffered severe food, ammunition, and personnel
resupply problems. One captured Japanese soldier's diary described
his fear of American PT boats, describing them as “the monster that roars, flaps its
wings, and shoots torpedoes in all directions”. America's first great naval commander, John
Paul Jones, once said, “I wish to have no connection with any ship that does not sail
fast; for I intend to go in harm's way.”, and we are sure that he would have been mightily
pleased with the legendary speed demons of World War II. Fast, agile, and packing a deadly punch, PT
boats were the knife-fighters of the Pacific, darting into extremely close ranges to deliver
crippling blows against enemy ships that ranged from supply barges up to destroyers and battleships. These were extraordinary weapons, manned by
extraordinary men who knew the only thing standing between them and death was one thing:
speed. Thought this video was interesting? Check out our other video, 50 Insane Submarine
Facts That WIll Shock You. See you next time!
