The moon shines down on a stretch of beach along a remote Japanese island. The waters
here run deep just a few feet from the beach, which makes it a perfect training ground for
the pilots who will soon be in charge of Japan's latest, devastating weapon- the kamikaze torpedo.
By mid 1944 the war in the Pacific was turning for Japan. Humiliating and disastrous defeats across
the South Pacific had seen the Japanese fleet utterly decimated. While it still had a numerous
surface navy, almost all of its carriers had either been destroyed or sunk. The news underwater
wasn't much better- Japanese submarines were being overwhelmed by mass-produced American destroyers-
every time one was sunk, it seemed like two sprung up in its place weeks later.
Now the remaining submarine fleet was ordered to stay close to the relative safety of the
innermost Japanese shipping lanes, which were themselves being decimated by American subs.
The Japanese navy, which had briefly ruled the Pacific after the devastating surprise attack
of Pearl Harbor, was increasingly becoming an endangered species.
The Japanese doctrine of decisive battle has failed them to date, and only now with its fleets
on the ropes, is the navy realizing this fact. For years the IJN has sought to decimate the US Navy
in one final, decisive engagement reminiscent of past naval battles of the 19th century. However,
this is antiquated doctrine by World War II, and the US has bought itself the time to rearm and
re-equip itself by engaging a running battle with the IJN, striking quickly and decisively
before disengaging. By the start of 1944, the US is no longer disengaging, it is holding its ground
and fighting- and without her carrier fleet the Japanese navy can no longer win a decisive battle.
Desperate times call for desperate measures- a weapon that can reliably sink American ships is
desperately needed. But war materials are running short due to incessant attacks on
shipping by American subs, and some supply lines are no longer viable due to Allied blockades.
Necessity though is the mother of invention,
and two Japanese naval engineers come up with a desperate, but decidedly powerful weapon.
The standard torpedo of the age is unguided, and instead are pre-programmed to run at a set depth
and course. Initially torpedoes would skim the surface or run just a few feet below it,
striking an enemy vessel dead on. However, with ever improving armor for big battleships and
cruisers, it was feared that torpedoes would no longer be viable options on these targets-
thus torpedoes were designed to run under the hull of a ship.
Once approaching the underside of the hull, the torpedo's magnetic exploder would detonate,
setting off the primary explosive payload. The massive force of the explosion would strike
the ship where it was weakest- at her keel. Structural damage would thus doom the ship,
or at least heavily damage it and render it mission ineffective.
To improve accuracy against moving targets, and to allow submarines to fire at targets without
needing to fully face them head-on, torpedoes were developed that could be preprogrammed with
a target's course, distance, and speed. Then, the torpedo could be fired, and the weapon
would execute a wide swing towards the estimated intersection point, exploding upon arrival if a
ship was there or simply continuing on until it ran out of fuel and sank to the depths.
While improvements had been made, torpedoes were still wildly inaccurate, and a better solution
had to be found to make the most use of Japan's dwindling war materials. Today, with the moon
shining down on a formation of twelve young Japanese men, that solution has been found.
The assembled men's ages vary from eighteen to the early twenties. Some are even younger, having
falsified their ages in order to enlist. These are the last of Japans' available military manpower-
most of its veterans have either been wounded too severely to continue serving or lost in battle.
Those that survive are far too valuable for this secret mission, but the young men are
mostly fresh recruits. Young, willing, dedicated body and mind to the Emperor,
and completely expendable. The Emperor protects.
On command, the first young man rushes to the breaking surf where a strange craft awaits him.
It resembles a torpedo, with a length of about 30 feet (9 meters), but has a bubble canopy
and a canvas seat inside of it. The makeshift cockpit has very rudimentary controls,
and no seat belts or any other form of basic safety equipment- there is no need for it.
The young man jumps into the cockpit and closes the canopy, sealing him inside.
The rest of the men help push the manned torpedo into the water,
and soon the torpedo has pulled free of the sand. The pilot activates the torpedo's
battery powered propeller, and the entire contraption lurches forward and out to sea.
This is just a training exercise, and each man will take his place inside
one of several training torpedoes. Their goal is to maneuver the torpedo to make a
run underneath a small practice vessel sitting at anchor several hundred feet
from the shore. Today the torpedoes contain no explosive charges, but soon they will.
The torpedo slips beneath the waves like a small submersible,
running just a few feet under the water. The controls are rudimentary though,
and the torpedo can be a little difficult to steer properly for the inexperienced pilot. That's fine,
in combat the pilot will need to make only small adjustments. Even a novice skill level
is suitable for what will be the first, and last mission of each pilot's life.
Eventually the young man steers the torpedo true, and as he nears the practice vessel he
presses down on a foot pedal meant to force the torpedo to submerge. The torpedo however
does not respond. These machines have been quickly assembled, the engineering is rough,
as is expected of a weapon meant to be used only once. As the torpedo nears the simulated
enemy vessel, the pilot desperately kicks down on his pedals- but the torpedo does not respond.
A second later, there's a sickening crunch as the torpedo slams straight into the side of the
ship. The entire front nose section, where the explosives would be on a real weapon,
collapses in on itself. The pilot, with no safety restraints of any kind, is hurled forward and into
the controls with the violence of a 45 mph (72 kmh) wreck. His face is fractured in multiple
places, and his neck broken on impact. The shattered canopy quickly fills with water,
and men aboard the ship frantically begin rescue efforts- only to be stopped by their captain.
There is no point, the young man has given his life for the glory of the emperor.
Back on the beach the instructors give a solemn nod before barking out a command,
ordering the next fresh recruit into one of the remaining training torpedoes.
Life in Imperial Japan is cheap, and easily expended for the Emperor.
Those that survive today's training will soon find themselves earning that glory for themselves.
Several weeks later, four of the recruits find themselves aboard a Japanese submarine. Two other
submarines make for a small wolf-pack, and the Japanese are stalking a convoy of American ships.
Overhead, a Japanese recon plane has spotted the convoy and maintains visual contact
while staying out of range of the escort destroyer's guns,
relaying course data to the submarines below the waves.
One of the subs speeds forward to drop a dummy mine in the path of the convoy.
The lead ship shortly after spots the mine and the entire convoy changes course to avoid it,
with the USS Underhill moving into position to sink it. After strafing it with its 20 millimeter
guns and rifle fire, the Americans realize that the mine is a dummy and a diversion.
Immediately the men of the Underhill begin hunting for enemy submarines. Prior to the
mine being deployed, the sonar operator had made a sonar contact signaling an enemy sub-
but in the efforts to neutralize the mine the contact had been lost. Now contact has been
reestablished, and the Underhill moves straight towards what turns out to be a surfaced Japanese
submarine. The destroyer's engines are given full power as the ship moves to ram the submarine,
a common tactic that causes little damage to a destroyer but will split a submarine in half.
The Japanese submarine submerges at the last moment, but the Captain
of the Underhill gives the order to drop depth charges. After dropping 13 charges,
oil and debris float to the surface- the Japanese sub has been neutralized.
A second sub however has moved to avenge the lost boat.
Aboard the surviving Japanese submarine, an order is given and the two young men
who had been training on a sunny beach together just a few weeks ago
spring into action. They crawl down a long metal tube which connects to the kamikaze torpedo-
named Kaiten. The torpedo is bolted onto the deck of the submarine,
and once the pilot crawls into the cockpit, the attaching metal tube is disengaged.
These combat-ready models lack the bubble canopy of some of the training models,
and so each pilot sits in the dark. Small slits allow them to see somewhat out of the cockpit,
but the waters are too deep and murky to see much of anything. A periscope several feet high
can be extended, and will be the primary way of guiding the torpedo to its target.
Suddenly with clang, the two torpedoes are disengaged from the submarine.
The mission is on, and the objective simple: find and destroy the American vessel.
The submarines quickly rush to the surface thanks to their buoyancy, and the electric engines kick
on lurching the suicide weapons forward. The makeshift cockpit groans and creaks with the
water pressure, and moisture leaks in from a dozen places. The pilots have to be careful
to try and wipe away moisture from the rudimentary instrument panel and controls,
fearing a short that would make the kaiten completely uncontrollable.
Soon, the two torpedoes are at the surface, and the pilots use their periscopes to break
the cover of the waves above them and take in the surrounding view. Up ahead of them is the American
destroyer that's sunk one of their submarines, a perfect target that seems completely unaware of
their presence. Lining up a new course, each torpedo slips a few feet beneath the waves
and turns towards the American ship, powering the engine to full speed.
Aboard the Underhill, the sonar operator picks up the distinct sound of underwater propellers- too
faint to be a submarine but too loud to be regular torpedoes. Confused, he relays this information to
the Captain, who orders a change of course and a fresh round of depth charges. Deployed from racks
on either side of the hull, depth charges tumble down into the ocean, exploding at varying depths
below the destroyer. The charges don't need to be accurate, they only need to be close enough
for the pressure wave from each explosion to collapse the hull of an enemy submarine.
The Kaitens are running at full speed towards the Underhill,
and each pilot surfaces briefly to get a new fix on the American ship before submerging again.
If they're spotted early the ship's guns would easily blow them to pieces, so the
men must run with only occasional glimpses at periscope depth to ensure they remain on course.
Nearing the ship, both Kaitens submerge.
The Underhill continues to record sonar contacts,
and the depth charge barrage intensifies. There is some confusion, but little fear-
the enemy submarine is now so close that it cannot bring its torpedoes to bear.
A fresh barrange of depth charges sink into the ocean, followed by the dull roar of explosions.
Two dozen feet below the ship, the force of the explosions propels the Kaitens
upwards unexpectedly. One of the suicide torpedoes suffers fatal structural damage,
and after breaking the surface, begins to sink almost immediately. The second hower
breaks the surface on the opposite side of the ship, but remains largely operable.
The men on the deck of the Underhill can't believe what they're seeing,
two enemy manned submersibles on either side of the ship. Both are so close though that
they can't bring any of the destroyer's guns to bear, so the captain makes a fateful decision.
The Kaiten can out manuever the big ship at this range, so the Underhill must take
advantage of the situation before the pilot can recover control of his suicide vessel.
The destroyer turns hard to port at flank speed, intending to ram the Kaiten and sink it.
As the ship strikes the manned torpedo, the move proves to be a miscalculation.
The pilot sets off the torpedo's explosives, rocking the big destroyer.
The ship is broken in half by the massive explosion at its forward fire room,
with the bow being detached and floating away sticking straight up into the air. 112 of the crew
have died in the two resulting explosions, and the Underhill is a total loss. What remains floating
of her will be sunk by friendly fire, with the surviving crew transferred to other ships.
It is a victory for the IJN and for the Emperor.
But it's a rather pyrrhic victory, and the Kaiten suicide torpedo program will go on
to be largely ineffective, costing the Japanese more in materials and manpower than the Americans
they were meant to sink. In total, the Kaiten program would kill about 187 allied servicemen,
with only two major kills to its credit- the Underhill and the USS Mississinewa.
Meanwhile, the program would cost the Japanese hundreds of lives in failed deployments,
training deaths, and losses incurred by the sinking of submarines equipped with the weapons.
Instead of helping level the playing field for the Japanese,
the Kaiten suicide torpedo program would help ensure its total defeat.
Now go check out Why Japanese Soldiers Became Texans, or click this other video instead!