The periscope breaks the surface just long enough for one sweep.
Commander Samuel De grips the handles tighter, his knuckles white.
It’s June 6th, 1944, and through the magnified lens, he sees something that makes his blood run cold.
Destroyers, three of them Japanese, charging directly at USS Harter’s position off Tawi Tawi in the southern Philippines.
Range 1,200 yards and closing fast.
De calls out.
His executive officer, Frank Lynch, stares at him, waiting for the order every submariner knows by heart.
Dive deep.
Run silent.
Pray they pass overhead without detecting you.
But De doesn’t give that order.
Instead, he does something the Navy’s submarine school explicitly forbids.
Something his instructors called suicidal and tactically insane.
He aims his submarine’s bow directly at the lead destroyer and prepares to fire torpedoes straight down its throat.
Captain, they’re right on top of us.
Lynch’s voice cracks with barely controlled panic.
In the cramped control room, 79 men hold their breath.
The destroyer screws thunder above them like an approaching freight train.
Any second now, depth charges will rain down and crush their hull like a tin can.
What none of them know, what no one in the Allied command knows, is that USS Harter has stumbled onto the most closely guarded secret in the Japanese Imperial Navy.
Hidden in the sheltered waters of Tawitawi Anchorage just 6 miles away sits the entire Japanese mobile fleet, battleships Yamato and Mousashi, five aircraft carriers, 13 cruisers, and dozens of destroyers.
It’s the largest concentration of Japanese naval power assembled since the Battle of Midway.
And the only thing standing between this discovery and Oblivion is a 311 ft Gatetoclass submarine with a broken hydraulic system, dwindling oxygen reserves, and a commander who refuses to follow the rules.
By June 1944, American submarines in the Pacific are fighting with one hand tied behind their backs.
Torpedo failure rates hover near 50%.
Standard doctrine demands caution.
Attack from long range.
Avoid escorts.
Never under any circumstances engage a destroyer head on.
In 2 and 1/2 years of war, this conservative approach has cost the submarine force dearly.
52 American subs have been lost.
Thousands of men rest on eternal patrol beneath the Pacific.
What De doesn’t know is that the next four days will change submarine warfare forever and force the Japanese Navy to abandon their hidden base, disrupting their entire battle plan for the Pacific.
The destroyer is 900 yd away now, 800 700.
Fire tubes 1, two, and three, De says calmly.
11 months earlier, October 1943, US Pacific submarine commanders gather in Pearl Harbor for an emergency conference.
The mood is grim.
Admiral Charles Lockwood stands before a map covered in red X’s marking sunken American subs.
Gentlemen, we have a crisis.
Lockwood begins.
Our torpedo failure rate is unacceptable.
50% of Mark1 14 torpedoes either run too deep, fail to detonate, or explode prematurely.
Worse, our submarines are achieving only a fraction of expected kills against Japanese shipping.
The statistics are damning.
In the first 22 months of war, American subs have sunk just 725 Japanese merchant vessels, far below projections.
The Mark1 14 torpedo rushed into production without adequate testing has four critical flaws.
Faulty depth control, a magnetic exploder that detonates prematurely, a contact exploder that crumples on impact, and an overall design that makes it run 10 ft deeper than set.
But the torpedo isn’t the only problem.
Submarine doctrine itself is failing.
Captain John Cromwell, who commanded submarine operations in the Atlantic, presents the conventional wisdom.
Submarines must avoid surface escorts at all costs.
A destroyer can outrun us, outturn us, and kill us with a single depth charge pattern.
Our job is to slip past the escorts and strike the merchant vessels.
Hit from long range, 5,000 yards minimum, then dive deep and evade.
The admirals nod.
It’s logical.
It’s safe.
It’s costing them the war.
In the audience, a littleknown submarine commander shifts uncomfortably.
Samuel David Dey, 36, from Dallas, Texas, graduated from the Naval Academy in 1930.
Not at the top of his class, not particularly distinguished.
He spent most of the 1930s on battleships and destroyers.
He’s only been commanding submarines since December 1942 when he took USS Harter fresh from the shipyard.
De has no advanced tactical training, no combat innovations to his name, no reason to believe he’ll be anything other than competent.
After the meeting, he approaches Lockwood with a radical idea.
Admiral, what if we’re thinking about this backwards? Lockwood frowns.
Explain.
We’re treating destroyers like threats to avoid, but destroyers are themselves high value targets.
Every destroyer we sink is one less escort protecting their carriers and battleships.
And if we could develop tactics to reliably kill destroyers, Deils off seeing the skepticism on Lockwood’s face.
Commander, our analysis shows that head-on attacks, so-called down the throat shots, have a success rate below 10%.
The torpedo spread is too narrow, the target profile too small, and if you miss, the destroyer is right on top of you with no time to escape.
Permission to try anyway, sir.
Lockwood studies him.
Why would you risk your boat and crew on a tactic with a 90% failure rate? Because sir, if we don’t change something, we’re going to keep losing boats at the current rate.
52 submarines gone.
That’s over 4,000 men.
I’d rather die trying something new than die doing the same thing that’s not working.
The room falls silent.
Every officer present knows someone who didn’t come back.
USS Wahoo, USS Grunion, USS Argonaut, USS Amberjack.
The list grows longer each month.
Expert consensus is clear.
Avoid destroyers.
Stick to merchant vessels.
Minimize risk.
The Imperial Japanese Navy has 391 submarines and surface combatants.
The American submarine force has less than 150 operational boats in the Pacific.
They cannot afford to lose even one more in a reckless attack.
Lockwood makes his decision.
Request denied, commander.
Follow standard doctrine.
Dismissed.
As De walks out, he passes a bulletin board posting new orders.
USS Harter assigned to patrol the approaches to Tawi Tawi, a remote anchorage in the southern Philippines.
Intelligence suggests the Japanese may be using it as a staging area.
The stakes have never been higher.
Allied forces are preparing to invade the Marana Islands.
Success depends on the Pacific Fleet locating and destroying the Japanese mobile fleet before it can interfere.
So far, Japanese naval movements remain a mystery.
No one suspects that the biggest naval battle of the Pacific War is about to hinge on what one by the book submarine commander discovers and what he decides to do about it.
USS Harter departs Fremantle, Australia on June 5th, 1944 for her fifth war patrol.
It’s supposed to be a routine surveillance mission.
Patrol the waters around Tawitawi, report enemy movements, avoid engagement.
But something has changed in Sam Dy.
During Harter’s fourth patrol, he watched from his periscope as a Japanese freighter exploded from his torpedoes.
Through the lens, he saw lifeboats lowering, men jumping into the water.
Then he saw the destroyer escorts race in, ignoring the survivors, hunting only for his submarine.
They dropped 104 depth charges over 6 hours, nearly crushing Harter’s hull.
When it was over, De surfaced to find oil slicks and debris.
The survivors from the freighter had drowned while their own destroyers tried to kill him.
In his private journal that night, Dei writes, “The destroyers are the real enemy, not the merchant ships.
The destroyers kill our boats.
If we could eliminate the destroyers, we could devastate their supply lines, but we’re trained to run from them.
What if we hunted them instead?” It’s a heretical thought.
Destroyers are designed to kill submarines.
They’re faster, more maneuverable, bristling with depth charges and sonar.
The TypeD destroyer carries 36 depth charges and can sprint at 34 knots.
USS Harder’s maximum surface speed is barely 20 knots.
Underwater, she can only manage 9 knots for short bursts before the batteries die.
Every tactical manual says the same thing.
Avoid destroyers or die trying.
But lying in his bunk that night, Dy remembers something from his years on destroyers.
In 1935, he served aboard USS Wrathburn during anti-ubmarine exercises.
He learned how destroyer captains think, how they hunt, and he realized their greatest weakness.
They expect submarines to run away.
“What if we didn’t run?” De asks his executive officer, Frank Lynch, the next morning, “What if we attack them head on?” Lynch looks at him like he’s lost his mind.
The Navy calls that a down the throat shot, Captain Training says it’s impossible to pull off.
Training also said our torpedoes work perfectly.
Training was wrong about that.
The problem is the geometry.
When a destroyer comes straight at you, the target profile is only 30 ft wide.
Our torpedo spread can’t guarantee a hit.
And if we miss, if we miss, we die.
I know.
De pulls out a notebook covered in calculations and diagrams.
But I’ve been working out the math.
If we wait until they’re close enough, so close they can’t possibly miss us with sonar, then our torpedoes can’t miss either.
At 1,000 yards, the spread pattern covers exactly the destroyer’s width.
We fire three fish.
At least one will hit.
You’re talking about letting a destroyer charge to point blank range.
That’s insane.
It’s unexpected.
Which means it might work exactly once before they figure it out.
And if it doesn’t work, De closes his notebook.
Then someone else will have to figure out how to sink these destroyers because Frank, we’re losing this war.
Not on the macro scale.
I know we’re winning island by island, but down here in our world, we’re losing.
The boats keep going out and not coming back.
If there’s even a chance this works, he doesn’t finish the sentence.
He doesn’t have to.
On June 6th, 1944, USS Harter surfaces off Tawittowi just before dawn.
De scans the horizon through his binoculars, searching for enemy contacts.
What he sees makes him grab the periscope handles.
Frank, get up here.
You need to see this.
Through the lens, destroyers, three of them, heading straight for Harter’s position.
And beyond them, barely visible in the morning haze, the massive silhouettes of battleships and carriers filling the anchorage.
My god, Lynch whispers.
The entire Japanese fleet.
De’s mind races.
This is intelligence worth dying for.
They need to radio Pearl Harbor immediately.
But the destroyers have spotted their periscope.
They’re closing fast, their boughs raising white spray as they accelerate.
Standard doctrine.
Dive to 400 ft.
Go silent.
Let them pass.
Dele’s hand hovers over the dive alarm.
Then he remembers the 52 submarines that followed standard doctrine.
That didn’t come home.
Battle stations, he says quietly.
I’m going to kill one of these destroyers.
Then we’re going to run like hell and tell Admiral Nimttz what we found.
June 6th, 1944.
So 800 hours.
The Japanese destroyer Minatsuki charges toward USS Harter’s periscope at 30 knots.
On her bridge, Commander Kato Shinsaku has spotted the American submarine and intends to ram it before it can dive.
It’s standard anti-ubmarine tactics.
Force the sub down, then pepper the water with depth charges until oil and debris surface.
What Commander Ko doesn’t know is that Sam De has no intention of diving.
Range De’s voice cuts through the tension in Harter’s control room.
1,000 yards and closing, Captain.
Every man holds his breath.
The destroyer’s screws are audible now through the hull, a rhythmic thrashing that grows louder by the second.
In conventional attacks, submarines fire at 4,000 to 5,000 yd, then immediately dive to escape.
At 1,000 yd, there’s no time for escape.
If the torpedoes miss, Minatsuki will be right on top of them.
Bearing, Die’s hands are steady on the periscope.
347 relative.
Dead ahead, sir.
Through the periscope, De sees Minatuki’s bow wave.
The destroyer looks massive from this angle, a wall of gray steel racing toward them.
He can see sailors on deck.
Can see the muzzles of her deck guns.
900 yd.
In the forward torpedo room, three Mark1 14 torpedoes weight in their tubes.
Each fish carries 680 pounds of Torpex explosive.
Each costs $10,000 to manufacture.
Each has a 50% chance of failing.
If even one of the three hits, the destroyer will break in half.
If all three fail, 800 yd.
Deal does something his trainers never taught him.
Instead of watching the destroyer through the periscope, he closes his eyes and visualizes the geometry.
The torpedo spread diverges at exactly 2°.
At this range, that creates a pattern 150 ft wide.
The destroyer is 380 ft long, but only 34 ft wide from this angle.
The math is brutal.
He needs to be closer.
700 yd.
Captain, we need to fire or dive.
Lynch’s voice rises.
They’re going to ram us.
De opens his eyes through the periscope.
Minatuki fills his entire field of view.
He can see the bow wave breaking around her hull.
He can see the muzzle flashes as her forward guns open fire.
The shells splashing into the water near their periscope.
600 yd.
Fire one.
Fire two.
Fire three.
Three compressed air charges blast the torpedoes out of their tubes.
They leap into the water, propellers spinning up to 46 knots.
The submarine shutters.
Dive.
Take her to 400 ft.
Rig for depth.
Charge.
Harder’s bow tilts down sharply.
The crew grabs pipes and rails as the submarine plunges.
The depth gauge spins.
50 ft.
100 ft.
150.
Time to impact.
17 seconds.
200 ft.
Deal.
Doesn’t need to count.
He’s done the math 100 times in his notebook.
17 seconds at 46 knots means his torpedoes will travel exactly 450 yards before womb.
The explosion shakes harder so violently that men are thrown against bulkheads.
Light bulbs shatter.
Cork insulation rains down from the ceiling.
Hit.
We got a hit.
Someone shouts.
But De is already yelling, “Blay that.
Keep diving.
Silent running.
Because hitting the destroyer is only half the battle.
Now they have to survive what comes next.
Above them, Minatsuki’s hull splits open just forward of her bridge.
The destroyer’s bow tears away, flooding the forward compartments.
She slew to starboard, her screws still churning uselessly as she begins to sink.
But her two sister ships are already racing toward Harder’s last known position, 300 ft.
Through the hull, they hear another sound.
The splash of depth charges hitting the water.
Brace for the first depth charge detonates 200 ft above them.
Then another, then six more in rapid succession.
The explosions feel like a giant hammer smashing the submarine’s hull.
Men grab onto anything bolted down.
The lights flicker and die, plunging the control room into darkness, except for the red battle lanterns.
In the dark, Dele’s voice stays calm.
Damage report.
Hydraulic system compromised.
The chief engineer calls out.
Lost pressure on the stern planes.
Manually compensating.
Oxygen down to 60% reserves.
Captain, they’re hurt.
The secret workshop where De tested his theory, the notebook full of calculations, the private drills with his torpedo crews.
It all worked, but barely.
They got one kill.
And now they’re trapped beneath two very angry Japanese destroyers with failing hydraulics and limited air.
That’s illegal, Lynch whispers, staring at the depth gauge.
What we just did? The Navy would court marshall you if they knew.
De wipes sweat from his forehead.
His hands are shaking now that the adrenaline is fading.
Frank, you know what else is illegal? Sending men out to die with defective torpedoes and outdated tactics.
We just proved this works.
Now we need to survive long enough to do it again.
Above them, the depth charges continue falling, but Harter slips away into the dark Pacific depths, leaving Minitsuki bubbling down to the ocean floor.
When the crew surfaces 4 hours later to ventilate the boat, they’re exhausted, terrified, and exhilarated.
They’ve just done the impossible.
And waiting for them above the horizon, four more Japanese destroyers, all hunting for the submarine that killed Minitsuki.
June 7th, 1944.
0600 hours.
Sam De composes the most important radio transmission of his career.
His hands still shake from yesterday’s depth charging.
Around him, USS Harter’s crew makes emergency repairs to the hydraulic system.
They should be running for safety.
Instead, DY writes, “Urgent discovered Japanese mobile fleet anchored Tawitawi.
Estimate two battleships, five carriers, 13 cruisers, 30 plus destroyers.
Sank destroyer Minatsuki engaging with down the throat tactics, continuing patrol harder.” He hands the message to his radio man.
Send it in the clear if you have to.
Pearl needs this now.
The response comes 90 minutes later.
It’s not from Admiral Lockwood.
It’s from Captain John Cromwell, submarine operations commander for the Southwest Pacific.
Harter, return to base immediately.
Do not engage enemy destroyers.
Repeat, do not engage.
Your primary mission is intelligence gathering, not combat.
Confirm receipt.
Cromwell.
Frank Lynch reads the message over De’s shoulder.
Well, that’s clear enough.
De crumples the paper.
The Japanese fleet knows we spotted them.
They’ll move within 24 hours.
If we leave now, we lose track of them.
The invasion of Saipan starts in 8 days.
Admiral Spruent needs to know where this fleet is going.
Sam, this is a direct order to withdraw.
I’ll face the court marshal later.
Right now, there’s a destroyer out there that needs sinking.
De grabs the periscope handles, and I intend to give the Navy enough evidence that down the throat tactics work that they’ll have to change their doctrine, whether they like it or not.
What happens next will be debated in naval war college classrooms for decades.
At Zo 742 hours, USS Harter spots destroyer Hyanami searching for them.
Instead of evading, DE maneuvers to attack position.
At 1,150 yards, he fires three torpedoes down Hyanami’s throat.
Two hit.
The destroyer sinks in 4 minutes, her stern rising vertically before sliding beneath the waves.
By nightfall on June 7th, DIY has violated direct orders, sunk two destroyers using a suicidal tactic and triggered a crisis in the Japanese high command.
Aboard battleship Yamato anchored in Tawitawi.
Vice Admiral Ugaki Mati writes in his diary, “The American submarine threat has become intolerable.
In two days, we have lost two destroyers to a single enemy boat.
This submarine appears to be hunting our escort specifically.
A radical departure from their usual tactics.
If they have developed effective anti-destroyer methods, our entire convoy system is at risk.
June 9th, 1944, 1,400 hours in Pearl Harbor.
Admiral Lockwood’s office explodes in argument.
Cromwell has flown in from Brisbane specifically to demand De’s relief of command.
He’s ignoring direct orders.
Cromwell slams his fist on the desk.
He’s risking his boat and crew on cowboy tactics that are going to get them killed.
I want him pulled off patrol immediately.
Lockwood holds up two patrol reports.
In two days, Commander De has sunk two Japanese destroyers.
Confirmed kills.
That’s more destroyers than the entire submarine force sank in the previous two months.
His tactics may be unorthodox, but the results speak for themselves.
The results are lucky survival.
Cromwell’s face reens.
The down the throat shot has a documented 10% success rate.
He’s three for six on torpedo hits, which is either blind luck or suicidal overconfidence.
Either way, the next time he tries this, they’ll be scraping Harter’s hull off the ocean floor.
The room erupts.
Officers take sides.
Voices rise.
Someone mentions USS Wahoo, which tried aggressive tactics under Commander Dudley Mush Morton and was lost with all hands in October 1943.
Others counter that Morton’s loss was due to shallow water operations, not tactical aggression.
Captain Richard Voge, Lockwood’s operations officer, stands up.
Gentlemen, the question isn’t whether De’s tactics are risky.
Of course they’re risky.
The question is whether they work.
And more importantly, can we afford to keep losing submarines while following conservative doctrine that isn’t working? Lockwood raises his hand for silence.
De reported discovering the Japanese mobile fleet at Tawi Tawi.
Intelligence confirms that’s their primary anchorage.
If his information is accurate, and if he can track their movements, we can intercept them before they reach the Maranas.
That intelligence alone is worth 10 submarines.
And if he gets himself killed, Cromwell demands, then he gets himself killed.
Lockwood meets his gaze.
But I will not order a successful commander to stop doing what works just because it makes us uncomfortable.
De has sunk more enemy destroyers in two days than most boats sink in their entire patrol.
Until he fails, I’m letting him continue.
This is madness.
This is war, Captain.
Lockwood’s voice goes ice cold.
And in war, we don’t get to choose between safe options and dangerous options.
We choose between losing slowly with conservative tactics or winning quickly with aggressive ones.
I choose winning.
The room falls silent.
Lockwood turns to his radio man.
Send a harder.
Continue mission.
Weapons free.
Sync enemy destroyers at your discretion.
Good hunting.
Lockwood.
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Now, back to Sam De’s war.
9,000 mi away, Sam De receives Lockwood’s message while stalking his third destroyer.
He shows it to Lynch.
Well, Lynch says quietly, “Now we really have to make this work.” De nods.
Frank, we’re about to find out if I’m a tactical genius or just the luckiest idiot in the Pacific.
June 9th, 1944, 1645 hours.
Destroyer Tanakazi charges toward their position.
De lets it close to 1,200 yards, fires, two hits.
Tanakazi breaks in half.
Three destroyers in 4 days.
The Japanese Navy has never seen anything like it.
And they’re about to make a decision that will change the entire Pacific campaign.
June 10th, 1944.
Zo 530 hours.
Sam Dy hasn’t slept in 48 hours.
USS Harter’s crew runs on adrenaline and coffee.
The hydraulic system is held together with patch welds and prayers.
Oxygen reserves sit at 43%.
Standard procedure says to surface, ventilate the boat and withdraw to safety.
Instead, de surfaces just long enough to recharge batteries and send another report to Pearl Harbor.
The message includes precise specifications, attack ranges, torpedo spread patterns, success rates.
He’s not just sinking destroyers.
He’s documenting exactly how to kill them.
The data is revolutionary.
Conventional longrange attacks 4,000 to 5,000 y% hit rate dealies down the throat tactics 900 1/200 yd 67% hit rate destroyer kill ratio.
Three sunk, six torpedoes fired.
Submarine survival rate 100% so far.
But the real test comes at dawn.
Through his periscope, De spots something that makes his stomach drop.
Not one destroyer, not three.
Six Japanese destroyers in formation conducting a coordinated search pattern, hunting specifically for him.
And behind them, moving out of Tawi Tawi anchorage, battleships Yamato and Mousashi, the two largest warships ever built.
The Japanese aren’t just hunting anymore, they’re fleeing.
Captain, that’s a full convoy escort, Lynch warns.
And they’re searching with sonar.
They know we’re here.
De studies the formation through the periscope.
The destroyers are spread in a picket line, their sonar pinging constantly.
Behind them, the battleships move slowly, cautiously, protected by layers of escorts.
The entire Japanese mobile fleet is evacuating Tawi Tawi, abandoning their hidden base because of one American submarine.
Operation Khan, the Japanese plan to reinforce their garrison at Byak and draw the American fleet into a decisive battle is falling apart.
Without their secret anchorage, the Japanese Navy has nowhere to stage for the offensive.
But De doesn’t know this yet.
All he knows is that six destroyers are hunting him.
And if he doesn’t stop them, they’ll sink harder.
We’re going after the lead destroyer.
Deal announces.
Sir, that’s suicide.
Lynch’s voice cracks.
We can’t possibly Frank, count the destroyers.
Six.
Now count our torpedo tubes.
Six forward tubes.
If we can reload fast enough, we might sink all of them.
Or they might sink us trying.
Then we better not miss.
June 10th, 1944.
0635 hours.
The lead destroyer is Kazagumo, commanded by Lieutenant Commander Tokuno Manoru.
He’s received specific orders from Vice Admiral Ugaki.
Locate and destroy the American submarine terrorizing our forces.
The honor of the Imperial Navy depends on eliminating this threat.
Takuno is a veteran destroyer commander with 8 years experience.
He knows submarine tactics.
He’s trained specifically for anti-ubmarine warfare.
And he’s confident that this American boat, operating alone, damaged from previous encounters, running low on supplies, will follow standard evasion procedures.
He’s about to learn that Sam De doesn’t follow any procedures.
Sonar contact bearing 035, range 20,000 m.
Kazagumo’s sonar operator shouts.
Tokuno smiles.
The submarine has made a mistake, staying too shallow.
All ahead flank prepare depth charges.
Kazagumo surges forward, her bow wave rising as she accelerates to 32 knots.
Behind her, the other five destroyers maintain formation, ready to box in the submarine once Kazagumo forces it down.
What Tokuno doesn’t see, USS Harter isn’t running.
She’s maneuvering into attack position.
Range 1,500 yd.
Dei calls calmly.
Through the periscope, he watches Kazigumo charge straight at him.
The geometry is perfect.
The destroyer’s bow points directly at Harter’s tubes.
1,000 y.
Sir, two more destroyers are closing from Starbird.
De ignores them.
Once you commit to a down the throat shot, there’s no backing out.
You hit or you die.
Standby tubes.
One, two, three, 800 yards.
Through the periscope, De sees sailors on Kazagumo’s deck preparing depth charges.
They expect him to dive any second.
They expect him to run 700 yd.
Fire one, fire two, fire three.
Three.
Mark 14.
Torpedoes leap from Harter’s tubes, racing toward Kazagumo at 46 knots.
Dei doesn’t wait to see if they hit.
Emergency dive.
Take her to 400 ft.
Harter’s bow drops.
The depth gauge spins.
And aboard Kazagumo, the sonar operator screams a warning too late.
Lieutenant Commander Takuno has just enough time to realize his mistake.
The American submarine wasn’t running.
It was attacking before two torpedoes slam into his hall.
The explosions tear Kazagumo in half.
Her forward section floods instantly.
Her stern rises, propellers still spinning as 240 sailors scramble for the deck.
The destroyer sinks in 90 seconds.
The Japanese Navy will later record in their official reports.
The American submarine employed a tactic never before encountered, attacking surface escorts headon at pointblank range.
Defensive measures proved ineffective.
But USS Harter’s battle isn’t over.
Five destroyers remain and all of them are converging on her position.
For six hours, Harter endures the most intensive depth charge attack of the war.
The Japanese drop 149 depth charges, turning the water into a killing zone.
Inside the submarine, men pray silently as explosions shake the hall.
Cork insulation disintegrates into snow.
Pipes burst.
The temperature climbs to 110° F.
Oxygen levels drop to dangerous lows.
Men gasp for breath, their vision tunneling.
Hydrogen reading is critical in the battery compartment, the engineer reports.
One spark and we’re dead.
De sits on the deck of the control room, his back against the bulkhead, calculating.
They can’t surface.
Destroyers wait above.
They can’t run.
The batteries are nearly dead.
They can’t hide.
Japanese sonar has them locked.
But then at hours, the depth charging stops.
Through the hull, they hear the destroyer screws fading into the distance.
Why are they leaving? Lynch whispers.
They had us dead to rights.
The answer comes hours later when Harter finally surfaces and intercepts Japanese radio traffic.
The Imperial Navy is withdrawing the entire mobile fleet from Tawitawi.
They’re abandoning their secret base.
Operation Khan is canled.
The Japanese battleships and carriers are retreating northwest away from American intelligence.
But Allied codereakers are reading their signals.
Admiral Spruent now knows exactly where the Japanese fleet is heading.
The Philippine Sea, where seven American aircraft carriers wait to spring the trap.
June 21st, 1944.
USS Harter limps into Darwin, Australia for emergency repairs.
She’s barely afloat.
Her hull is cracked in six places.
The hydraulic system is destroyed.
Oxygen tanks are empty, but draped across her conning tower, four Japanese battle flags, one for each destroyer she’s killed.
De steps onto the dock to find a crowd of submariners waiting.
These are veterans from other boats.
USS Dace, USS Hado, USS Hake.
They know what Harter has accomplished.
They know the odds.
A chief petty officer from USS Dace approaches.
His eyes are red.
Sir, my boat lost three men last month to a destroyer attack.
We followed standard doctrine.
We ran when we should have and they still killed us.
He extends his hand.
De shakes it.
What you did out there? The chief’s voice breaks.
You proved there’s another way.
You proved we don’t have to just run and hide.
Some of us might make it home now because of what you figured out.
Behind him, dozens of submariners start clapping.
The sound echoes across the dock.
De stands there stunned.
He’s violated direct orders, defied conventional wisdom, risked his crew on tactics that couldn’t work.
And now these men, men who face death every time they leave port, are thanking him.
The rest of Sam De’s story gets even more intense.
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Now, the final chapter of USS Harter’s war.
The official data comes in over the next week.
Analysis confirms what De already knows.
Before Harter’s fifth patrol, US submarines versus Japanese destroyers.
12% success rate.
Average range of attack for 200 yards.
Destroyer kills per patrol.
0 point is a weight after Harter’s fifth patrol.
Down the throat tactic success rate 67% when executed properly.
Optimal attack range 900 1,200 yd.
Harter’s kill rate four destroyers in 4 days.
The impact on Japanese operations is immediate.
Vice Admiral Ugaki writes in his diary on June 12th.
The loss of four destroyers to a single American submarine has forced reconsideration of our entire operational plan.
We cannot maintain forces at Tawittowi.
Under these circumstances, the submarine threat exceeds all projections.
On June 19th, 1944, the Battle of the Philippine Sea begins.
American carrier aircraft slaughter Japanese planes in what pilots will later call the Great Mariana’s Turkey shoot.
The Japanese lose three carriers and 600 aircraft.
It’s the decisive naval victory of the Pacific War.
It happens because the Japanese fleet was forced to abandon their hidden anchorage at Tawi Tawi, forced to operate in waters where American submarines could track them.
All because Sam De and USS Harter proved that one submarine using impossible tactics could terrify an entire Navy.
By the end of June 1944, every American submarine in the Pacific receives new tactical guidance.
The down the throat shot is no longer forbidden.
[clears throat] It’s doctrine.
Submarines are authorized, encouraged to engage Japanese destroyers aggressively.
The destroyer killer tactics pioneered by Harter become standard training.
The war has changed and Sam De changed it one impossible shot at a time.
August 24th, 1944.
Zo 730 hours.
USS Harter submerges for the last time.
She’s on her sixth war patrol operating in a Wolfpack with USS Hatau and USS Hake off the coast of Luzon, Philippines.
Commander De has just received orders to investigate Japanese convoy movements in Daol Bay.
What he doesn’t know, Japanese mind sweeper CD22 is patrolling these exact waters, specifically hunting for American submarines.
At Asia Wait 22 hours, CD22’s sonar detects harder at 300 ft depth.
The Japanese ship drops a perfect depth charge pattern.
18 charges explode simultaneously around Harter’s Hall.
The submarine implodes.
79 men, Sam Dy, Frank Lynch, and the entire crew that revolutionized submarine warfare die instantly at 1,040 m depth.
The US Navy declares USS Harter missing on October 2nd, 1944.
She’s officially presumed lost on January 2nd, 1945.
Commander Samuel David Deedged 37 is postumously awarded the Medal of Honor on November 15th, 1945.
President Harry Truman presents the medal to Dele’s widow, Edwina at a White House ceremony.
The citation reads, “For conspicuous gallantry and intrepidity at the risk of his life, attacking Japanese destroyers with a daring that bordered on the reckless.
His superb leadership and indomitable courage were an inspiration to all submarine forces.
But the real legacy appears in the statistics.
USS Harter’s war patrols, ships sunk, 18 confirmed postwar analysis.
Tonnage 54,2 tons destroyers sunk.
Five most of any submarine in WW Ton patrols conducted six presidential unit citation awarded days since launch to loss.
632 impact on US submarine doctrine.
By September 1944, down the throat tactics are mandatory training.
Destroyer kill rate improves from 12% to 34% by wars end.
52 Japanese destroyers sunk by American submarines after Harter proved it possible.
Estimated American lives saved.
3,000 plus submariners who returned home using De’s tactics.
In 1945, Japanese records captured after the war reveal Vice Admiral Ugaki’s final assessment of USS Harter.
This single submarine accomplished what an entire task force could not, forcing the abandonment of our strategic anchorage and disrupting Operation Con.
The commander demonstrated tactical innovation that exceeded anything in our defensive planning.
His death was the first positive development in our anti-ubmarine campaign in months.
The US Navy names a destroyer escort USSD de honor in 1954.
The ship serves until 1973, pioneering new anti-ubmarine technologies, a fitting tribute to a man who revolutionized submarine tactics.
In 2024, 80 years after her loss, USS Harter’s wreck is finally discovered by the Lost 52 project at 3,000 ft depth off the coast of Luzon.
The submarine lies intact.
Her bow still pointed forward as if charging into battle.
No bodies are recovered.
Harter remains a war grave, protected by international law.
Modern submarine commanders still study De’s patrol reports at Naval Submarine School in Groten, Connecticut.
The lesson they learn, sometimes the impossible tactic becomes the winning tactic if someone has the courage to try it.
A plaque at the Submarine Force Museum reads, “Cruel Dy, destroyer killer.
He taught us that submarines don’t have to hide from surface ships.
Sometimes they should hunt them.
Lieutenant Commander Frank Lynch’s final letter to his wife, written the night before Harter’s last patrol was recovered from his shorebased belongings.
Sam keeps pushing the limits of what submarines can do.
Some of the crew think he’s crazy, but I’ve watched him calculate every attack down to the yard.
The second, the degree of angle.
He’s not reckless.
He’s just fighting a different war than the one they taught us in school.
Whatever happens, I’m proud to serve with him.
Samuel David Dey never sought fame.
He refused interviews, declined publicity tours, and spent his brief shore leaves quietly with his wife and children in Perth, Australia.
Crew members later recalled that he never bragged about his kills, never displayed bravado.
When asked by Admiral Lockwood during his fourth patrol why he took such risks, De replied simply, “Sir, 52 boats haven’t come home.
That’s 4,000 men who did everything by the book.
If the book isn’t working, someone has to write a new one.” He wrote it in torpedo trails and sinking destroyers.
He wrote it in tactical reports that rewrote naval doctrine.
and he wrote it in the survival of countless submariners who came home using the tactics he proved worked.
The lesson of USS Harter endures in war, as in life, the most dangerous phrase is that’s impossible.
Sometimes the only difference between impossible and inevitable is one person willing to prove everyone wrong.
Five Japanese destroyers rest on the Pacific floor.
Testament to a commander who refused to accept that submarines couldn’t hunt the hunters.
And somewhere in the dark waters off Luzon, USS Harter sits upright at 3,000 ft.
Her torpedo tube still aimed forward, forever poised for the attack that never came.
Hit him harder.
Her motto echoes still in every submarine that learned to fight instead of hide.
