The U.S. Army Didn’t Believe It: Tanks Sank 5 Ships With Zero American Losses

The Night Tanks Sank a Navy: Ormok Bay’s 18-Minute Annihilation

At 11:55 p.m. on December 11th, 1944, five Japanese ships slipped toward the shore of Ormok Bay.

They were not racing. They were not zigzagging. They moved with the slow confidence of ships that had done this before and gotten away with it.

They had reason to be confident.

Nine major convoys had already forced their way into this same bay. More than 34,000 Japanese soldiers had reached Leyte through this water. Every night another handful of battered transports and barges would sneak in, unload men and supplies, and slip back out into the dark.

Tonight was supposed to be no different.

Another landing.
Another reinforcement.
Another delay to the American advance.

Nothing on the surface of the bay looked unusual.

And that was the mistake.

Because less than twenty minutes later, all five of those vessels would be gone.

Not damaged. Not driven off. Destroyed—sunk or shattered beyond use—by a weapon that, on paper, had no business firing at ships at all.

Three American tank destroyers.
Fifteen rounds.
Eighteen minutes.
Zero American casualties.

It sounds wrong. It should sound wrong.

Tank destroyers are not naval weapons. Infantry divisions do not fight navies. That’s not how modern war is supposed to work.

In 1944, every field manual in the U.S. Army agreed.

Reality did not.

A Claim So Absurd Washington Didn’t Believe It

Weeks later, a report landed on a desk in Washington. Stripped of drama, stripped of context, reduced to numbers, it said this:

Rounds fired: 15
Enemy vessels destroyed: 5
Engagement duration: 18 minutes
Friendly casualties: 0
Estimated enemy casualties: 750
Location: Ormok Bay, Leyte, Philippines
Reporting unit: 77th Infantry Division, U.S. Army

To anyone who understood how the war was supposed to work, it looked like a mistake or an exaggeration.

Tanks didn’t sink ships.

Not in Europe.
Not in the Pacific.
Not anywhere.

If Japanese shipping was stopped, that was the Navy’s job—destroyers, cruisers, submarines, patrol torpedo boats, aircraft. The Army’s job was to fight on land, dig foxholes, take hills.

Infantry divisions were not supposed to be calculating range and deflection on moving targets over open water at midnight.

But by December 1944, Ormok Bay was no longer a normal place.

The Funnel of Death

On most maps, Ormok Bay was an insignificant dent on the western shore of Leyte. No towering cliffs, no famous beaches, no postcard scenery.

By December, it was the most dangerous water in the Philippines.

It was the last door.

American aircraft dominated the skies by day. Destroyers and cruisers prowled the sea by night. Eastern approaches were shut down. Mountain roads were ambush corridors and death traps.

That left Ormok Bay as the only route where the Japanese could still move troops in bulk.

From late October to December 11th, the Imperial Japanese Army tried nine major reinforcement runs into this funnel. Not small barges. Not single boats. Convoys.

They pushed roughly 34,000 troops through that bay, and they paid for it in blood and steel:

At least 20 transports sunk
6 destroyers lost
1 submarine
3 escorts
1 patrol boat

The Americans bled there, too—destroyers and landing ships lost or crippled.

Naval historians would later call Ormok one of the most brutal sustained interdiction battles in the Pacific.

And still the Japanese came.

General Tomoyuki Yamashita had decided that Leyte mattered. If the Philippines could be contested long enough, the U.S. timetable would slip everywhere. Delay itself was a form of victory.

If that meant losing ships night after night to get even half a load of troops ashore, so be it.

Ormok Bay stayed open by sheer force of will.

Until an Army infantry division quietly turned it into a trap.

The “Old Bastards” and a Cold-Blooded Doctrine

The unit holding Ormok town on the night of December 11th wasn’t some elite, hand‑picked spearhead.

On paper, it was almost the opposite.

The 77th Infantry Division—reactivated in 1942, filled mostly with men from New York and New Jersey—had an average age of 32. In an army where nineteen- and twenty‑year‑olds carried most of the rifles, that stood out.

Other units had a name for them:
The “Old Bastards.”

The nickname stuck. The men didn’t fight it. Many had been taxi drivers, accountants, factory workers. Men who’d raised families, survived the Depression, paid bills. Men who understood cost.

And when they learned war, they treated it like a problem to be solved, not a stage for heroics.

The division’s numbers prove it.

Across the Pacific, American forces killed about 2.2 million Japanese soldiers and captured roughly 50,000—a capture rate of about 2.2%.

The 77th killed over 43,000 and captured just 358: a capture rate of 0.8%, one-third the theater average.

On Leyte alone, in six weeks, they killed 19,456 Japanese and captured 124.

That’s not the pattern of a unit throwing bodies at problems.

It’s the pattern of a unit that lets firepower do the killing and refuses to waste men.

At the top of that doctrine was Major General Andrew D. Bruce, a 49‑year‑old career artillery officer who believed in mathematics, not slogans.

No bayonet‑charge romanticism. No “take that hill at any cost” rhetoric.

His rules were simple:

Let artillery and heavy weapons do the work
Avoid frontal assaults when possible
Go around strongpoints instead of through them
Infantry exists to occupy ground, not to die proving bravery

It looked cold. It was efficient.

It also worked.

Guam fell in August 1944 with casualty ratios that stunned observers. On Leyte, when Bruce was told to land south of Ormok on December 7th, he didn’t charge straight in.

He landed 3½ miles away, where the Japanese didn’t expect it. The 77th advanced 23 miles in 72 hours, smashed through defenses, and took Ormok town by December 10th.

But the ships kept coming at night.

And field manuals had no chapter on what to do when the enemy navy was landing troops right in front of an Army division.

Doctrine Breaks. Math Takes Over.

On paper, the situation was unsolvable.

The Navy couldn’t cover every shallow bay at all times
PT boats were effective but spread thin
Aircraft were blind at night without illumination
Infantry divisions weren’t equipped as coastal defense forces

By the book, that meant stalemate—Japanese troops continuing to land under cover of darkness, American casualties mounting in the hills.

The 77th didn’t see a doctrinal problem.

They saw an equation:

If ships reach the beach → men disembark.
If men disembark → Americans die later.
Therefore ships must not reach the beach.

Who stops them doesn’t matter.
What weapon does it doesn’t matter.
What the manual says really doesn’t matter.

So the division turned Ormok into a layered kill zone using whatever it had:

M10 tank destroyers with 3‑inch guns
105mm self‑propelled howitzers
40mm anti‑aircraft guns
Mortars for illumination
Machine guns to finish survivors in the water

They didn’t improvise in the moment. They planned for it.

By 11:55 p.m. on December 11th, the men along the waterfront were already in position. Orders had gone out twenty minutes earlier:

Track the vessels.
Wait for illumination.
Fire on command.

Eighteen Minutes

The bay was black. The shapes of five Japanese vessels moved slowly across the water: two transports, three barges, heavily loaded, forced by shallow depth to crawl into the kill zone.

No one on shore knew for sure if what they were about to try would work.

The M10 tank destroyers had been built to kill German tanks—tough, armored, brutal machines.

No one had ever fired them at ships.

They were open‑topped, vulnerable to artillery and small arms. Firing them in full view of enemy vessels was a risk.

It was a calculated risk.

At exactly midnight, a 60mm mortar fired an illumination round. It climbed, arced, and burst 300 feet above the bay in a ball of white.

In an instant, Ormok Bay stopped being darkness and became geometry.

Distances snapped into focus.

The lead transport—later identified as No. 159—materialized in perfect silhouette: roughly 200 feet long, about 800 tons, hull plating under an inch thick.

A designed to carry men, not survive armor‑piercing gunfire.

The M10 crews had seconds before the flare burned out.

They loaded.
Aimed at the waterline.
Fired.

A 3‑inch armor‑piercing round left the barrel at about 2,600 feet per second. Range: roughly 970 yards. Time of flight: just over one second.

The recoil drove the 17‑ton vehicle half a foot back into the sand.

The shell smashed through the starboard hull just above the waterline, tore through the cargo space, detonated against the port side.

Inside, it was instant catastrophe. A ragged hole opened. Water poured in at a rate no pumps could possibly match. The ship began to list, stern dropping, decks tilting.

It was still afloat. Still moving. For the moment.

Forty seconds later, another illumination round turned the bay into daylight again.

By then, the first transport was already dying.

The second 3‑inch round struck lower—below the waterline. A second breach. Flooding multiplied. The ship’s fate was no longer tactical. It was mathematical.

The M10s shifted targets.

The 105mm howitzers walked high‑explosive shells across the second transport, ripping open superstructure, shredding exposed troops.

Forty‑millimeter Bofors guns, designed to tear apart aircraft, chewed into wooden barges. One barge disintegrated in twelve seconds under explosive fire. Another turned to splinters when a 3‑inch shell hit it amidships.

The third grounded in shallow water less than 100 yards from shore. Men jumped, tried to wade, and were cut down by machine guns waiting for precisely that moment.

From the first flare to the last shot, eighteen minutes passed.

Five Japanese vessels destroyed.
Roughly 750 enemy troops killed.
American casualties: none.

There were no speeches. No dramatics. Just weapons doing what they were capable of doing, even though no one had ever asked them to do it this way before.

Steel Doesn’t Lie

In January 1945, with the fighting already moving on, the U.S. Army did something unusual.

It doubted itself.

An infantry division claiming to have sunk multiple enemy vessels with tank destroyers was not something you just file away.

If the report was wrong, it had to be corrected.
If it was right, the Army had a capability it had never documented.

Investigators went to Ormok Bay. At low tide, the water was clear, the wrecks within reach.

They found Transport No. 159 in about fifteen feet of water. The hull was damaged but intact enough to study.

They measured two clean holes on the starboard side, both about three inches in diameter, both below the waterline.

The angle of entry matched the known shore positions of the M10s. The spacing matched the firing logs.

Steel had kept the receipts.

The second transport lay deeper, but divers found three penetrations: two consistent with 3‑inch AP rounds, one with a 105mm HE shell. Fragments raised from the seabed matched rounds manufactured at Watervliet Arsenal in New York in 1944.

There was no room for mythmaking.

The after‑action report was accurate.
The timeline was accurate.
The results were real.

One infantry division had, in fact, used its tank destroyers to sink enemy ships from shore.

It was the only confirmed instance of its kind in the entire Second World War.

Tanks had never sunk ships before.

They never would again.

A Door Slams Shut

The Japanese tried again on December 12th—two barges. They died in minutes.

They tried again on December 13th—one larger transport and three barges. The transport went down in twelve minutes. The barges never got within a thousand yards.

Three nights. Around 1,300 Japanese troops killed at sea. Zero Americans lost.

Then the convoys stopped.

Not because of fear. Because the numbers stopped making sense.

Ormok Bay no longer offered delay in exchange for ships and men. It offered total loss for no gain. No troops ashore. No supplies delivered. No time bought.

Yamashita could tolerate slaughter so long as it purchased something.

Now it purchased nothing.

The funnel closed.

In the mountains inland, Japanese units that had been hanging on by a logistical thread began to starve—of ammunition, of food, of medical care, of hope. The 77th advanced north from Ormok. Resistance didn’t vanish; it frayed.

By Christmas, Leyte was effectively secure. The statistics are stark:

19,456 Japanese killed by the 77th on Leyte
124 captured
American casualties: 543 killed, 469 wounded
Roughly 36 enemies killed for every American killed

Those numbers don’t include the men who never made it off the ships—ghost battalions drowned in Ormok Bay before they could ever fire a shot.

A Capability No One Planned For

In March 1945, the Army updated the technical manual for the M10 tank destroyer.

They added a small section:
“Employment Against Naval Targets.”

Three paragraphs.

It noted that 3‑inch armor‑piercing rounds could penetrate unarmored vessels at up to 1,000 yards. It recommended aiming at the waterline to maximize flooding. It cited Ormok Bay as the reference.

No boldface. No fanfare. Just a quiet admission: reality had revealed something the designers had never bothered to imagine.

The war moved on. There would be no more Ormoks—no more chances for shore‑based tank destroyers to ambush troop convoys at knife‑fighting range. Okinawa’s defenders were already in place. The Japanese navy was nearly gone.

The M10 crews who fired those fifteen rounds went on to other battles. Most never spoke much about sinking ships. To them, it was just another night where the math said “fire” and they obeyed.

Today, Ormok Bay looks ordinary on a map again. The water is calm. The wrecks lie under silt and coral.

But for eighteen minutes in December 1944, that bay became the place where an infantry division quietly rewrote what its weapons could do—and slammed shut the last door the Japanese had left on Leyte.

It is the only time in history that tanks sank a navy.

And it happened because a group of “old bastards” decided that doctrine mattered less than what happened when high‑velocity steel met thin metal at the waterline.