The ocean was a shroud of ink, a suffocating weight of three thousand fathoms pressing against the steel ribs of the USS England. At 0150 hours on May 19th, 1944, the air inside the Combat Information Center was thick with the smell of unwashed bodies, stale coffee, and the ionizing ozone of the radar sets. Lieutenant Commander Walton Pendleton stood like a statue, his eyes fixed on the glowing green sweep of the sonar scope. Every ping was a heartbeat. Every return was a ghost. Somewhere beneath those black, rolling swells of the South Pacific, a Japanese titan was prowling—the I-16—unaware that the mathematics of death were already being calculated above.
Pendleton was thirty-seven years old, a man of cold logic in a war of hot blood. This was his first patrol as a commanding officer, and his scoreboard was a haunting zero. No kills. No glory. Just the relentless ticking of a clock and the terrifying responsibility for the lives of his crew. The Japanese Imperial Navy had laid a trap, a lethal scouting line of seven submarines across the path to the Marianas, and Pendleton was the man sent to break it. He watched his sonar operator, whose fingers hovered over the dials with trembling precision, tracking a contact moving at a sluggish six knots beneath the surface north of Bougainville.
The atmosphere was electric, a static charge of fear and anticipation that made the hair on the sailors’ necks stand up. They were aboard a Buckley-class destroyer escort, seventy-seven feet shorter than a fleet destroyer and built for one singular, brutal purpose: hunting submarines. But it wasn’t the ship’s size that mattered; it was the secret weapon mounted on her deck. Twenty-four spigot mortars, arranged in rows like the quills of an angry beast. The British called it the Hedgehog. Unlike the thunderous, chaotic depth charges of the past, the Hedgehog was a silent assassin. It didn’t explode on depth; it exploded on contact. If the crew heard nothing, they had missed. If they heard a roar, it meant they had struck the very heart of the enemy.
The stakes were higher than Pendleton could admit to his men. The statistics of anti-submarine warfare were a brutal testament to failure; over five thousand depth charge attacks by British forces had yielded a mere eighty-five kills—a one-in-sixty gamble. Submarines usually escaped in the fifteen minutes of sonar blindness caused by the explosions. But Pendleton didn’t believe in gambles. He believed in the mathematics of the Hedgehog. He believed in the decoded intelligence from the Fleet Radio Unit Pacific that placed the I-16 exactly in his sights. As the range closed to fifteen hundred yards, the sonar operator’s voice cracked the silence.
“Range fifteen hundred, sir! She’s diving!”
Pendleton didn’t flinch. He knew the Japanese commander was down there, twisting the iron coffin of his ship in radical turns, desperate to vanish into the abyss. The hunt had begun, and before the sun rose, the Pacific would either claim Pendleton’s reputation or swallow a hundred Japanese sailors in a tomb of crushed steel.
Lieutenant Commander Walton Pendleton stood in the cramped combat information center of the USS England, watching his sonar operator track a contact moving at 6 knots beneath the black waters north of Bougainville. At thirty-seven years old, this was Pendleton’s first war patrol as a commanding officer, and he carried the weight of a zero-submarine kill record. The Japanese Imperial Navy had stationed seven submarines in a scouting line across the route to the Marianas. England was a Buckley-class destroyer escort, 77 feet shorter than a fleet destroyer. Half the crew was built for one purpose: hunting submarines.
But the weapon that made her different sat mounted on her deck—24 spigot mortars arranged in rows. The British called it the Hedgehog. The projectiles fired 200 yards ahead of the ship in a circular pattern. They utilized contact fuses, meaning they only exploded if they hit something solid. Depth charges had been killing submarines for three decades, but they were a clumsy tool. A crew would roll them off the stern, set the hydrostatic fuse for an estimated depth, and hope the submarine was still there when the charges reached detonation depth.
The statistics told a brutal story. British forces had launched 5,174 depth charge attacks during the war, resulting in only 85 confirmed kills—one kill for every 60 attacks. By the time the charges sank, submarines had usually already moved. Furthermore, the explosions disturbed the water so badly that sonar became useless for fifteen minutes, allowing submarines to escape in the chaos. Hedgehog changed everything. Being forward-throwing, it allowed the ship to maintain sonar contact throughout the attack. These 65-pound projectiles, each packed with 35 pounds of Torpex, were silent misses. There was no water disturbance and no lost contact.
However, the numbers were still being proven. Early trials showed a mere 5% success rate, and many crews didn’t trust the new technology. Captains across the fleet preferred the familiar, bone-shaking thunder of depth charges. But Pendleton was a man who trusted numbers. He looked at the data: one Hedgehog kill for every five attacks versus one depth charge kill for every eighty. The mathematics were simple. Fleet Radio Unit Pacific had decoded Japanese submarine I-16’s transmission four days earlier. The intelligence was perfect: destination Bougainville, arrival time 2200 hours, May 19th. England and two sister ships had positioned themselves along I-16’s route. Now, the contact was real.
The sonar operator called out the range.
“1500 yards!”
The I-16 was diving, performing standard Japanese evasion tactics: radical turns and changing depth. The submarine commander knew he was being hunted. Pendleton ordered the first Hedgehog attack at 1341. Twenty-four projectiles arched through the afternoon sky, splashed into the Pacific, and sank at 23 feet per second.
Silence.
It was a miss. I-16 had turned. The second attack was ordered shortly after. This time, it scored one hit at 130 feet. The explosion lifted England’s bow, but it was not enough to destroy the vessel. A third attack was launched, but it missed. The fathometer revealed the problem: I-16 had gone deep, reaching 325 feet—deeper than Pendleton had estimated. During the fourth attack at 1433, the I-16 turned inside the pattern, resulting in another miss.
Pendleton remained calm, recalculating. During the fifth attack, four detonations were heard. Then six. A massive underwater explosion followed. The blast was so powerful it lifted England’s stern clear out of the water and knocked sailors off their feet. Twenty minutes later, debris began surfacing—oil, wood, and fabric. I-16 was gone, and 107 men were dead.
But the mission was far from over. Fleet Radio Unit Pacific had decoded another message. Seven more Japanese submarines were stationed in a patrol line north of the Admiralty Islands, and England was sailing straight toward them. Commander Hamilton Haynes received the decoded intelligence at Tulagi on May 20th. The Japanese 7th Submarine Squadron had deployed seven Type KO submarines along a line designated “NA.” The submarines were positioned at precise intervals from Truk Island to the waters west of Manus. These were the RO-104, RO-105, RO-106, RO-108, RO-109, RO-112, and RO-116.
Each submarine carried 56 crew members. Their mission was to detect American carrier task forces moving toward the Marianas or Palau Islands. Admiral Soemu Toyoda needed to know where the Americans would strike next; the submarines were his eyes. Haynes ordered England to join the destroyer escorts George and Rabie. Three ships against seven targets. The odds seemed impossible, but Pendleton had proven something in that first engagement with I-16. Five Hedgehog attacks had resulted in one kill—a 20% success rate, which was four times better than the early trials. The weapon worked.
The crew trusted it now. They had heard the explosions, watched the debris surface, and counted the oil slicks spreading across the Pacific. The hunting group departed Purvis Bay on May 21st. They maintained a standard line-abreast formation with 16,000 yards between ships during darkness. Radar sweeps were conducted every 30 seconds, and sonar was pinging continuously. The Japanese submarines were maintaining radio silence now, meaning there were no more transmissions to decode and no more precise coordinates. The hunter-killer group would have to find them the old way: electronic detection, patience, and mathematics.
Pendleton studied the charts in his cabin. The NA line stretched across Admiral Halsey’s previously used routes. The Japanese were predictable, stationing submarines where American forces had moved before, hoping the Americans would move there again. But Fleet Radio Unit Pacific had given the Americans an advantage the Japanese didn’t know existed. The Americans knew exactly where the picket line was positioned; the only question was timing. Submarine patrol patterns were predictable: surface at night to recharge batteries, dive at dawn, run submerged during daylight, and surface again after sunset.
The window for radar detection was narrow. Submarines were vulnerable on the surface, but they were fast. A submarine commander could dive in 60 seconds and be at 200 feet depth in three minutes, disappearing into the black water. England’s crew had drilled for this. Sonar operators could track a diving submarine, calculate depth, estimate speed, and predict position. The Hedgehog launchers could be loaded and fired in 90 seconds. With 24 projectiles covering a 130-foot circle 30 feet deep, every launch was a gamble, but the contact fuses provided certainty. If the projectiles exploded, they hit something. If they stayed silent, they missed.
The mathematics were simple but brutal. Seven submarines, 56 men per submarine, 392 Japanese sailors total. One Hedgehog attack could kill them all in nine seconds. At 0350 on May 22nd, George’s radar detected a surface contact at 15,000 yards. The first submarine of the line, RO-106, was recharging her batteries and never saw the destroyer escorts coming. George’s searchlight caught RO-106 on the surface, and the submarine crash-dived immediately. Seawater flooded her ballast tanks as her bow angled down. Within 90 seconds, she was submerged.
George fired Hedgehog at 0415. Twenty-four projectiles splashed into the dark water.
Silence.
It was a miss. England regained sonar contact at 0425 at a range of 1,400 yards. RO-106 was running deep and making radical turns. The Japanese commander knew the tactics: turn inside the attack pattern and change depth constantly to make the Americans guess. But Pendleton didn’t guess. His sonar operator tracked every turn, calling out depth changes, range, and bearing. The data fed directly to the Hedgehog firing solution.
The first attack missed because RO-106 had turned 30 degrees during the projectile sink time. Nine seconds was enough for a submarine to move 150 feet. A second attack was launched at 0501. The twenty-four projectiles formed their circular pattern and sank through the darkness. Three detonations were heard, followed by a massive underwater explosion. The pressure wave rolled across the surface, and England’s hull shuddered. George and Rabie felt it 4,000 yards away. At sunrise, the oil slick was half a mile wide, filled with floating debris, metal fragments, and wood. There were no survivors.
That was kill number two. Twenty-four hours after I-16, the three destroyer escorts reformed their line with 16,000-yard spacing and continued northeast along the NA line. The next submarine was out there—RO-104, RO-105, or any of the remaining five. Japanese submarine commanders maintained strict radio silence, but they surfaced on predictable schedules because batteries required recharging, electric motors needed power, and diesel engines needed air.
At 0600 on May 23rd, Rabie’s radar detected another surface contact at a range of 22,000 yards. The contact dove before identification. The Japanese commander had evidently learned something from RO-106’s death: stay deep and make them guess your depth. Rabie fired four Hedgehog attacks starting at 0617, but all were misses. RO-104 was turning inside the patterns. George tried next. Her first attack missed at 0717, and her second, third, and fourth attacks all missed between 0730 and 0810.
The Japanese submarine commander was skilled. Every time projectiles splashed above him, he turned and changed depth, making the mathematics seemingly impossible. Division Commander Haynes watched as England approached for her turn. Pendleton’s crew had two kills, while Rabie and George had none. The pattern was becoming clear: England’s sonar operators were better, her Hedgehog crews were faster, or Pendleton’s firing solutions were more accurate. Whatever the reason, England was the killer in this hunting group.
Haynes radioed five words that would become Navy legend:
“Oh hell, go ahead, England.”
Pendleton’s first Hedgehog attack missed as RO-104 turned. But the second attack at 0834 scored ten detonations, maybe twelve. The explosions merged into one continuous roar. Breaking-up noises followed—metal tearing and bulkheads collapsing. Then, a major underwater explosion occurred three minutes later; the submarine’s batteries had ruptured. Oil and debris surfaced at 1045. That was kill number three. Seventy-two hours, three submarines, and 163 Japanese sailors dead. England still had four more targets ahead.
At 0120 on May 24th, George’s radar detected RO-116 on the surface at a range of 15,000 yards. The submarine dove at 0130, and England established sonar contact at 0150. The pattern was repeating: radar detection, crash dive, sonar tracking, and Hedgehog attack. But RO-116’s commander had changed tactics. He went shallow, staying at 150 feet. Most submarine commanders dove deep to 300 or 400 feet to put maximum water between them and the surface as a cushion against explosions. RO-116’s commander did the opposite, staying shallow and making sharp turns, betting that the Americans would set their firing solutions for deep targets.
He bet wrong. Pendleton’s sonar operator called out the shallow depth, and the Hedgehog firing solution adjusted instantly. The first attack at 0214 resulted in three detonations, maybe five. It was not the massive explosion of previous kills; there was no battery rupture. Instead, there was the sound of 65-pound projectiles punching through the pressure hull at 723 feet per second, creating three-inch holes. At 150 feet depth, seawater enters a submarine at 400 gallons per minute through a three-inch hole.
The breaking-up noises weren’t loud—just the groan of metal under pressure. The submarine settled deeper. More holes meant more water, more weight, and more depth. At 300 feet, the pressure increased and more water flooded in. The temperature inside rose to 200, then 300 degrees. The crew’s lungs seared. Within six minutes, everyone aboard was dead. The submarine continued sinking. Oil and debris surfaced at 0702 after sunrise in a small quantity, though the oil slick expanded over the next 24 hours to several square miles. Fifty-six more Japanese sailors were gone.
That was kill number four. Five days, four submarines. Word reached Admiral Ernest King at the Navy Department in Washington. As the Chief of Naval Operations, he commanded every ship in the United States Navy. King read the action reports: one destroyer escort, four confirmed kills in five days using a weapon most captains didn’t trust. King sent a message to the Third Fleet that was simple and direct:
“There’ll always be an England in the United States Navy.”
The phrase spread through the Pacific Fleet within hours. England was becoming famous, but fame brought attention, and attention brought new orders. On May 25th, Admiral Halsey wanted England pulled from submarine hunting and reassigned to carrier escort duty. She was deemed too valuable to risk. Four kills made her crew experienced, and experienced crews were rare. Halsey wanted to protect the asset.
However, Commander Haynes refused. Three submarines remained on the NA line: RO-105, RO-108, and RO-109. England had killed four in five days, and the mathematics suggested she could kill the remaining three in three more days. To pull her now would leave the mission incomplete and allow Japanese submarines to continue reporting American fleet movements, thus losing the intelligence advantage. Halsey agreed to one more patrol.
At 2303 on May 26th, Rabie gained radar contact on RO-108 at 15,000 yards, 110 nautical miles northeast of Seeadler Harbor. The submarine dove. England gained sonar contact at 1,650 yards. The Japanese commander made the same mistake as RO-116, staying shallow and making radical turns in the belief that the Americans couldn’t track him. But Pendleton’s crew had tracked four submarines before this one; they knew every evasion tactic, every depth change, and every turn pattern. Rabie moved in for the kill but missed with Hedgehog.
Division Commander Haynes gave the order again:
“Go ahead, England.”
At 2323, England commenced the Hedgehog attack on RO-108. Four projectiles hit, maybe six. The explosions came so close together they sounded like one. RO-108 broke apart immediately. There was no slow flooding or gradual sinking; the pressure hull ruptured at multiple points simultaneously. The submarine imploded, and 56 men died in less than three seconds—faster than they could process what was happening.
That was kill number five. Six days, five submarines, and 279 Japanese sailors dead. At Japanese Imperial Navy headquarters in Tokyo, Admiral Toyoda reviewed the patrol reports. Seven submarines had been deployed to the NA line, and five were missing. There were no distress calls and no emergency transmissions—just silence. One submarine every 24 hours. The pattern was obvious. Something was killing his submarines—something fast, accurate, and something the commanders couldn’t evade.
Toyoda issued new orders to the remaining submarines. RO-105 and RO-109 received the transmission on May 27th. The new orders specified a patrol depth of 400 feet minimum and a new surface protocol: no battery recharging unless absolutely necessary. They were also given a new evasion tactic: run silent at first detection with no radical maneuvers, as maneuvers made noise that gave sonar operators better tracking data. The Japanese were learning, but they were learning from dead men’s mistakes.
England, George, and Rabie continued northeast. The NA line had two submarines left somewhere in 3,000 square miles of ocean. The Americans still had the advantage as Fleet Radio Unit Pacific continued intercepting Japanese transmissions. Every radio message gave position data, and every position report revealed patrol patterns. However, the tactical situation was changing. Five kills had depleted England’s Hedgehog ammunition. Each attack fired 24 projectiles, and five successful attacks meant at least 120 projectiles were expended. England carried 240 rounds total, leaving her with 120 remaining—enough for five more attacks, maybe six if the crew was careful.
On May 30th, George detected RO-105 on radar at 2145. The submarine dove immediately, but this time the Japanese commander did something different. He went deep, to 400 feet, and then stopped all engines. There was complete silence—no propeller noise and no machinery vibration for sonar to detect. England established contact at 2,200 yards, but it was a weak, intermittent signal. Sonar operators called it a “knuckle”—a patch of disturbed water that created false returns. The submarine could be anywhere within 200 yards of the signal.
Pendleton faced a choice: fire Hedgehog at a weak contact and likely miss, wasting 24 precious projectiles, or wait for the submarine to move. He chose to wait, giving up the tactical advantage and letting the Japanese commander choose when to run. Four hours passed in silence. Then, at 0230 on May 31st, the signal strengthened. RO-105 was moving. Battery power was running out, and the electric motors needed recharging. The commander had to surface soon or die.
But he had one final, desperate gamble. RO-105’s commander surfaced at 0315 on May 31st, but not where England expected. The submarine had drifted with the current during those four silent hours, moving three miles from her last known position. George’s radar caught her at 13,000 yards, but at the wrong bearing. The hunting group had been searching the wrong grid square. By the time England turned toward the new contact, RO-105 had already crash-dived. The Japanese commander had bought himself 90 seconds of battery charging and diesel engine time—enough to add 10% power to his batteries and run.
England established sonar contact at 0345. RO-105 was running deep and fast at six knots, heading northeast away from the hunting group. This commander was good, perhaps the best they had faced. He had studied the previous attacks and knew that staying deep and running fast made Hedgehog attacks difficult. The problem was, again, mathematics. Hedgehog projectiles sank at 23 feet per second. At 400 feet depth, projectiles took 17 seconds to reach the target. In 17 seconds, a submarine moving at six knots traveled 170 feet. The firing solution required predicting where the submarine would be in 17 seconds.
Pendleton’s first Hedgehog attack at 0405 missed by 200 feet because RO-105 had turned during the descent. A second attack at 0423 missed by 100 feet. It was a better prediction, but still wrong. The submarine was varying her speed between six and four knots, making the math impossible. England had now fired 48 projectiles in this engagement alone. With 72 projectiles remaining, they had only three more chances to kill RO-105 before the ammunition ran out.
Division Commander Haynes watched from George. This engagement was different; the previous five submarines had died quickly within two or three attacks. RO-105 was winning the mathematics game. At 0447, Pendleton’s sonar operator detected a pattern. RO-105 turned every four minutes—30 degrees to port, then 30 degrees to starboard. The pattern was consistent and predictable. The Japanese commander thought he was being random, but humans aren’t random; they fall into patterns. Pendleton adjusted the firing solution, predicted the turn, and led the target by 200 feet.
The third Hedgehog attack was launched at 0508. Twenty-four projectiles splashed into the Pacific and sank into the darkness. Four detonations were heard, maybe five. RO-105’s pressure hull was breached but not destroyed. The submarine continued moving and flooding but was not yet sinking. The Japanese commander began executing emergency procedures: blow ballast tanks, surface, and abandon ship to save the crew.
But England’s fourth attack at 0532 hit with eight detonations. The submarine broke apart, the emergency blow stopped, and the crew never reached the surface. Oil and debris appeared at 0615 after sunrise. That was kill number six. Twelve days, six submarines, and 335 Japanese sailors dead. Admiral Halsey received the report at Third Fleet headquarters. The record was unprecedented, unmatched, and seemingly impossible to believe.
One submarine remained: RO-109. Admiral Halsey issued new orders on June 1st to pull England from submarine hunting immediately. Six kills was enough. The destroyer escort had proven the Hedgehog system beyond any doubt. Every destroyer escort in the Pacific Fleet would now receive updated training, tactics, and firing solutions based on England’s action reports. RO-109 was never found; she had received Toyoda’s warning, abandoned her patrol station, and ran deep and silent toward Truk. She survived the war and surrendered in August 1945.
Her crew only learned about the NA line massacre months later—that six of their sister submarines had been destroyed in 12 days by one ship using a weapon they had never heard of. The Presidential Unit Citation arrived in July, making England one of only three destroyer escorts to receive the honor during the entire war. The citation read:
“For extraordinary heroism in action against enemy Japanese submarines.”
The words didn’t fully capture the accomplishment, but the mathematics did. British forces had a 1.6% success rate with depth charges. Hedgehog attacks before England’s patrol showed a 5% success rate. England, however, achieved a 40% success rate—25 times more effective than depth charges and eight times more effective than the Hedgehog average. By September 1944, the weapon system became standard on every destroyer escort. Training protocols changed across the fleet as sonar operators studied England’s tracking techniques and crews practiced her loading procedures.
In the Atlantic, Hedgehog sank 47 German U-boats by the war’s end with a 17.5% success rate, making it the best anti-submarine weapon of the war. But no ship ever matched England’s 12-day record. Lieutenant Commander Pendleton received the Navy Cross in August. The citation mentioned his tactical brilliance and his crew’s discipline, but it didn’t focus on the mathematics. Pendleton had trusted numbers when other captains trusted tradition. He had calculated while others relied on experience.
England continued escort duty through the summer of 1944 but never found another submarine or fired Hedgehog in combat again. On October 31st, 1944, a kamikaze aircraft hit England off Leyte Gulf. The bomb penetrated the forward engine room, killing 37 crew members and wounding 25 more. The damage was catastrophic, and the Navy decided the ship wasn’t worth the six-month repair cost. She was towed to Manus Island, stripped of equipment, and sold for scrap. In November 1946, the ship that had sunk six submarines in 12 days was cut apart in a salvage yard to become razor blades and tin cans.
The record still stands today; no ship has matched it. Eighty years later, England remains the greatest submarine killer in naval history. Walton Pendleton survived the war, was promoted to commander, and spent his final year hunting submarines in the North Pacific, though he never found any more. He retired in 1961 and died in 1973, buried at Arlington National Cemetery. His gravestone mentions the Navy Cross but not the 12 days that changed naval warfare.
The Navy commissioned a new USS England in 1960, which served until 1994, but when it was decommissioned, the name disappeared from the fleet. The original Hedgehog launcher now sits rusted and forgotten in storage at the National Museum of the United States Navy. Most visitors walk past without noticing the weapon that proved the system worked. Japanese records recovered after the war confirmed the six kills: I-16, RO-106, RO-104, RO-116, RO-108, and RO-105. Each final position matched England’s coordinates exactly.
The Japanese Navy never understood what killed them so fast. Their reports mentioned explosions above and flooding below, but no one survived to describe the forward-throwing mortars. The British developed the Hedgehog, the Americans perfected it, and England proved it. While history remembers the big battleships and carriers, the destroyer escorts were the expendable workhorses. England lasted only two and a half years before being scrapped, but her legacy remains. These men and their mathematical victory deserve to be remembered so they do not disappear into silence.
