The Last Act of the USS O-9 Submarine Tragedy

By the spring of 1941, the world was already at war. Hitler’s armies had swept across Europe, the Luftwaffe had bombed London, and U-boats prowled the North Atlantic. The United States was not yet formally in the fight, but the Navy was preparing for the possibility that it soon would be. Shipyards were running at full tilt, new battleships, carriers, and submarines sliding into the water. But building a modern fleet took time, and time was the one resource that seemed in shortest supply.

That is how a relic like USS O-9 (SS-70) found herself back in service. She belonged to the O-class, a group of coastal defense submarines hastily built during the First World War. Commissioned in 1918, O-9 was already considered obsolete by the mid-1920s. She had been decommissioned once before, in 1931, and stored in mothballs. The Navy had moved on to more capable designs — the big fleet boats that could roam the Pacific and chase down enemies across oceans. By comparison, the O-boats were stubby, cramped, and mechanically temperamental.

Yet in 1941, the Navy needed every steel hull it could find. The O-class may have been outdated, but they could still serve a role. They were recommissioned not as front-line warships, but as training platforms. Young officers and crews needed to learn the fundamentals of submarine operations before moving on to the larger and more complex boats. That meant diving, surfacing, handling engines, living inside steel tubes — all the practical lessons that would matter when they transferred to the new Gato and Tambor-class submarines entering the fleet.

So O-9 was dusted off and recommissioned at Portsmouth Navy Yard on April 14, 1941. She looked every bit her age, her design a throwback to the early days of undersea warfare. Her hull length was just 172 feet, her beam barely 18 feet across. Below the waterline, she carried two tiny torpedo rooms. Crew accommodations were primitive, the air foul when submerged, the space so limited that sailors joked you could smell what your shipmate had for breakfast all day long. But she was seaworthy, and she was needed.

By June 1941, O-9 was back at work off Portsmouth, assigned alongside two of her sisters, O-6 and O-10. They were there to run practice dives, teaching a new generation of submariners the skills of the Silent Service. No one thought of them as war-ready vessels. They were more like battered old schoolhouses, useful for teaching lessons but never meant to fight again.

Yet on the morning of June 20, 1941, O-9 would remind the Navy in the harshest possible way that submarines — even in training — carried risk. Within hours, she would vanish beneath the Atlantic, taking all 33 men aboard with her. And by September 20, 1941, her final resting place would be found on the seafloor, too deep for rescue, a steel tomb holding the men who went down inside her.

The O-class submarines were born in urgency. When America entered the First World War in 1917, the German U-boat threat was strangling Allied shipping in the Atlantic. The U.S. Navy needed submarines quickly, and Congress authorized a rush of new construction. Designers produced a class of small coastal defense boats, intended not to roam far from home waters but to patrol harbors, guard shipping lanes, and train crews. These were the O-boats.

They were never glamorous. At just over 500 tons submerged, they were dwarfed by the German U-cruisers that could cross the Atlantic. Their test depth was shallow, about 200 feet, and their systems were simple. Each carried four torpedo tubes in the bow and a single 3-inch deck gun. Their engines were notoriously temperamental, with diesel fumes choking the crews and batteries that gave off toxic gases when stressed. But they could be built quickly, and quickly was what the Navy needed in 1917.

USS O-9 was laid down in Quincy, Massachusetts, in 1917 and commissioned in July 1918, too late to see combat. Like her sisters, she was outdated almost the moment she entered the fleet. Naval technology was advancing rapidly. By the mid-1920s, the Navy had already moved on to the newer V-boats, which were bigger, more reliable, and better armed. The O-class found themselves relegated to secondary duties: training midshipmen at the Naval Academy, running drills out of New London, and patrolling close to the American coast.

By the 1930s, their age was showing. The Navy retired most of them by 1931, sending them to mothballs or scrapping them outright. O-9 herself was decommissioned in June of that year, thought to be finished for good.

Yet history has a way of pulling old warhorses back onto the stage. When war clouds gathered again in the late 1930s, the Navy realized it had a looming shortage of submarines. The new fleet boats — the Tambors, Gar, Gato, and Balao classes — were on the drawing boards, but they would not be available in large numbers until 1942 and beyond. The Navy still needed to train crews, and there were only so many modern boats available. So the decision was made to bring several of the O-class out of retirement.

It was a desperate kind of logic. These old boats could not fight against Japan or Germany. They were too slow, too shallow-diving, and too prone to mechanical failures. But they could still serve as classrooms of steel. Young officers could learn how to run engines, handle ballast tanks, and live inside a submarine’s pressure hull. And if something went wrong, the Navy told itself, these lessons would be lost only in training, not in combat.

It was a cruel irony. By 1941, the O-boats were already regarded as unsafe. Even their crews joked about serving on them. Some sailors called them “pigboats,” a nickname that stuck to the entire submarine force in those years, but with particular sting for the O-class. To many submariners, an assignment to an O-boat was not a mark of honor but of bad luck. Yet the Navy needed them, so they were recommissioned and put back to sea.

O-9, recommissioned in April 1941, was one of those brought back. She was already twenty-three years old, a relic of a past war. And it was precisely that age, that obsolescence, that would matter most when she was ordered to perform a deep dive off Portsmouth only two months later.

Life aboard any submarine in 1941 was not easy, but on the old O-class it was especially rough. The boats were designed for short coastal patrols, not long voyages across oceans, and that meant comfort had been sacrificed from the start. O-9 was just 172 feet long and 18 feet wide at her beam. Inside, space was measured in inches. A crew of 33 men had to live, eat, and work in that narrow steel tube, crammed around engines, batteries, torpedoes, and piping. Privacy did not exist.

The smell was the first thing anyone remembered. Diesel oil soaked the decks, and the heavy fumes clung to the air. Battery acid gave off a sour bite, mixed with the tang of sweat and the stink of unwashed clothes. Ventilation was poor, so cooking smells hung for days. A mess of beans or fish might as well have been painted into the steel. Sailors joked grimly that the O-boats didn’t need to hide — the enemy could smell them from a mile off.

Sleeping arrangements were tight. Hammocks and bunks were wedged wherever space could be found, sometimes strung above torpedoes or tucked between pipes. A man could reach out in the dark and touch his bunkmate’s elbow without even stretching. Sleep was light and often broken, punctuated by the throb of engines or the call of a watch change. There was never enough fresh air. When submerged, the atmosphere quickly grew heavy, every breath tasting like a mix of oil and carbon dioxide.

Meals were simple. There was a tiny galley, but storage was minimal. Canned goods, beans, coffee, and bread made up the bulk of the diet. Iceboxes kept perishables for only a short time. Men ate elbow-to-elbow, perched on benches so narrow they could barely hold a plate. Coffee was always brewing, strong and bitter, because fatigue was constant.

Discipline was strict, but life aboard a submarine also bred camaraderie. In such tight quarters, men had to rely on each other. A mechanic working the diesels had to trust that the electrician was keeping the batteries steady. A helmsman had to trust the diving officer to balance ballast tanks correctly. There was no room for passengers. Every man had a job, and if he failed, all hands were at risk.

For the young sailors assigned to O-9 in 1941, this was their introduction to the submarine service. They knew the boat was old, and they knew she was not meant for glory at sea. But she was their boat, and for many it was their first taste of what life would be like under the ocean. The close quarters bred humor as well as tension. Nicknames flew, pranks were common, and shared misery forged bonds that could last a lifetime.

Still, beneath the joking, there was unease. Everyone aboard knew O-9 was an antique. Weld seams groaned under stress, engines broke down, leaks were constant. To the veterans, she felt fragile. To the new hands, she was simply all they knew. On the morning of June 20, 1941, as they prepared for their scheduled deep dive, those 33 men carried the ordinary feelings of sailors — weariness, duty, a hint of nerves, and the expectation that this was just another drill in a long line of drills. None of them could know that by mid-morning, O-9 would be gone, and the cramped steel tube they called home would become their grave.

The morning of June 20, 1941, broke clear and calm off the coast of New Hampshire. The Navy had ordered three O-class boats — O-6, O-9, and O-10 — out for scheduled test dives. They were to conduct deep submergence trials, pushing the old hulls toward the edge of their limits. To the officers on shore, it was a routine training evolution. To the men aboard the submarines, it was just another day of following orders.

The three boats steamed out of Portsmouth together. Their assigned diving area lay about fifteen miles off the coast, in water known to be more than four hundred feet deep. That was well beyond the O-boats’ official test depth of 212 feet. It was dangerous territory, but the Navy wanted to know how much punishment these hulls could take.

0830 hours — O-6 made her dive first. She submerged cleanly, her deck awash, conning tower slipping beneath the waves. After a period below, she surfaced again, engines roaring to life. The reports from her crew were routine. No problems.

0845 hours — O-10 followed. She, too, descended beneath the waves. Time passed, the sea quiet but for the slap of swells against the watching escort vessel. At last, O-10 surfaced. Another routine dive complete.

Now it was O-9’s turn.

0837 hours — O-9 signaled that she was beginning her dive. The men on the other boats would have watched her slip beneath the water, the last glimpse of her conning tower vanishing into the Atlantic. She was expected to surface again within an hour.

But the hour passed. Then another.

1000 hours — O-9 was due on the surface. The horizon remained empty. O-6 and O-10 waited, engines idling, eyes straining across the waves. There was no sign of her.

By mid-morning, tension turned to alarm. Radios crackled, signals sent to shore. O-9 was overdue, and there was no word from her. A search began at once.

By noon, rescue craft were already mobilizing. At Portsmouth, word spread quickly: O-9 had failed to surface. Families of the crew, yard workers, and other sailors gathered, waiting for news. The Navy’s worst fear was beginning to unfold — that the old submarine had gone too deep, and the sea had claimed her.

By that afternoon, oil slicks were spotted in the dive area. Bubbles rose to the surface, evidence of something broken far below. The crews of O-6 and O-10, men who had watched their sister boat vanish just hours before, knew in their hearts that O-9 was gone.

But the Navy was not ready to give up. Even as the hours stretched into night, preparations were underway for an all-out rescue attempt. Divers and salvage ships were ordered to the scene. If there was any chance at all, they would have to act fast. For the men entombed below, time was already running out.

When O-9 failed to surface, the Navy moved with urgency. Every minute mattered. A stricken submarine could hold its air for only so long, and no one knew if the men inside were alive, pounding on the hull, waiting to be saved. The call went out to the USS Falcon (ASR-2), the Navy’s primary submarine rescue vessel, along with other salvage ships and diving teams from New London.

By dawn on June 21, the scene fifteen miles off Portsmouth was a hive of desperate activity. Surface ships patrolled the waters, dropping marker buoys over oil slicks that bubbled up intermittently. The Falcon’s crew rigged their gear, preparing for dives into waters deeper than they had ever attempted before.

The conditions were against them from the start. Navy divers in 1941 trained for depths of about 200 to 300 feet. O-9 lay at nearly 450 feet, far below what the equipment of the time could safely handle. The rescue chambers developed after the Squalus disaster in 1939 were useless at that depth. The Falcon’s men knew it, but they tried anyway.

Teams of divers went over the side, weighted down with heavy suits and helmets. Each descent was a battle against crushing pressure and darkness. At 300 feet, even experienced men struggled to stay conscious, their lungs and blood squeezed by the Atlantic’s weight. One diver reported that his chest felt as if an iron band had clamped around it. Beyond that depth, their bodies simply could not endure.

Still, they pressed down, searching for any sign of life. They tapped with hammers, listening for a reply from the hull below. Nothing answered. They tried again and again, until exhaustion and the limits of physics forced them back.

For three days the rescue effort continued. Ships swept the seabed with grapnels, hoping to snag wreckage or cables that might lead them to the boat. Oil continued to seep to the surface, grim confirmation that something was torn open below. But no messages, no air bubbles, no tapping hands came back from O-9.

On June 22, after seventy-two hours of searching, the Navy called off the rescue. Admiral Harold Stark, Chief of Naval Operations, issued the order to cease efforts. There was no chance of survival. Thirty-three men were gone, entombed in a steel coffin far beneath the waves.

At Portsmouth, families who had clung to hope were told the truth. O-9 was lost. The Navy held memorial services, and a roll call of the dead was read. Bagpipes and bugles sounded across the yard, flags drooped at half-mast, and tears fell freely among wives, children, and shipmates.

The sea had taken O-9, and for the moment, it had hidden her well. The precise location of the wreck remained uncertain. Only the oil slicks and the silent expanse of ocean marked where she had gone down. But the Navy was not finished. It would be three months later, on September 20, 1941, before they found her exact resting place.

When the rescue was abandoned on June 22, 1941, the official announcement carried a weight that crushed families and shipmates alike. Thirty-three men were gone. They had been alive on the morning of June 20, preparing for a routine dive, and now they were names on a casualty list.

At Portsmouth Navy Yard, a memorial service was held. The flag hung at half-mast, and the Navy band played the slow, solemn notes of “Eternal Father, Strong to Save,” the hymn of the sea. A chaplain read prayers over the gathered families, their faces streaked with grief. Officers and yard workers stood in silence as the names of the crew were read aloud.

There was Lieutenant Commander Howard J. Abbott, O-9’s commanding officer. He had joined the Navy in the 1920s, a veteran submariner, and like many of his men, he had surely understood that his boat was too old, too fragile for such trials. But duty bound him, and he had gone down with her.

There were the junior officers, eager for experience. There were machinist’s mates, electricians, torpedomen, cooks, and seamen. Men in their thirties with wives and children waiting at home, and men barely out of boyhood, still learning the craft of the Silent Service. Thirty-three individuals, each with a story, now joined together in tragedy.

The Navy read their names as one body, one crew. Each name was followed by a toll of the bell, each strike echoing across the yard. The sound carried out to the river, out to the sea, where O-9 lay hidden in the depths.

The service ended with a rifle salute, three volleys cracking across the water. Then taps sounded, the notes trailing away into silence. For the families, it was the last official farewell. For the Navy, it was a reminder of the risks carried even in training. For the submariners who would fight in the war to come, it was a lesson written in lives: the ocean never forgives mistakes, and submarines give no margin for error.

In time, O-9’s name was etched into the roll of lost boats, honored as “on eternal patrol.” But in those first weeks after the disaster, she remained missing. The Navy knew she lay beneath the swells, but her exact position had not yet been fixed. The wreck was still out there in the Atlantic, a tomb unmarked. It was not until September 20, 1941, that they would find her again, and know precisely where the men of O-9 would rest forever.

For three long months after O-9’s disappearance, the Atlantic held her secret. The Navy knew she was down, but not exactly where. The oil slicks had drifted, the bubbles of escaping air had ceased. What remained was silence, and the uncertainty gnawed at the service. Families wanted closure. Sailors wanted to know where their shipmates had gone. And the Navy needed to mark the grave.

On September 20, 1941, the search paid off. Salvage vessels, working with sonar and sweep gear, fixed O-9’s resting place. She lay about fifteen miles off Portsmouth, far deeper than her hull had ever been designed to go. The sea floor was more than four hundred feet down, a crushing world where steel itself had buckled.

Divers went down as far as they dared, pushing to the edge of human endurance. Even with weighted suits and heavy helmets, the pressure was immense. At 300 feet, their bodies screamed for relief, their chests compressed, their blood struggling against the weight of the Atlantic. They could not reach the wreck itself, but they saw enough. Twisted fragments, dark shapes below, and the unmistakable sheen of oil seeping upward from the depths.

There was no doubt. O-9 was there. The Navy charted the location, officially recording the wreck site. There would be no salvage attempt. The depth was beyond 1941 technology, and even if it had not been, the damage made recovery impossible. The wreck was declared a permanent tomb.

Back at Portsmouth, a second memorial was held. Officers spoke of bravery and sacrifice. Chaplains reminded families that their sons and husbands rested together, bound as a crew, watched over by the sea they had served. A buoy was placed to mark the spot, a silent sentinel above the grave.

The discovery did not bring the men home, but it gave them a place in the world, a known position where shipmates could point and say: “There. That’s where they are. That’s where O-9 keeps her watch.” It was cold comfort, but it was something.

And from that day, September 20, 1941, O-9 ceased to be simply a lost boat. She became a remembered one. Her coordinates entered into the Navy’s rolls, her name added to the list of submarines on eternal patrol, her crew memorialized each year by the men of the Silent Service.

The loss of O-9 was not the first submarine tragedy for the U.S. Navy, and it would not be the last. Only two years earlier, in 1939, the brand-new submarine Squalus had gone down off Portsmouth as well. That disaster had spurred the invention of the McCann Rescue Chamber and had proven that submariners could be saved when a boat sank in shallow water. But O-9 lay twice as deep, beyond the reach of divers, rescue chambers, and technology of the time. Her loss was a harsh reminder of the unforgiving physics of the sea.

In practical terms, O-9’s destruction underscored what submariners already knew: older boats were dangerous, especially when pushed beyond their limits. The O-class had served its purpose in World War I, but by 1941 it was a relic. After O-9’s loss, the Navy looked more critically at how such vessels were being used. While other O-boats continued to train men into the early years of the Second World War, the urgency to retire them grew. Better to risk them in shallow drills than in deep-water tests that their hulls could not endure.

For the men of the submarine service, O-9 became part of a roll call they knew too well — the boats “on eternal patrol.” Her crew’s names joined the long list of those who never returned. Every June, at Portsmouth and at submarine veteran gatherings around the country, their sacrifice is remembered. A bell tolls for each man, and the words are spoken that carry weight to this day: “They are still on patrol.”

The wreck itself remained undisturbed. The Navy never attempted salvage, and rightly so. She was left where she lay, 450 feet down, the steel twisted and crushed, but her identity certain. In later years, modern divers equipped with far better technology would venture down, confirming her shape on the seabed, still holding her crew. They reported a silent, broken hulk, coated in marine growth, but unmistakably O-9. The ocean had kept her.

Today, O-9’s story stands as both a caution and a commemoration. It tells us that submarines, no matter their purpose, are unforgiving machines, demanding respect. It also tells us of thirty-three men who did their duty, knowing the risks, and who paid the price when steel and sea conspired against them. They did not die in combat, but their sacrifice carried the same weight. They were sailors, submariners, and brothers in arms.

The Navy, and the submariners who followed, never forgot. When veterans gather, when families lay wreaths, when the hymn of the sea is sung, O-9’s name is spoken. Her grave is marked not by a headstone, but by the Atlantic swells fifteen miles off Portsmouth. Beneath them, in the cold darkness, thirty-three men stand their final watch, guardians of a legacy written in silence.

On June 20, 1941, O-9 slipped beneath the waves and never returned. On September 20, 1941, the Navy found her again. And in the years since, her story has endured — a reminder of the risks of the Silent Service, and of the men who gave their lives before America had even entered the Second World War.