During the Cold War, the U.S. Navy studied a concept for a troop-carrying submarine that would have carried an entire U.S. Marine Expeditionary Unit of 2,000 Marines.
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The giant submarine landing craft, or LST, never got off the drawing board. And for good reason. The Navy had plenty of experience with submarine transports. And it wasn’t always good.
Sometime in the 1950s, artist Frank Tinsley drew an impression of a giant submarine LST for Mechanix Illustrated. The magazine “presented” the sketch to the Navy, according to naval historian Norman Polmar.
Tinsely’s submarine LST was 720 feet long and boasted a 124-foot beam. It had room for 2,240 Marines as well as the “amphibious flying platforms” that would land the Marines on the enemy’s shore.
The concept art depicted several submarines disembarking Marines while a sister vessel bombarded beach defenses by way of artillery arrayed on her deck.
Tinsely’s proposal was not a very serious one. For starters, no such “amphibious flying platforms” existed. But the Navy did take seriously other concepts for large, troop-carrying submarines. The fleet, however, didn’t act on them.
The main reason is that surface vessels worked just fine for amphibious assaults. Plus they were cheaper and safer than submarines were. The Navy’s own experiences during World War II and the Korean and Vietnam Wars underscored this truth.
The U.S. fleet during World War II converted its three largest submarines into transports. USS Argonaut, USS Narwhal and USS Nautilus supported amphibious operations on Makin Island in the Pacific as well as Attu, one of the Aleutian islands in Alaska.
In neither case was the submarine assault decisive or necessarily even cost-effective.
Argonaut launched in 1927. She was 358 feet long and displaced 4,100 tons while submerged. She was, by design, a minelayer. But in the hours following Japan’s attack on Pearl Harbor on Dec. 7, 1941, Argonaut made the first-ever attack run of the war by a U.S. submarine when she unsuccessfully approached two Japanese destroyers shelling Midway Island.
An American warplane brought the day to an ignominious end when it mistook Argonaut for an enemy vessel and tried to bomb her.
Argonaut sailed to San Francisco and underwent conversion to a troop transport. Workers removed some of the vessel’s torpedo tubes in order to make room for more berthing. In August 1942 she and Nautilus embarked 222 Marine Raiders and sailed for Makin Island, which housed a strong Japanese garrison and fuel depot.
It was an uncomfortable journey. “For eight days the submarines sailed eastward,” Proceedings, the professional journal of the U.S. Naval Institute, explained in a 1946 article.
“It was hot and cramped in the close quarters,” the article continued. “The temperature of the sea itself was 80 degrees, and although extra air-conditioning units had been installed, the temperature inside the submarines was raised over 90 degrees and the humidity to 85 percent by the sweating bodies of the jam-packed men.”
“All torpedoes had been removed, except for those in the tubes, and bunks had been built in the forward and after torpedo rooms. To fit that many men in, the space between these bunks was so limited that if a man wanted to turn over, he had to slide out of his bed and crawl back up the other side!”
The 85 Japanese defenders on Makin were ready for the Marines and, in a day of furious fighting, killed 30 of them. The Americans ultimately overran the garrison and torched its fuel supplies.
That raid with its mixed results arguably was Argonaut’s greatest success. She sank a Japanese gunboat in early January 1943. A week later three Japanese destroyers depth-charged and shelled Argonaut, sinking her. There were no survivors among her 102 crew.
At 4,000 tons of displacement, Narwhal and Nautilus were somewhat smaller than Argonaut was. Nautilus helped land Raiders on Makin and, in 1942 and ‘43, sank a few small Japanese vessels. In April 1943 she embarked 107 U.S. Army scouts and landed them on Attu five hours ahead of the main American assault on the Japanese-held Aleutians.
Nautilus’ only other major accomplishments during the war were landing scouts on Tarawa in November 1943 and destroying, with gunfire, the submarine USS Darter after Darter ran aground in the Pacific in October 1944.
Sister ship Narwhal helped to shoot down two Japanese planes during the Pearl Harbor attack. She sank some small Japanese freighters in 1942 before joining Nautilus for the attack on Attu.
In their transport roles, Nautilus and Narwhal “were not a critical factor” in the Alaska campaign, Polmar concluded. But the Navy retained transport submarines through the Korean and Vietnam Wars. USS Perch in October 1950 landed 67 British marines behind North Korean lines on a mission to blow up a railroad tunnel.
Perch launched in 1943 and, during World War II, sank two Japanese freighters, landed commandos on Borneo and rescued downed allied pilots. Her raid on North Korea in 1950 was the only allied submarine action of that war.
The unspectacular results of these small-scale amphibious assaults didn’t justify a major expansion of the Navy’s undersea transport capability. Nor would Perch’s missions landing Marine recon troops and Navy demolition specialists during the Vietnam War do so.
The Navy decommissioned its last dedicated transport submarine, USS Grayback, in 1984 following a fatal accident two years earlier that killed five divers.
Today the Navy still uses attacks and cruise-missile submarines to transport small teams of SEALs. But large-scale amphibious raids remain the purview of surface vessels.