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The submarine's story

Humans have long tried to navigate underneath the sea


1620: An alchemist's invention

Cornelis Drebbel is an almost forgotten figure in the early history of science. The Dutch inventor and alchemist spent most of his career in England, with King James I as his patron. He made several contributions to science, but is remembered most often for the first navigable submarine.

Drebbel's sub was a completely enclosed boat, topped with greased leather, and powered by oars with tight leather gaskets around them. Air hoses were held at the surface by floats, while the boat itself was submerged to a depth of 12 to 15 feet. The boat made several trial runs on the Thames River, and James I himself is rumored to have made a trip onboard to demonstrate its safety.

Aside from the mechanical innovations in the submarine, Drebbel might have found a way to isolate oxygen -- a feat usually credited to Joseph Priestly some 150 years later. But Drebbel preferred the mystery and theatricality of a court magician to the rigor of a scientist, and kept few records of his inventions.


September 7, 1776: Bushnell's boat

The Turtle was designed by David Bushnell, who also invented the naval mine. The simple craft held a single person, who drove the horizontal propeller by pedalling and the vertical propeller with a hand crank. An auger on the top of the sub was designed to attach a torpedo to the hull of an enemy ship. There were no ballast tanks; the driver could submerge by flooding the interior, and surface by forcing the water out with a hand pump. The seven-foot-high craft held enough air for 30 minutes under water.

The image shown, an 1875 drawing by Lt. Francis Barber, is the most famous depiction of the Turtle, but contains several inaccuracies.

The Turtle was deployed against the HMS Eagle in New York Harbor during the Revolutionary War. Piloted by Sgt. Ezra Lee, the Turtle managed to approach the Eagle undetected, but a metal plate on the hull thwarted Lee's efforts to attach the torpedo. Exhausted and at risk of being pulled out to sea, Lee jettisoned his torpedo to lighten his boat and divert an approaching patrol. Two subsequent attempts to attack British ships also failed due to the unfriendly currents and tides of the harbor.

The Turtle was lost to history when Bushnell tried to take it to more suitable waters. The British claimed that they sent the Turtle, and the sloop that was carrying it, to the ocean bottom; the Americans claimed they dismantled it and hid it inland.

The image shown was drawn by John Batchelor based on Bushnell's written descriptions of the craft, and corrects the errors in Barber's 1875 drawing; most notably, it depicts two-bladed propellers and no ballast tanks.


July 3, 1801: Fulton's other folly

Nautilus was a remarkable craft designed by a remarkable American engineer -- and one of many of his projects that went nowhere.

Robert Fulton had failed as a painter, and his treatise on canal design barely made a ripple. His submarine design was also underappreciated. The Nautilus used a sail on a retractable mast for surface propulsion, and a hand crank when submerged. It contained enough air to sustain four men and two candles for three hours, and a tank of compressed air was added later.

The French considered the submarine a dishonorable way to wage war, and rejected it. Fulton built the Nautilus with his own money, and tried to sell the British on the idea. The sub succeeded in sinking a ship in tests, but failed on raids against French shipping, leaving the British unimpressed. Fulton was commissioned by the U.S. Congress to build a sub for the U.S. Navy -- an elaborate, 100-man vessel powered by steam -- but he died before it could be completed.

Though his ideas on submarines and canals went nowhere, Fulton secured his place in history by building and operating the Clermont, the first financially viable steamboat.


February 17, 1864: Blockade buster

The Confederate submarine H.L. Hunley was the first to destroy an enemy ship in combat, but it can hardly be called an unqualified success.

The Union Navy had effectively blockaded Southern ports by late 1863, choking off the shipping trade on which the Confederacy depended. Financier Horace Lawson Hunley of Mobile, Alabama, funded the building of submarines in an effort to turn the tide. The first two Confederate subs, the Pioneer and the American Diver, sank before they could attack Union vessels.

The Hunley was the third Confederate effort. After successful trials in Mobile Harbor, the sub was moved to Charleston, South Carolina, one of the ports suffering most from the blockade. On its first mission, the Hunley dove with its hatches still open. Four crew members escaped but the remaining five drowned. The sub was salvaged, and Hunley himself was at the helm for a second set of exercises, which ended in another sinking. Hunley and the other men aboard were killed.

The sub was raised and refurbished yet again. On the evening of February 17, 1864, the Hunley finally engaged a Union sloop, the USS Housatonic. During the mission, the Hunley was spotted. Bullets pinged off the boat's hull as the 22-foot spar torpedo on the sub's bow attached 90 pounds of explosives to the Housatonic's hull. The Hunley then backed away from the ship, detonating the explosives with a cord. The explosion sank the Housatonic, killing five Union sailors. But the Hunley, after signalling to shore that it was returning, never arrived. The location of the wreck remained a mystery until 1995 and why it sank remains a mystery still.

After the second sinking, Confederate Gen. Pierre Beauregard observed that the Hunley was "more dangerous to those who use it than it is to the enemy." On the final scorecard, the Hunley sank three times and claimed 22 Confederate sailors, while sinking one Union ship and killing five Union sailors. The next ship to be sunk by a submarine would be in World War I, some 50 years later.


1869: Vingt Mille Lieues Sous Les Mers

Five years after the Hunley sailed and sank, science fiction writer Jules Verne published his famous account of a madman with a killer submarine. "Twenty Thousand Leagues Under the Sea" followed the power-hungry Captain Nemo and his killer submarine, the Nautilus. The sub, 232 feet long, was powered by electric motors and attacked ships by ramming them.

Verne's fictitious sub firmly planted submarines in the popular imagination, but submarines that could operate at great depth were still decades away. Unlike Verne's Nautilus, few of them would have windows.


April 11, 1900: The Navy comes aboard

The U.S. submarine fleet counts April 14, 1900, as its birthday. On that date, the U.S. Navy bought for $160,000 the Holland VI, which would later be commissioned as the USS Holland. John P. Holland, the boat's builder, was a former schoolteacher who emigrated from Ireland and settled in New Jersey. Holland was fascinated by flight and submarines, and the Holland VI was the result of nearly 25 years of work for him. He is considered the inventor of the modern submarine.

The Holland overcame the greatest weakness of earlier submarines -- human propulsion. It was powered by a 50-horsepower gasoline engine when surfaced, and an electric motor and bank of batteries when submerged. It had a range of 1,000 miles on the surface and 30 miles under water, and featured self-propelled torpedoes.

Holland's company would eventually be bought by his battery supplier. The new firm, the Electric Boat Company, would build most of the U.S. Navy's submarines for decades.


September 5, 1914: The element of surprise

August 1914, the first month of World War I, was not an auspicious beginning for the German U-boat fleet. In the first days of the war, one German sub was sunk, another disappeared, and two more had to turn back with engine problems. None managed to accomplish anything.

Then, on September 5, SM U 21 (in both world wars, German subs had numbers, not names) torpedoed the HMS Pathfinder, a British cruiser, just off the Scottish coast. It sank in minutes. On the 22nd, SM U 9 sank three cruisers, killing 1,460 British soldiers in 75 minutes. The submarine was a credible and deadly instrument of war.

The submarine also played a pivotal political role in the war. On May 15, 1915, the German sub SM U 20 torpedoed and sank the RMS Lusitania, a cruise liner they believed was a troop transport. The attack killed 1,200 people, including 128 Americans. The U.S. government, still officially neutral, protested, and Germany promised not to target civilian shipping.

Germany decreased the scope of its submarine operations in an attempt to keep from drawing the United States into the war. Finally, in February 1917, the German Navy declared unrestricted submarine warfare. In April, the month the U.S. declared war, German subs claimed 860,000 tons of British shipping.

Ultimately, despite the successes of the U-boat fleet, the British navy's blockade of Germany was successful. On October 21, 1918, while armistice talks were pending, the German navy ended unrestricted submarine warfare.


May 24, 1939: Swede the savior

Even in peacetime, submarine duty is not without hazards. The USS Squalus succumbed to tragedy, but was also the setting for an unprecedented technological triumph.

Squalus was conducting test dives when its valves malfunctioned, and it plummeted to the muddy ocean bottom off the coast of New Hampshire. The aft compartments flooded, drowning 26 sailors. But the watertight doors held, and the 33 men in the fore compartments survived. But they were some 250 feet below the surface, in the dark, getting steadily colder, and breathing scarce air.

An urgent search found Squalus, and established communication via the sub's rescue buoy. Its cable snapped, but the rescuers now knew where the sub was and that it still held survivors.

The next morning, the rescue ship Falcon arrived, carrying a team of divers led by Lt. Cmdr. Charles B. "Swede" Momsen. The divers were armed with new rescue techniques and a device called the McCann Rescue Chamber, a deep-submergence diving bell which had never been tested in an actual emergency. The chamber's first three trips went relatively smoothly, bringing 25 sailors aboard the Falcon. The fourth trip was more complicated.

Just before 8 p.m. -- some 35 hours after the sub went down -- the rescue chamber picked up the last group of survivors, including the sub's commander, Lt. Oliver F. Naquin. The chamber's guiding cable jammed while it was still 160 feet below the water's surface, and remained stuck for four hours while divers attempted repairs. Finally, just after midnight on May 25, the last survivors of Squalus came aboard the Falcon.

The Squalus would be the site of another dramatic effort in the summer of 1939, when it was salvaged from the ocean bottom. It was then repaired and recommissioned as the Sailfish, and credited with sinking seven enemy ships in World War II.


1940: Das Wolfpack

In World War II, the U-boat was again a crucial weapon for the Germans. Early in the war, German U-boats had a great deal of success attacking one ship at a time, but by 1941, merchant ships were organized into convoys and better escort craft were becoming available. The German response was the wolfpack.

The wolfpack was the British-coined name for the coordinated group attacks developed by Adm. Karl Doenitz. The U-boats formed patrol lines, and searched for convoys. One sub would be designated to shadow the convoy, and would signal command. The other boats in the pack would then surround the convoy, strike at the same time, and escape in the chaos.

The U-boats were deadly. The wolfpacks devastated Allied shipping, destroying cargo ships faster than the Allies could build them. Even on the "safe" side of the Atlantic, a German offensive off the U.S. East Coast sank some 397 ships in its first six months. American ships adapted the convoy tactics that had helped the British, and the German subs returned to the North Atlantic in July 1942.

That year was the peak of the U-boats' effectiveness. Allied technology would begin to turn the tide in 1943.


1940-1943: Hunting the hunters

While German wolfpacks ravaged Allied shipping, scientists and engineers on both sides of the Atlantic worked frantically to develop new ways to combat the U-boat.

Perhaps the most pivotal advances, and the best-kept secrets, came from Project Ultra at England's Bletchley Park. Naval codebreakers cracked the formidable German Enigma codes, which the Germans believed to be unbreakable. Aided by Britain's most gifted mathematicians and machines called "bombes" -- an early mechanical computer -- Ultra was deciphering German communications within 24 hours in the latter years of the war.

Another advance, also unknown to the Germans, was the High Frequency Direction Finder (HF/DF, or "huff duff"). The HF/DF was a system of shore-based and ship-based antennas that allowed the Allies to pinpoint a U-boat using the sub's own radio signal. Because wolfpack tactics depended heavily on coordinating attacks by radio, HF/DF allowed the convoys to evade the shadowing sub while the escort ships, using improved radar and sonar systems, zeroed in and attacked.

Those attacks most often came in the form of depth charges, explosives set to explode at a particular depth. Their explosions looked impressive and rattled submarines, but were not terribly effective; one U-boat survived 678 depth charges and escaped. They were effective, however, at forcing subs to lower depths and interrupting a planned attack on the convoy.

A more effective weapon was the "hedgehog," deployed in 1943. Hedgehogs fired an array of explosives just in front of the sub, and they detonated when the sub's hull struck them. The Allies also developed acoustically-guided torpedoes and air-launched armor-piercing rockets that took a heavy toll on the U-boats.

Most of the U-boats sunk were done in by surface ships (264), aircraft (250) or a combination of both (37). Allied subs sank only 19 U-boats. In all, the U-boats claimed 3,500 merchant ships, but at great cost as 784 U-boats went to the bottom. Out of nearly 41,000 men recruited for the Unterseebootwaffe, some 28,000 died and 5,000 were taken prisoner.
December 7, 1941: Subs come to the forefront

The surprise Japanese attack on the U.S. naval base at Pearl Harbor, Hawaii, was a crippling blow against the Pacific fleet. American submarines were spared in the attack, and Adm. Chester W. Nimitz, named commander of the Pacific fleet weeks later, said their role was crucial.

"When I assumed command of the Pacific Fleet on 31 December 1941, our submarines were already operating against the enemy, the only units of the Fleet that could come to grips with the Japanese for months to come," Nimitz said. "It is to the everlasting honor and glory of our submarine personnel that they never failed us in our days of great peril."

Japan, a small island nation with scarce natural resources, relies on imported raw materials, and interruption of merchant shipping was a daunting blow to its military and industrial output. By the spring of 1945, aluminum was in such scarce supply that Japan was planning to build airplanes entirely out of wood.

The submarine was a strikingly effective means of economic warfare -- Japan's anti-sub efforts and shipping losses totalled some 42 times what the U.S. spent on its submarine force. But the human costs were high as submariners made up only 1.6 percent of the U.S. Navy, but 22 percent of its casualties.

American efforts, as with Allied ships in the Atlantic, were boosted by aggressive and effective code-breaking and intelligence efforts.


September 2, 1944: Saving Lt. Bush

As the war steamed from island to island across the Pacific, the Pacific submarine command considered the difficult task of how to rescue downed airmen in vast seas, often under enemy control. The solution was lifeguard submarines, one of the less-heralded missions of the World War II submarine fleet.

In October 1943, the USS Skate rescued a naval aviator from the waters off Wake Island. It would be the first of six rescues in a four-day patrol for the Skate, and of 520 aviators rescued by 87 boats for the Submarine Lifeguard League.

One of those aviators was Navy Lt. j.g. George Bush, a 20-year-old pilot (and future president of the U.S.) who bailed out of his burning Avenger dive bomber near the island of ChiChi Jima. Bush was rescued by the USS Finback, which was just beginning its patrol, and he remained aboard the boat for nearly a month, while it sunk Japanese freighters and survived depth charge attacks.

The champion of the Lifeguard League was the USS Tigrone, which rescued 31 airmen. The sub also fired the last shots of the war, shelling a radar site on Tokyo Bay. Tigrone was submerged when the ceasefire took effect on August 14, 1945, and didn't receive word until later in the day. Tigrone was the last of the World War II subs in active service, and was decommissioned in 1975.


September 30, 1954: 'Underway on nuclear power'

For nearly half a century, the vast majority of submarines were diesel-electric models. Their range was limited by the amounts of fuel they could carry, they could remain submerged only as long as battery power lasted, and their electric motors could operate only at slow speeds. The end of World War II ushered in the nuclear age, shattering logistical limitations and opening new strategic roles for submarines.

Engineers from the Navy and the Atomic Energy Commission began work on a nuclear reactor plant to operate a submarine in 1951. The Nautilus -- the sixth U.S. Navy vessel to bear that name, and the namesake of Robert Fulton's sub and Jules Verne's fictitious one -- was launched in January 1954, and commissioned on September 30. On January 17, 1955, the Nautilus set sail as Cmdr. Eugene Wilkinson signaled the message "underway on nuclear power."

Nuclear power quickly became the primary form of propulsion for U.S. subs. The reactor does not require air, and eliminates the reliance on batteries -- coupled with air-scrubbing machinery, nuclear power enables a submarine to remain submerged for extended periods. Modern nuclear subs will run out of food before they run out of power or air.

Nautilus logged nearly half a million miles at sea, including a 1958 voyage underneath the North Pole. Decommissioned in 1980, Nautilus was named a national historic landmark, and is now a museum in Groton, Connecticut, where it was built.


Cold War: The 'silent service'

The Cold War years were marked by secret operations and the threat of the ultimate weapon, nuclear warfare. Submarines played a crucial role in both.

The USS George Washington (pictured) was the first ballistic missile nuclear submarine, launched in 1959. Missile subs offered a key deterrent for both sides -- even if a first strike crippled an enemy's land-based missiles, submerged missiles from carefully hidden submarines would preserve the ability to retaliate.

Nuclear-powered "fast-attack" or "hunter-killer" subs tracked and targeted the missile subs, nicknamed "boomers," throughout the Cold War. In a high-stakes game of cat and mouse, submarines tried to detect each other while remaining invisible (or, more accurately, inaudible) themselves. Subs were also fitted with facilities to get personnel -- usually Navy Seals -- into and out of any location in secret.

After the Cold War's end, the role of submarines shifted; the Virginia class, a new submarine in development, is designed to launch cruise missiles and deploy commandos in secret. Ballistic missile submarines still patrol the world's oceans.


March 17, 1959: The first 'ice run'

In August 1958, the USS Skate became the second vessel to pass under the North Pole, following almost literally in Nautilus' wake. The following March -- the time of year when the Arctic ice pack is at its thickest -- the Skate took polar exploration a step further.

In a 12-day, 3,000-mile voyage, the Skate forced its way through the ice 10 times. At the North Pole itself, the boat surfaced and scattered the ashes of Sir Hubert Wilkins, a famed polar explorer. The boat earned a unit commendation and a bronze star for its polar missions.

After its polar expeditions, Skate served in both the Atlantic and Pacific fleets until it was decommissioned in 1986.
June 5, 1964: The little sub that could

While both sides in the Cold War pursued submarines to fight or deter a war, some scientists saw vast potential in the scientific use of submarines. In 1960, Charles Momsen, the leader of the Squalus rescue, was the head of the Office of Naval Research (ONR). He offered ONR funds for researchers to rent submersibles for scientific use. The Woods Hole Oceanographic Institute could not find a suitable sub available for rent, so it decided to build one.

General Mills won the contract with a $472,517 bid. The sub was named Alvin, partly after project originator Allyn Vine, and partly after the popular cartoon chipmunk. Alvin was commissioned on June 5, 1964, and, after a series of upgrades, is still in use -- and still state of the art -- today.

In more than 3,500 dives, Alvin has been used to retrieve a hydrogen bomb lost in a plane crash off Palomares, Spain; to study previously inaccessible sections of the sea bottom; to shoot underwater IMAX films; and to discover and to document longlost shipwrecks, including the RMS Titanic.

Alvin houses a crew of two or three in a sphere at the front, can operate an array of video and still cameras and a robot arm, and can retrieve objects from the ocean bottom. The submersible is a mere 23 feet long, but is certified to operate at depths of more than 14,000 feet -- in lab tests, a duplicate sphere survived the equivalent of more than 22,000 feet without failing.


1974: Operation Jennifer

A reclusive and eccentric billionaire builds a $200 million ship in a risky scheme to mine minerals from the ocean bottom. It was a great story -- too good to be true, in fact.

When Howard Hughes and Global Marine built the Glomar Explorer under the auspices of the Deep Ocean Mining Project, it seemed like another expensive whim. In fact, Hughes was providing cover for American intelligence. The real objective was not manganese nodules, but a Soviet ballistic missile submarine that sank in the Pacific in 1968.

In the summer of 1974, the Glomar Explorer found the sub. Strong cranes hauled the sub's hull into the ship's "moon well," an open vault in the middle. That the Explorer recovered at least part of the sub is well documented; what the U.S. got is still a matter of debate. By some accounts, the entire sub was recovered, scoured and returned to the ocean. According to other records, the sub broke in half and most of it was lost. The U.S. may or may not have recovered nuclear missiles, nuclear torpedoes and code books. Many of the records of the mission remain classified.

American sailors definitely found the bodies of six members of the sub's crew. In a surreal event, those Soviet sailors were buried at sea with full military honors, presided over by a U.S. Navy chaplain. That ceremony remained a secret until 1992, when then-CIA chief Robert Gates presented a videotape of the ceremony to Moscow.


May 6, 1986: Rendezvous at 90° North

The Cold War earned its name most literally in the Arctic. Submarine operations under the ice were a boon to science, but they also served a military purpose -- the shortest route between North America and the Soviet Union ran underneath the pole.

In 1986, U.S. subs rendezvoused under the ice and fired practice torpedoes at each other to measure their performance in the Arctic. The high point of the exercise came on May 6, when the USS Hawkbill, the USS Archerfish and the USS Ray surfaced within a few hundred yards of each other at the North Pole.


January 19, 1991: Subs wage war in the desert

Operation Desert Storm was the first military conflict of the post-Cold War era. Some 700,000 Allied troops faced off against 300,000 Iraqis in one of the most lopsided military engagements in recent memory.

The U.S deployed many of its high-tech weapons against Iraq, including cruise missiles, which fly low and hug the terrain using digital maps and satellite guidance. The first submarine-launched cruise missile was fired by the USS Louisville in the Red Sea.