Liberty ships: World War II’s beasts of burden

The immense fleet of Liberty ships built during World War II is now all but forgotten except among a few history buffs and the few left who sailed them. But they understand the crucial role played by these ugly ducklings.

This acrylic painting, entitled “For Those in Peril on the Sea,” depicts a Liberty ship in a convoy on the North Atlantic during World War II. It was painted by Brian Hope, a Maryland pilot and the former chairman of Project Liberty Ship, the group that restored and maintains SS John W. Brown.

When they were built, the need for vessels to transport war materiel was so urgent that corners had to be cut in their design. The underpowered Libertys were very slow. They cruised at only 11 knots, making them easy targets for both German and Japanese submarine and air attacks. But without the Liberty ships, the Allies could not have won the war.

Reviving an industry

After World War I, the U.S. shipbuilding industry went into a steep decline. For the 15 years between 1922 and 1937, a total of two dry cargo ships were built in the United States, along with a few tankers.

By 1936, Congress passed a Merchant Marine Act creating the U.S. Maritime Commission. It was in charge of creating a new and efficient U.S. merchant fleet. The purpose was to develop a fleet for both domestic and foreign oceanic commerce. If needed, this fleet would also serve the national defense.

Shipbuilding had reached such a decline by the time the commission was established that there were only 10 shipyards in the entire country capable of building oceangoing ships over 400 feet long.

In 1937, a 10-year construction program started to replace the elderly merchant fleet. It called for building 50 ships a year. The replacement fleet was to consist of fast tankers and three types of fast cargo ships. While the basic hulls and power plants were standardized, much of the equipment for cargo handling and crew accommodations were varied to fit the needs of different shipowners and operators.

Shortly before the war in Europe started in 1939, the original schedule was doubled to 100 ships a year, and then doubled again in 1940 to 200 ships a year. By that time, the 10 operating shipyards of 1936 had grown to 19. The ships being built under this program were excellent vessels and comparatively fast. In 1940 one of the new ships made a trans-Atlantic crossing averaging a speed of 17 knots. During that same year the commission completed its first all-welded vessel. This technique enabled shipbuilders to assemble vessels much more rapidly than by riveting. Welding also reduced the weight of a ship by about 600 tons.

In 1939, war broke out in Europe. By 1940, the Nazis had swept through western and central Europe, leaving Britain alone. Germany’s U-boats were sinking ships faster than the British could build them. They sank 150 ships in the first nine months of the war.

In September of 1940, a representative of J.L. Thompson, a major British shipbuilder, came to the United States to order ships here. The company brought plans for a freighter based on a Thompson-designed prototype built in 1939: a 10,000-ton vessel driven by a 2,500-hp engine cruising at 11 knots.

In New York, the British group met the chairman of the U.S. Maritime Commission, Adm. E.S. Land. Understanding the awkward position Britain was in, Land saw no point building these “simple, slow” ships. He wanted the Brits to buy 60 of the commission’s much faster C-ships. This certainly would have been an excellent idea, except that no yards were available to build them. They’d have to be built in new shipyards or not at all.

The solution was new yards built by a partnership between Todd Shipyards Inc. and a consortium of companies owned by Henry J. Kaiser.

This appeared to be an ideal combination, since Todd was a well-established shipbuilding firm, and Kaiser was equally well-established in heavy construction.

Although hull construction was soon proceeding well in these new yards, the high-powered engines needed to drive the new C-ships were complicated. Adequate numbers of these engines simply were not going to be available quickly enough. By 1941, it was obvious that these faster, more complicated vessels would have to wait. What was needed immediately was quantity rather than quality.

Clearly, a new design would require time-consuming development and testing, taking time that neither the British nor we had. Land finally, but reluctantly, decided to adopt the already available “slow” British design. The triple-expansion steam engine was also based on a British design that dated to about 1900.

Building the Liberty fleet

No mention was ever made to those of us who sailed on them, or to those who built them, or to the public, that the ship was based on a British design. However, the adaptation of this design to mass production was entirely an American accomplishment.

Probably the most important change was the method of assembly. At the time this program started, riveting was still the standard method for building ships. However, welding had been tried in the United States and found to save considerable weight and to allow for much faster assembly.

Welding sped up the shipbuilding process tremendously. In 1919, a 50-way shipyard built a total of 69 riveted ships in a year. In 1943, a 12-way shipyard launched 205 welded ships.


The move to welding required a number of alterations in the designs. The original high standards of the U.S. Maritime Commission for the C-ships were reduced and reduced again, with the intention of simplifying these vessels for speedier and easier construction. One major change was to provide quarters for the entire crew in a single midship deckhouse. The Maritime Commission considered this arrangement safer for open-ocean passages, and it allowed for savings in piping and heating.

The normal crew consisted of 45, plus a Navy gun crew of up to 36. The ship’s armament normally consisted of a 3-inch antiaircraft gun mounted on the bow, a 5-inch gun on the stern and four 20-mm machine guns mounted on the deck above the bridge.

After the design modifications were completed, the general specifications for the hundreds of cargo ships that were finally built were established:

• carrying capacity, 10,500 dwt

• length overall, 441 feet 7 inches

• beam, 56 feet 10 inches

• loaded draft, 27 feet 7 inches

• cruising speed, 11 knots

The same basic hull was modified to build tankers, colliers and other specialized vessels. Some 220 Libertys were fitted out as troop carriers; others were altered for use as hospital ships. The Navy used them variously as repair, picket and training vessels.

A total of 2,710 Libertys were built in 18 different shipyards on the East, West and Gulf coasts. The first one built was named Patrick Henry. She was on the ways for 150 days. Eventually Robert E. Peary took the prize for the fastest construction time: she was launched four days and 15 1/2 hours after her keel was laid, and was ready for sea three days later.

As mass production took hold in the shipbuilding industry, Henry J. Kaiser soon emerged as the leader. Kaiser and his associates, not being traditional shipbuilders, approached the problem simply as a matter of finding a way to mass-produce a product. In their shipyards, bow units, stern units, deckhouses and other major sub-sections were pre-assembled and then welded together to form the ship. This approach resulted in ever-shorter delivery times.

The unprecedented mass production of these ships inevitably produced some problems. Not only was it necessary to construct new yards in which to build these ships, but also vast numbers of workers were needed. Since the U.S. shipbuilding industry had shrunk so drastically, by the 1940s, the supply of experienced shipwrights was equally small.

The lessons of mass production learned in other industries were applied here. Complex jobs were broken down into simple steps that could be accomplished by a worker with very little training, so great numbers of people could be trained quickly.

Of course, as a result of hasty training, there were many defects, but what was really astonishing was that hundreds of ships performed entirely satisfactorily, even though they were built by thousands of men and women who were totally new to shipbuilding.

Welding defects

A series of structural failures occurred with these newly welded ships that became major problems. Some of the failures were the result of defective welds. In other cases, the structural failure was the result of inappropriate uses of welding.

The hulls of several ships split apart in Arctic waters. It was found that the Arctic cold makes ordinary mild steel very brittle. The steel then shatters under strains that would be no problem in more moderate temperatures.

In one instance, a ship split just forward of the deckhouse. The section with the No. 1, 2 and 3 holds sank. The engine room and associated machinery, the deckhouse, living quarters and holds No. 4 and 5 alone remained afloat. The stern half was salvaged and towed into port, where an entire new half was put on.

Life aboard ship

The drama and tragedy of U-boat and air attacks on these ships have been amply described elsewhere. What is seldom mentioned is that unless your ship was badly damaged or sunk, living conditions aboard were pretty good. You got three substantial meals a day and your own bed to sleep in off watch.

The major disadvantage was that if your ship was hit, the odds for its survival were not good. Libertys were built to carry cargo, not to withstand torpedoes, bombs or gunfire.

If your ship sank, your chances of being picked up were poor. If you were seriously wounded or injured, the only person aboard with any medical background had the rating of pharmacist’s mate, with about four months of medical training.

In the merchant fleet during the war, the entire crew was paid off at the end of each trip, and everyone signed off the ship. Each crewmember then had the choice of signing on to the same ship for the next voyage or taking whatever shore leave had accrued.

When a seaman’s leave expired, he could turn down the first two ships he was offered but had to take the third. Merchant seamen thus had an option people in the Navy did not. In the Navy, once assigned to a ship, you stayed until you were ordered elsewhere. Most merchant sailors figured they were better off than in the Army or the Navy. However, statistically this was not so, since the personnel losses in the merchant fleet were higher than the Army, the Navy, the Marine Corps or the Coast Guard, but we didn’t know that until much later.

Libertys were basically carbon copies of each other, so changing ships merely meant a different captain and different crewmembers. Ammo ships and tankers were good ones to stay away from. A mixed cargo of food, machinery, guns, clothing or other not particularly flammable supplies was preferable in case your ship got hit. About 200 Liberty ships were lost to enemy action during World War II.

Libertys in peacetime

By the end of the war, the United States, had a gigantic fleet of new merchant ships, totaling approximately 40 million tons of shipping; three-quarters of them were Libertys. However, the country did not need a large merchant marine, which would actually be a liability, since it would have to be subsidized.

However, the war had clearly demonstrated that a small peacetime merchant fleet was inadequate in the event of a major international crisis.

The Liberty ship had several desirable features for post-war use. It was economical to operate, and it had excellent deck and cargo-handling machinery, as well as substantial cargo capacity for its moderate draft. A Liberty required only removal of the armament and life rafts to make it ready for general service. Britain, Italy, Greece, France, Norway and China, having suffered heavy shipping losses, all wanted and got some. Then a great many others were mothballed and placed in the reserve fleet.

The Korean conflict in 1950 brought all the fast ships — the Victories and C3s — out of retirement, but very few Libertys. Post-war political and military changes meant that ships capable of at least 15 knots were needed.

By the 1960s, both the Libertys in the reserve fleet and those in active service were getting old. By 1967, the reserve fleet was down to about 650 ships, and by 1969, it had dropped to 428.

Today only two of the 2,710 Liberty ships that were built are still afloat: Jeremiah O’Brien in San Francisco and John W. Brown in Baltimore. These are kept in pristine condition by volunteers determined to keep alive the memory of these ships and what they accomplished.

Jeff Markell spent three years aboard Liberty ships during World War II. Serving aboard three different ships, he made multiple crossings of the North Atlantic and came under air attack twice.

By Professional Mariner Staff