The South African
Military History Society

Die Suid-Afrikaanse Krygshistoriese Vereniging



Military History Journal
Vol 12 No 5 - June 2003

LIBERTY SHIPS

by A V Weinerlein

Prior to the Second World War, estimates showed that some 2 000 British merchant ships were plying the oceans of the world, participating in their commercial ventures. Britain was dependent on its merchant navy for the majority of its vessels. At the outbreak of war, German surface raiders like the Graf Spee and U-boats were already in position in the Atlantic and the Indian oceans, prepared to attack any British and Allied ships that crossed their path. Sea mines were laid in the shipping lanes of the English Channel and the European coasts, and even in the waters around Cape Town, South Africa. Long range German Kondor aircraft began to menace shipping in the North Atlantic.

The Allied navies were hard-pressed to scour the oceans in pursuit of the prowling enemy vessels. The destruction of the Graf Spee at the River Plate was small relief. The early success of the ruthless German Navy inflicted crippling shipping losses on the Allies. With the capitulation of France, the enemy gained many advantageous bases from which to operate their naval vessels. By the end of 1940, over three hundred British ships had been sunk and Britain's accelerated merchant ship building programme had no hope of replenishing the increasing losses due to enemy action.

In the latter part of 1940, Britain placed orders with America to build ships for her merchant navy. At this time, America, perturbed by the adverse shipping losses which Britain was facing, embarked on an emergency replacement ship building programme in order to cover possible losses should they themselves become embroiled in the war.


Keeping up production, workmen lay the keel of another Liberty ship. (Photo: Libertas, January 1943, p 52).

The complete prefabricated transverse bulkhead is lowered into position in the hull of the new ship. (Photo: Libertas, January 1943, p 52).

The massive poop deck is manouevred into position. (Photo: Libertas,January 1943, p 53).

Following discussions between Britain and America on their shipping needs, a standard type of merchant ship which lent itself to mass production was selected. This ship was later to be known as the 'Liberty Ship'. The important features of the new type of ship was that it would be built of steel and welded, having a slightly blunted raked bow with a cruiser stern and a flush deck. The midship decks would accommodate both officers and crew, doing away with the old uncomfortable crew quarters in the fo'c's'le. The engine was to be 2 500 horse power driving a single propeller with a speed of ten knots, carrying a cargo load of 10 000 tons in five cargo holds. The covers of these holds were to be made of steel and wood to be used as rafts in the event that the ship was sunk. The ship would be fitted with suitable armament for defence against both enemy vessels and aircraft.

During 1941, Henry J Kaiser, who had never been associated with ship building, was entrusted with managing the Emergency Ship Building Programme. He was to revolutionise the concept of shipbuilding. It was said that he was 'producing' ships rather than 'building' them.

Huge tracts of coastal and swamp areas were cleared along the Atlantic, Pacific and Gulf coastal areas. The use of swamp areas allowed slipways to be positioned below sea level to aid launching of the ships. For example, the Atlantic area consisted of eight shipyards with 62 slipways.

Some 600 000 men and women from all walks of life were recruited and trained in skills required for mass production of the ships. Towards the end of 1941, the production of Liberty ships got under way and increased at a good rate due to the assembly line method. The keel of the ship would be placed in the slipway, the hull section attached to the keel, and other components such as the engine, the bow, the stern, the boat deck, the engine room and bulkheads, which were fabricated in assembly areas near to the slipway, would be transported to the awaiting hull and manouevred by huge cranes to their allotted positions in the ship. The whole structure would then be welded together. All the deck appurtances were then fitted to the deck, the protective armaments secured at the vulnerable points. The ship, completed, was then launched.

The time spent on assembling a Liberty ship was steadily reduced from thirty-nine days to an average of fifteen days. In one instance, a Liberty ship was assembled in four days, fifteen and a half hours, a once-off effort never to be repeated.


During 1942, with America entering the war, there was a large increase in shipping losses, reaching critical levels when some 1 664 ships were lost. As the Liberty ships were being launched, they were pressed into service at the end of 1943. With the increase in naval escort ships and the replacement of merchant shipping losses by Liberty ships, the battle against the U-boats was gradually being won.

The Liberty ships were prone to certain types of damage owing to the methods used in their production. In particular, the ships had a weakness amidships, where the welded joints did not have sufficient flexibility, and this resulted in cracks across the deck and, in some cases, the ships broke apart. This problem was overcome by placing rivetted plates over the cracks which provided the required flexibility for the movement of the welded hull.

The frugal Liberty ship stood up to intense bombing and U-boat action, adverse weather conditions and heavy seas, acquitting itself well and beyond expectations. The relentless land and sea offensives around the world helped in defeating the enemy on all fronts. The mainspring of victory was the overwhelming sea power of the Allies and the abundance of Liberty ships was a big contribution to this. By the end of the war, 2 710 Liberty ships had been built, of which 200 were sunk by enemy action. Six Liberty ships were sunk off the South African coast by U-boat attacks.

At the end of the war there was a huge surplus of Liberty ships. In the post-war era, they enabled shipping companies around the world to re-establish regular sailings across the oceans.

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