To the Navy and other branches of the service afloat, and to those engaged in amphibious operations, life preservers and invasion jackets are of vital importance. They not only enable personnel forced into the sea to remain afloat but they also perform the important corollary function of providing a measure of protection against flying fragments during combat operations. Some of the background and problems encountered in maintaining a continuous flow of buoyant raw material for lifesaving equipment in World War II combine to provide a story both interesting and dramatic.
Cork was formerly used in Navy life jackets but was replaced by kapok some twenty years ago. Kapok had been found to be lighter in weight for a given buoyancy and was much more comfortable and pliable to wear. Moreover, under conditions existing in this war, personnel forced to jump into the water from ships while wearing slab cork life preservers would have been easy victims of such injuries as broken necks, arms, and collar bones. Through the end of World War II, the United States Navy used two general types of life preserver—one filled with kapok and the other inflated with carbon dioxide and especially designed for use by troops on troop-carrying transports.
In view of the fact that the United States was almost entirely dependent upon the Netherlands East Indies for its pre-war supply of high quality kapok and because of the loss of that source early in the Pacific War, we suddenly became almost entirely dependent upon an accumulated stockpile of Java kapok and were faced with the problem of developing other sources of supply and of experimenting with myriad substitute materials to replace kapok when the stockpile became exhausted. The following paragraphs contain a review of action taken before the war in anticipation of this eventuality, the controls that were undertaken by the War Production Board and the Navy to conserve stocks of buoyant kapok for use in lifesaving equipment, and the constant search for substitute materials that ultimately has resulted in the adoption by the Navy of fibrous glass to replace kapok in lifesaving equipment.
True Java kapok is the flossy, silky fiber obtained from the ripened pods of the Ceiba Pentandra tree of the family known as Bombacaceae, a large family of trees comprising some 20 genera and 120 species. Kapok trees flourish best in porous, sandy clay soil of volcanic origin and in tropical regions having distinct dry and rainy seasons. The dry season should come in just as the kapok flowers appear and should last until after the pods are harvested. Kapok trees start bearing pods when they are about four years old, but they do not come into full bearing until several years later. An average tree seven years old will produce 350 to 400 pods or 3½ to 4 pounds of floss. True kapok trees grow in Java, India, Ceylon, Tanganyika, Kenya, Zanzibar, French West Africa, Indo-China, Burma, the Philippines, and in Ecuador, Paraguay, and throughout the West Indies in the Western Hemisphere. In 1893 the Netherlands Government exhibited kapok floss at the World’s Columbian Exposition in Chicago, and that year marks the emergence of kapok as an important commodity in world trade. While hailed initially as a new textile fiber, its use in this direction has not materialized because the fiber is too smooth, straight, and short to permit satisfactory spinning.
On the other hand, its thin-walled, air- filled cells, covered with a waxy substance on the outside, provide its accepted qualities of high buoyancy, resiliency and light weight; in addition, its nonconductivity has resulted in widespread use in thermal and acoustical insulating applications. Major civilian uses before the war were in mattresses, pillows, upholstery, sleeping bags, toys, sports equipment, and in sound and heat insulation. Military uses that still prevailed early in World War II included life preservers, sleeping bags, marine mattresses, pontoon bridges, and sound-deadening linings in tanks and airplanes.
Military needs for kapok resulted in this material being classified as “strategic and critical” early in World War II. Realizing that the heavy Navy shipbuilding program would inevitably result in commensurate increases in life-preserver requirements, the Bureau of Supplies and Accounts on July 3, 1940, suggested that the Army and Navy Munitions Board procure from funds appropriated under Public Act No. 117 a minimum quantity of kapok to satisfy estimated Navy needs for approximately two years. Meanwhile, the Office of the Chief of Naval Operations worked in close cooperation with the Army and Navy Munitions Board towards the goal of prior provision by accumulating both a government stockpile of kapok under Public Act No. 117 and a Navy-owned reserve supply.
The original public purchase recommendation covering Java kapok was authorized during June of 1941 and was for a total of 2,000 long tons; this was augmented by an authorization dated January 30, 1942, for 5,000 long tons or a total stockpile objective of 15,680,000 pounds. Subsequent authorizations on Java kapok were approved to purchase 700,000 pounds held by domestic users and 600,000 pounds for transfer from Australia’s stockpile. And so, against total authorizations for 16,980,000 pounds of Java kapok, the government purchased and received delivery of 13,378,000 pounds. To supplement this supply, the Navy Department as of October 1, 1942, had been able to purchase and obtain delivery of 1,752,189 pounds of Java kapok as a special reserve to be used in its own manufacturing facilities at Philadelphia and Mare Island Navy Yards.
In addition, stocks of Java kapok imported and held by industry were frozen early in the war and were directed into wartime permitted end uses under General Conservation Order M-85 issued by the War Production Board. Other important additions to the supply of buoyant material were derived from production in Ecuador, another transfer from the Australian stockpile in 1945, and from collections of milkweed floss in the United States during 1943 and 1944.
The War Production Board issued Order M-85 on February 4, 1942, in order to conserve the supply, direct the distribution, and allocate the supply of Java kapok. Subsequent amendments extended these controls to kapok obtained from other sources. As the order was originally issued, kapok could be used in applications then considered to be the most essential and included life buoys and preservers, sleeping bags, mattresses, pillows, blankets, pontoon bridges, aircraft insulation, stuffing for air tanks of boats, rafts and lifesaving appliances, provided all of the foregoing were for the Army, Navy, and other “military claimants”; in addition, kapok was then permitted as insulation for food-carrying freight cars and trucks and for industrial refrigeration of food. As the war developed, it became obvious that the use of kapok in aircraft insulation was expanding so rapidly that this requirement would soon consume all available supplies, so steps were begun in 1942 to limit this insulation to a 45 per cent kapok content and, on January 28, 1944, the War Production Board restricted the use of Java grades of kapok to the manufacture of life vests, jackets, and collars. This action conserved an estimated 3,500,000 pounds of kapok required in aircraft insulation alone and resulted in the development and substitution of fibrous glass for this end use. And Order M-85 still continued to confine the use of Java and other buoyant grades of kapok to the manufacture of life preservers during the remainder of World War II.
During the period from 1929 through 1938, exports by all principal producing countries of kapok averaged approximately 54,000,000 pounds, of which total the United States imported annually an average of just over 22,000,000 pounds for the same period. The Netherlands East Indies were by far the most important factor in this raw material, exporting three-fourths of the total of all exporting countries and providing nearly 95 per cent of the kapok imported into the United States. As recently as 1939, the Navy required only about 75,000 pounds of kapok for its production of life preservers, but by 1943 this figure had risen to nearly 4,000,000 pounds and, in 1945, the Navy required nearly 7,000,000 pounds of buoyant kapok and milkweed floss for use in life preservers and invasion jackets!
Back in 1940 the possibility of war in the Pacific and of losing the Netherlands East Indies as a source of supply for kapok was given due consideration by the Navy and investigations were begun on a variety of alternate materials that might prove suitable for use in life preservers. This comprehensive research program involved careful investigation and tests on nearly forty different natural and synthetic materials, of which fibrous glass, milkweed floss, wax treated cotton, and cattail floss showed the most promise.
In July of 1943, a program was set in motion by the War Production Board to have milkweed pods collected and their floss extracted or cleaned at a plant in Michigan. Tests already conducted on this material indicated that it would be an adequate substitute and it was expected that 1,000,000 pounds of milkweed floss could be collected and processed in 1943, 3,000,000 pounds in 1944, and 5,000,000 pounds in 1945. Actually, however, only 88,000 pounds were realized in 1943 and, when the program was completed in August of 1945, only about 1,600,000 pounds cumulative total resulted from collections and processing since 1943. Furthermore, the milkweed pods of necessity were collected from wild plants in various localities throughout the country, the floss showed variable quality, and this material did not provide the buoyancy indicated by earlier tests. Nevertheless, it has adequate buoyancy for invasion jackets and was incorporated into this one-use jacket.
By authority of a directive from the Joint Chiefs of Staff, the Navy Coordinator of Research and Development on December 16, 1943, assembled representatives of all cognizant agencies for the purpose of organizing a joint committee on emergency rescue equipment. As a result of analysis conducted by this group’s subcommittee on materials, the Navy was invited to send a mission to Ecuador in the summer of 1944 to ascertain the volume of buoyant kapok that could be produced there; and, as the result of improving their cleaning methods and urging them to increase their output, over 500,000 pounds of acceptable quality kapok were received from Ecuador in 1944. A similar mission of Navy personnel was sent to Ecuador in 1945 at the request of the Foreign Economic Administration and arrangements were made to procure and grade their entire 1945 crop, which was counted upon to provide a minimum of 750,000 pounds of kapok to meet Navy’s minimum standard for buoyancy.
The other important action resulting from the work of this subcommittee on materials was assigning a project in June of 1944 to the National Research Council for the specific purpose of developing a synthetic material suitable as a substitute for kapok in life preservers, the resultant approved material to be available for delivery to the armed services by June of 1945. This project was placed under the leadership of a representative from the Mellon Institute of Industrial Research. The efforts of this research culminated in designation and acceptance by the Bureau of Ships of fibrous glass type “A” fiber as the synthetic material with the most advantageous characteristics as a substitute for kapok in Navy life preservers.
In spite of the most stringent conservation measures and the careful husbanding of all available supplies of usable new and reclaimed kapok, and in view of constantly increasing requirements for life preservers and invasion jackets, it became apparent that our stocks of kapok would be completely exhausted by the end of 1945. Having decided upon fibrous glass as the most desirable material to replace kapok, it was necessary to make provision months in advance of the end of 1945 for the needed volume of production of this new material. As a matter of coincidence, it so happened that the Navy approached the War Production Board on V-E Day to formulate a procedure for providing the necessary facilities. Working as a team on this urgent program, the Navy, War Production Board, Reconstruction Finance Corporation, and the sole commercial producer of the adopted substitute overcame many production problems, notably locating two available plants with suitable physical specifications, necessarily located where critically short man power could be provided and in an area which could furnish an adequate supply of gas for the projected production. Through close co-operation on the part of the Army Air Forces, their North American Modification Center in Kansas City, Kansas, was made available and the surplus plant of the Aluminum Corporation of America in Kansas City, Missouri, was acquired; the Navy entered into a supply contract with the Owens-Coming Fiberglas Corporation to produce the fibrous glass, the War Production Board placed the project right up near the top of its special military programs, machinery and equipment orders were placed and expedited, and the program was under way to produce a supply of buoyant material in sufficient volume to satisfy all Navy requirements for use in life preservers commencing in January of 1946. No chances could be taken on provision of a continuous supply of lifesaving equipment for prosecution of the war in the Pacific.
When the war with Japan came to a successful conclusion in August, the Navy and the Reconstruction Finance Corporation moved immediately to cancel out this program, but with the understanding that the contractor would arrange to produce “A” type fibrous glass commercially for the Navy without government facilities or financing. This new material had already demonstrated its superiority over kapok because it was fire and mildew proof, had superior buoyancy qualities, could withstand repeated wetting and drying with little loss in efficiency, and could be produced domestically in uniform quality without dependence of any nature upon far removed and uncertain sources of supply.
Thus by making prior provision for this emergency by accumulating a stockpile before the war, by careful planning and conservation, our kapok stocks served the Navy and other military claimants throughout World War II while other available materials were being investigated and tested until, born out of necessity, a new synthetic material was developed which proved so superior to the traditional kapok that it has now been adopted by the Navy as the standard of quality for buoyant material to be used in life preservers.