HNMLS Jacob van Heemskerck was a Dutch light cruiser, keel laid in October 1938, launched in September 1939, and entry into service in 1940. The vessel was about 132 meters long with a width of about 12.4 meters. The standard displacement did not exceed 4,200 tons, and the maximum speed was up to 33 knots. The ship's armament consisted of: 10 102 mm guns, 8 40 mm AA guns and 8 20 mm AA guns. The unit could also put mines. HNMLS Jacob van Heemskerck was the second and last Tromp class vessel. Originally, vessels of this type were built to protect Dutch possessions in what is roughly what is now Indonesia, and their main potential enemy was seen in the light naval forces of the Empire of Japan - especially its destroyers. While the first unit of this type (HNMLS Tromp) was completed as originally planned, HNMLS Jacob van Heemskerck, not yet fully completed, was evacuated to Great Britain at the time of the German invasion of Western Europe in May 1940. There it was rebuilt into an anti-aircraft cruiser (eng. air defense cruiser) and served in this role during World War II. Its reconstruction was completed in 1941 and initially served as a cover for Atlantic convoys, but in January 1942 it was sent to the Dutch East Indies. However, during the voyage to this area, it turned out that the forces he was to join had already been defeated by the Japanese, and therefore he was directed to Ceylon. In September 1942, he supported landing operations in Madagascar, and later covered convoys in the Indian Ocean. From December 1943 to June 1944, he served in the Mediterranean, and from June 1944 until the end of the war, he remained in a repair shipyard in the British Isles. From September 1945 to July 1946, it operated in the area of today's Indonesia, and in 1947 it was reclassified into a school unit. In 1969, the unit was removed from the fleet list, and in 1970 it was sold for scrap.