The T9 "Locust" light tank was designed during World War II to support airborne operations. The Locust was primarily used for training instead of combat. This was because it was too heavy to be transported by anything but the largest aircraft, and too lightly armored to survive on the battlefield. The Locust displayed at Memorial Field had its 37MM gun removed. In 1946, Rock Island Arsenal sold 100 T9 tanks as farm tractors for $100 each.From the Battlefield to the CornfieldThe T9E1 was an experimental modification of the M22 light airborne tank that was developed by the United States during World War II. Production began in 1942 but, due to changes in design, mass production did not begin until 1943. While over 2,000 tanks were ordered by the United States and Britain, only 830 were produced and delivered.The Locust was burdened with design flaws. The tank was supposed to be air-deployable and lightweight; however only the Douglas C-54 Skymaster was capable of carrying it. The British Hamilcar Mark I was the only British aircraft capable of airlifting and dropping the tank as well. As a result, the tank was not suitable to fulfill its designated mission.The Locust tank weighed in at almost seven and a half tons, with poor armor design leading it to be little more than a battlefield steel coffin. Few saw any action during World War II, and all were retired by 1948 after the Arab-Israeli War.At the end of World War II, the federal government opted to liquidate its inventory of the tanks by selling them to private owners. Rock Island Arsenal obtained 100 of these tanks for sale to local farmers. At least two other tanks remained at Rock Island Arsenal and were used to plow snow through the 1950s. Post-war M22 tanks were stripped of their 37MM gun and their M1919A4 Browning machine guns.