From Old Fort Brown Cavalry Drill Field near this spot came the first flight of a U.S. Army plane to be fired upon in armed hostilities on April 20, 1915. Two Signal Corps officers, Lts. Byron Q. Jones and Thos. Milling, flew a Martin T.O. Curtiss 75 on the border to observe the movements of Mexican revolutionist Pancho Villa. They reached 2,600 feet and remained aloft for 20 minutes. Although they did not cross the Rio Grande, the plane was hit by machine-gun and small-arms fire. Their patrols continued for 6 weeks, and planes were used more effectively in fighting against Villa in 1916.