*Revolution and disorder in Mexico and trouble along the U.S.-Mexican border in March 1913 brought on the hurried organization of the 1st Aero Squadron, the U.S. Army’s first tactical unit equipped with airplanes. In 1916, the squadron took part in General Pershing’s punitive expedition into Mexico in pursuit of Mexican revolutionist Pancho Villa. Difficulties along the border continued while the United States was at war in Europe. Mexican bandits often raided American ranches to secure supplies, cattle, and horses, and in doing so sometimes killed the ranchers. U.S. troops stationed along the border shot raiders as they pursued them into Mexico. The biggest clash came in August 1918, when more than 800 American troops fought some 600 Mexicans near Nogales, Arizona.

   Border patrol was one of the many activities being considered for the postwar Air Service. However, no aviation units had been assigned to duty on the Mexican border, when a large force of Villistas moved northward in June 1919 toward Ciudad Juarez, Chihuahua, Mexico (opposite El Paso, Texas), garrisoned by Mexican government forces. Maj. Gen. DeRosey C. Cabell, Commanding General of the Southern Department, received orders to seal off the border if Villa took Juarez. If the Villistas tired across the border, Cabell was to cross into Mexico, disperse Villa’s troops, and withdraw as soon as the safety of El Paso was assured. The General ordered Air Service men and planes from Kelly and Ellington Fields, Texas, to Fort Bliss, near El Paso, for border patrol American troops under Brig. Gen. James B. Erwin, Commander of the El Paso District of the Southern Department, were on alert when about 1,600 of Villa’s men attacked Juarez during the night of June 14/15, 1919. Stray fire from across the river killed an American soldier and a civilian, and wounded two other soldiers and four civilians. Around 3,600 U.S. troops crossed into Mexico, quickly dispersed the Villistas, and returned to the American side. Air Service personnel with DH-4 aircraft began arriving at Fort Bliss on June 15.

   Maj. Edgar G. Tobin, an ace who had flown with the 103d Aero Squadron in France, inaugurated an aerial patrol on the border on the 19th. By mid-September the force grew to 104 officers, 491 enlisted men, and 67 planes from the 8th, 9th, 11th, 90th, and 96th squadrons. In the summer of 1919, the Army planned to build at least nine aero squadrons and one airship company for surveillance of the entire border from the Gulf of Mexico to the Pacific Ocean. The plan called for two observation squadrons (the 9th and 91st) of the Western Department to patrol eastward from Rockwell Field, California, to the California-Arizona line. Three surveillance squadrons (the 8th, 90th, and 104th) and four bombardment squadrons (the 11th, 20th, 96th, and 166th) of the Southern Department were to be distributed along the border from Arizona to the Gulf of Mexico. On July 1, 1919, the three surveillance squadrons organized into the Army Surveillance Group headquartered at Kelly Field. (This group became the 1st Surveillance Group in August 1919.) In September the four bombardment squadrons formed the 1st Day Bombardment Group, also with headquarters at Kelly. In addition the 1st Pursuit Group and its squadrons (27th, 94th, 95th, and 147th) moved from Selfridge Field, Michigan, to Kelly at the end of August to be available if needed. The three groups (surveillance, day bombardment, and pursuit) comprised the 1st Wing at Kelly. Commanded by Lt. Col. Henry B. Clagett, the wing became responsible for aerial patrol of the border in the Southern Department. Also in August, work started on a large steel hangar for an airship station at Camp Owen Bierne, Fort Bliss.

   The Army soon scaled down the plan for border patrol. Although minor incidents continued to occur, Pancho Villa never succeeded in rebuilding his force. The major threat had been dispelled by the time aerial patrol began.

   From January 1920 on, the patrol in the Southern Department was handled by the 1st Surveillance Group which had moved its headquarters to Fort Bliss and gained an extra squadron, the 12th. The group’s squadrons operated in two flights, each patrolling a sector on either side of its operating base. From the Gulf of Mexico westward, the deployment was as follows:

8th Squadron  McAllen and Laredo, Texas,  90th Squadron  Eagle Pass and Sanderson, Texas,  104th Squadron  Marfa and El Paso, Texas,  12th Squadron  Douglas and Nogales, Arizona .

*Aviation in the US. Army,1919-1939
 Maurer Maurer
 United States Air Force Historical Research Center