 At the time, the number 104 was widely used to designate combat support units in the Maryland National Guard, including the 104th Medical Regiment and the 104th Military Police Battalion.The 104th became the first post-World War I United States National Guard unit to be equipped with its own aircraft, 13 Curtiss JN-4 Jennies, which it flew until 1923.Initially assigned as division aviation for the 29th Infantry Division, the unit operated out of Baltimore's Logan Field.