 On April 30, Lahm reported to New York City along with 1st Lt. Thomas Selfridge and Albert L. Stevens to familiarize 25 members of the 1st Company, Signal Corps, New York National Guard organizing a National Guard balloon unit (the "aeronautical corps") in the use of hydrogen-filled kite balloons.Upon his return from New York, Lahm became head of the Aeronautical Division when Capt.Chandler was transferred to command the Signal Corps Balloon Station at Fort Omaha, Nebraska, on May 13.