Complex sentence: McCook Field was an airfield and aviation experimentation station in Ohio operated by the Aviation Section, U.S. Signal Corps and its successor the United States Army Air Service from 1917 to 1927.
Split into simpler sentences: McCook Field was an airfield and aviation experimentation station in Ohio. It was operated by the Aviation Section, U.S. Signal Corps and its successor the United States Army Air Service from 1917 to 1927.