First flight air mail cover addressed to William E. Boeing, Chicago, Illinois, July 1, 1927.Stamped: "First Flight Under Contract - Chicago to San Francisco - Transcontinental Air Mail Route, Omaha, Nebraska."
First flight air mail cover addressed to Master Bebo Boeing, Seattle, Washington, July 1, 1927. Stamped: "First Flight Under Contract - Chicago to San Francisco - Transcontinental Air Mail Route, Omaha, Nebraska."