Boeing-built airplane, the B&W, makes its maiden flight from Seattle's Lake Union on June 15, 1916.

On June 15, 1916, William E. Boeing (1881-1956) pilots the B&W Bluebill, the first plane he helped to build, into the air above Lake Union. "B&W" reflected the initials of Boeing and his partner Navy Lt. Conrad Westervelt. Herb Munter (1897-1970) also helped to design and construct the two-seat, single-engine float plane in the Pacific Aero Club's hangar-boathouse at the foot of Roanoke Street in Seattle.

The plane made its second, longer test flight two weeks later. A second B&W, the Mallard was flown in November 1916 from the same location.

Boeing founded the Pacific Aero Club in 1915 and studied flying with Glenn Martin (1886-1955) in Los Angeles. He purchased one of Martin's TA seaplanes and built the Aero Club hangar for it. Anticipating U.S. entry into World War I, Boeing and Navy Lt. Conrad Westervelt hired Herb Munter, one of the first men to build and fly airplanes in Seattle, to assist them in adapting Martin's design to compete for a Naval aircraft contract.

On July 15, 1916, shortly after the B&W's first flight, Boeing incorporated the Pacific Aero-Products Co. Westervelt was assigned to other duties before the B&W flew, and the Navy rejected the B&W design. Following U.S. entry into World War I, Pacific Aero-Products secured a Navy contract for a new float plane, the Model C, and changed its name to the Boeing Airplane Co.

Boeing sold the B&Ws in 1918 to the government of New Zealand, where they were used for training and for that country's first airmail service.

Sources:

Peter M. Bowers, Boeing Aircraft Since 1916 (London: Putnam Aeronautical Books, 1993; N.B. Bowers misnames the first B&W as the Bluebird and cites the plane's second and longer test flight on June 29, 1916.), 33-39; Harold Mansfield, Vision, The Story of Boeing (New York: Popular Press, 1966), 13-16; Robert Serling, Legend & Legacy, The Story of Boeing and Its People (New York: St. Martin's Press, 1992), 2-3; Boeing Historical Archives, Year By Year, 75 Years of Boeing History, 1916-1991 (Seattle: Boeing Co., 1991). 
Note: Munter's claim to have built Seattle's first "native" airplane is doubted by many historians, but he was a pioneer in the local skies. By Walt Crowley, November 23, 1998

Boeing's first plane, a B&W Bluebill, tested in 1916

Courtesy Boeing Archive

Boeing B&W Bluebill, Roanoke Hanger, Lake Union, Seattle, 1916

Courtesy Boeing Archive