William Boeing, Jr. net worth: William Boeing, Jr. was a real estate developer and businessman who had a net worth of $200 million. William Boeing, Jr. was born in November 1922 and passed away in January 2015. William was the son of Boeing Company founder and aviator pioneer William Edward Boeing. William Jr. also served as a member of the Seattle Museum of Flight board of trustees. He was honored with a certificate of achievement for having a commitment to education and for his efforts at preservation of air and space history by the American Institute of Aeronautics and Astronautics. Boeing, Jr. was instrumental in making sure that the birthplace of the Boeing Company called the Red Barn, which is the oldest airplane manufacturing facility in the United States, was preserved and became integrated into the Seattle Museum of Flight. William was married to his wife June and his first wife Marcella Cech passed away in 1990. His son William Boeing III passed away in 2013. William Boeing, Jr. passed away on January 8, 2015 at the age of 92.