Famous racing pilot 'Colonel' Roscoe Turner leased the first Boeing 247D from United Airlines for his partiicipation in the MacRobertson Air Race. It is seen here over the USA already wearing its race number 5. The number 57, referring to Heinz's 57 ketchup varieties, and the name Warner Bros. Comet were added to please Turner's sponsors. Photo from: San Diego Air & Space Museum
This photo was added on 17 May 2019, and has since been viewed 38 times.