The late Bill Larkins photographed this DC-3 at Oakland in the following year, 1940. Here it has not yet received United's 1940 livery with a blue masked cheatline or the name Mainliner San Francisco on the nose. Photo by: Werner Stoy / San Francisco Examiner / UC Berkeley Library

An orderly terminal with gates, built in 1937 at then San Francisco Municipal Airport, or Mills Field. It had two paved runways by 1937. Bottom left is not the fire station - one of the trucks reads US Mail. The parked DC-3 is NC18112. On the left is Lockheed 10 NC14945, which was privately owned. Photo by: Werner Stoy / San Francisco Examiner / UC Berkeley Library

This DC-3 was two years old in September 1939. Later registrations include EC-AXS with Spantax. Apparently survives in South Africa - see Paul Seymour's 2009 photo of this c/n. Photo by: Werner Stoy / San Francisco Examiner / UC Berkeley Library

Gorgeous picture of a 1938 DC-3 at the 1937 terminal at Mills Field, now SFO. In 1939 the airport had 18 scheduled departures on weekdays, 17 United and one TWA. Photo by: Werner Stoy / San Francisco Examiner / UC Berkeley Library