Just arrived from Manila circa 1938.
Starting in San Francisco, the mid-Pacific islands were used as stepping stones for refuelling before reaching Manila. Then a short hop to Macao and Hong Kong. Macao was visited only occasionally after the service became established.
A large American flag emblazoned the fuselage under the pilot's cockpit to warn off any marauding Japanese attackers who were active close by on the coast of China.
Date picture taken
1938