In 1937 Pan American ordered only three of these Boeing 307s, at a cost of $315,000 each. They were the first airliners with pressurized cabins. The B307 flew at 220 mph, had a range of 1250 miles. The maiden flight from Miami to Barranquilla, Colombia set a record of six hours and made history as the first inter-continental overwater landplane service. The Boeing 307 had to use the longer runways at Miami Municipal Airport until the runways at 36th Street Airport were lengthened.

Eleanor Roosevelt christened the first B307 with a bottle of water garnered from all the world's Seven Seas. The first Boeing 307 flew December 31, 1938.