Boeing 707 version was numbered 707-320. Pan Am was the first airline to operate the 707; the carrier inaugurated 707 service with a christening at National Airport on October 17, 1958, attended by President Eisenhower, followed by a transatlantic flight for VIPs (personal guests of founder Juan Trippe) from Baltimore's Friendship International Airport to Paris. The aircraft's first commercial flight was from Idlewild Airport, New York, to Le Bourget, Paris, on October 26, 1958, with a fuel stop in Gander, Newfoundland. In December, National Airlines operated the first U.S. domestic jet airline flights between New York/Idlewild and Miami, using 707s leased from
Boeing but the design experience was used in the development of the Model 314 that followed a year later. Overlapping with the period of the YB-15 development, an agreement with Pan American World Airways (Pan Am) was reached, to develop and build a commercial flying boat able to carry passengers on transoceanic routes. The first flight of the Boeing 314 Clipper was in June 1938. It was the largest civil aircraft of its time, with a capacity of 90 passengers on day flights, and of 40 passengers on night flights. One year later, the first regular passenger service from the U.S.