With his path across the Atlantic blocked, Juan Trippe surprises even his own staff by turning to the Pacific. Defying the skeptics, Pan Am builds an airway to Asia, allowing its airplanes to hopscotch across the world’s widest ocean by landing at five stepping stone islands: Hawaii, Midway, Wake Island, Guam and the Philippines. Hugo Leuteritz’s radio direction finders point the way, and Igor Sikorsky’s latest flying boat, the S-42, pioneers the route before giving way to the Martin M-130 known as the China Clipper. Within two years, Pan Am is offering regular passenger service to Hong Kong, connecting America and the Asian mainland. Air service from New York to London begins in 1939, completing a chain of airways encircling the globe.

• Stephen Lyons

• Jim Powers