The flying boat NC-4 was the first airplane to fly across the Atlantic Ocean in 1919. In the 1920s and 1930s, flying boats made it possible to have regular air transport between the US and Europe, opened up new air travel routes to South America, Africa, and Asia. Where land-based aircraft lacked the range to travel great distances and required airfields to land, flying boats could stop at small island or coastal stations to refuel and resupply. The PanAm Clipper planes brought exotic destinations like the Far East in reach of air travelers and came to represent the romance of flight.
The military value of flying boats was quickly recognized, and they were utilized by various nations in tasks from anti-submarine patrol to maritime search and rescue. Aircraft such as the PBY Catalina recovered downed airmen and operated as scout aircraft over the vast distances of the Pacific Theater during World War II.
Several factors contributed to the decline of flying boats. As the speed and range of land-based aircraft increased, the need for flying boats diminished. Their design compromised aerodynamic efficiency and speed to accomplish the feat of waterborne takeoff and landing. Competing with new civilian jet aircraft like the Boeing 707 was impossible. Helicopters overtook the flying boats in their air rescue roll. The land-based P-3 Orion and carrier-based S-3 Viking became the US Navy's fixed-wing anti-submarine patrol aircraft.
The pinnacle of flying boat design was surely the Hughes H-4 Hercules, known as the "Spruce Goose." The largest plane ever to fly, the Spruce Goose flew only once. The age of the flying boats was largely at an end, and the massive plane was seen as a dinosaur from a bygone era.
True flying boats have largely been replaced by seaplanes and amphibian aircraft.
