The NC-4 was a Curtiss NC flying boat that was the first aircraft to fly across the Atlantic Ocean, albeit not non-stop. The NC designation was derived from the collaborative efforts of the Navy (N) and Curtiss (C). The NC series flying boats were designed to meet wartime needs, and after the end of World War I they were sent overseas to validate the design concept.
The aircraft was designed by Glenn Curtiss and his team, and manufactured by Curtiss Aeroplane and Motor Company, with the hull built by the Herreshoff Manufacturing Corporation in Bristol, Rhode Island.
In May 1919, a crew of United States Navy and US Coast Guard aviators (https://cgaviationhistory.org/1919-nc-4-transatlantic-flight/) flew the NC-4 from New York State to Lisbon, Portugal, over the course of 19 days.
The transatlantic capability of the NC-4 was the result of developments in aviation that began before World War I. In 1908, Glenn Curtiss had experimented unsuccessfully with floats on the airframe of an early June Bug craft, but his first successful takeoff from water was not carried out until 1911, with an A-1 airplane fitted with a central pontoon. In January 1912, he first flew his first hulled “hydro-aeroplane”, which led to an introduction with the retired English naval officer John Cyril Porte who was looking for a partner to produce an aircraft with him to attempt win the prize of the newspaper the Daily Mail for the first transatlantic flight between the British Isles and North America – not necessarily nonstop, but using just one airplane. (e.g. changing airplanes in Iceland or the Azores was not allowed.)
Emmitt Clayton Bedell, a chief designer for Curtiss, improved the hull by incorporating the Bedell Step, the innovative hydroplane “step” in the hull allowed for breaking clear of the water at takeoff. Porte and Curtiss were joined by Lt. John H. Towers of the U.S. Navy as a test pilot.
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The NC-4 is property of the Smithsonian Institution, since it was given to that institution by the Navy after its return home. However, this aircraft was too large to be housed in either the older Smithsonian Arts & Industries Building in Washington, D.C., or in its successor, the 1976-completed National Air and Space Museum main building, also in Washington. A smaller model of the NC-4 is kept in the Milestones of Flight Gallery in the National Air and Space Museum, a place of honor, along with the original Wright Flyer of 1903;
The NC-4 was a Curtiss NC flying boat that was the first aircraft to fly across the Atlantic Ocean, albeit not non-stop.