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 and Curtiss.
Curtiss NC-4
This is the Curtiss NC-4 flying boat that completed the first transatlantic crossing on May 8, 1919. The aircraft was designed by Glenn Curtiss and his team, and manufactured by Curtiss Aeroplane and Motor Company. After being disassembled for nearly 40 years, the Smithsonian fully restored the NC-4 and displayed it for a short time on the National Mall for the 50th anniversary celebration on May 8, 1969.
As of 1974, the NC-4 is on loan from the Smithsonian to the National Museum of Naval Aviation in Pensacola, Florida.