This was not an easy one to research today–not all sites appear to agree or give the same information. However, it appears to be true that on this date in 1919, Glenn Curtiss flew the Curtiss NC-4 landed in Lisbon, Portugal, thus completing the first successful trans-Atlantic flight. He had begun nineteen days before at New York, and this was the end of his journey. It was one of three planes that made the flight (NC-2 was dismantled so parts from it could be used for the other three planes). In spite of very thick fog, this plane was able to land safely through radio transmission.
Interestingly enough, he began as a motorcycle manufacturer, and after seventeen years in the airplane business, he retired as a multi-millionaire. He was a pretty successful guy–kind of the epitome of the American Dream in so many ways.
For more info:
http://en.wikipedia.org/wiki/Glenn_Curtiss
http://famousdaily.com/history/first-transatlantic-flight.html
http://www.glennhcurtissmuseum.org/educational/glenn_curtiss.html
http://www.factbites.com/topics/Glenn-Curtiss
http://en.wikipedia.org/wiki/Curtiss_NC-4
http://www.456fis.org/CURTISS_%20AIRCRAFT_COMPANY.htm