The Spruce Goose is probably the most famous, least flied aircraft in the history of flight.
The plane was designed and built by Howard Hughes as a troop transport during World War 2. There was concern we were loosing too many troops as the German UBoats were sinking troop transports on their way from the U.S. to England.
The Spruce Goose was the only one of it’s kind built and was never used to transport troops.
The plane is now the centerpiece of the Evergreen Aviation and Space Musuem in McMinnville, Oregon.