Inverted Jenny

The Curtiss Jenny airplane was first built in 1915 and formed the core of the U.S. Army’s fledgling Air Service in World War I. It was also the favorite airplane of barnstormers and intrepid aviators who could reach speeds of up to 75 mph.

And when the U.S. Post Office initiated the first Air Mail service on May 15, 1918, the mail was flown on a small fleet of Curtiss Jenny airplanes.

The Curtiss Jenny 24¢ stamp was the first-ever Air Mail stamp in U.S. history, and it features a Curtiss Jenny airplane. However, one sheet of 100 stamps was accidentally printed with the airplane upside-down, giving the stamp the famous nickname “Inverted Jenny.” This is one of the rarest and most expensive U.S. stamps, with each example valued at up to $1 million or more.

Stamp Issued:May 13, 1918