24c "Inverted Jenny" block of four stamps

One of the most iconic and recognizable stamp errors ever discovered is the 1918 24c "Inverted Jenny" air post stamp. In 1918 the Post Office issued its first air mail postage stamp, to promote the newly established air mail service. A special 24c stamp was prepared, depicting the "Curtiss Jenny" biplane in the center in blue, surrounded by a red frame. One sheet of 100 stamps was discovered with all of the stamps within the sheet having had the blue biplane in the center printed upside down.

From the original sheet of 100, only six blocks of four still exist - four of which are contained within the William Gross collection. He has loaned one of these spectacular blocks of four, the unique left sheet margin block of four (positions 41-42/51-52) to the Smithsonian National Postal Museum.

Scott Catalogue USA: C3a

Loan from William H. Gross.

Museum ID: 2013.6617.1.1-4