1923 8¢ Radiator and Propeller
The first airmail routes between Washington, Philadelphia, and New York were successful. The Post Office Department decided to extend the routes to western cities. Because of accidents and frequent stops, mail traveling by air often took longer to reach its destination than mail sent by train. Many businesses stopped sending their letters by plane in favor of the less expensive and more efficient rail service.
Second Assistant Postmaster General Irving Glover began making plans for the mail to travel by night as well as during daylight hours. The U.S. was divided into three zones and rates would be determined by distance flown. Airmail delivery for a one-ounce letter traveling from one zone to the next was 8¢. New airmail stamps were issued to meet the demand.
The design for #C4 was based on a photograph of the radiator and propeller of a De Haviland plane. The stamp design was approved August 1, 1923. Printing began on the 13th and they were available at the convention two days later.
8¢ Radiator and Propeller, issued to pay the postage on one ounce of airmail for one zone.
Issue Date: August 15, 1923 – At the American Philatelic Society annual convention.
City: Washington, DC, site of the convention
Printed By: Bureau of Engraving and Printing
Printing Method: Flat Plate Printing in sheets of 400, with four panes of 100 per sheet.
Color: Dark Green