Photograph of JR-1B mail airplane designed by the Standard Aircraft Corporation
In 1918 the Standard Aircraft Corporation of Plainfield, New Jersey, redesigned six of their 1918 E-4 airplanes for airmail service, fitting them with 150-horsepower Hispano-Suiza engines and longer top wings. The redesigned aircraft were purchased by the Post Office Department. Airmail pilot Max Miller painted a U.S. mailbag on the side of this airplane, numbered 1.
National Postal Museum, Benjamin Lipsner Collection