The Clerget 9B version 1 is a landmark rotary aircraft engine from the early years of the First World War, representing one of the first truly successful high-power rotary designs. Built by Société Clerget-Blin in France, the 9B laid the foundation for later improvements like the 9Bf and helped establish Clerget as a premier engine manufacturer of the era. This nine-cylinder, air-cooled rotary engine delivered approximately 130 horsepower, offering an excellent balance of power, weight, and reliability for 1916–1917 frontline aircraft. As with all rotary engines, the entire engine rotated with the propeller, providing exceptional cooling and a distinctive gyroscopic effect that strongly influenced aircraft handling. The 9B version 1 featured early carburetion and valve arrangements that, while more demanding to operate than later refinements, were admired for their mechanical simplicity and robust construction. It powered notable aircraft such as early variants of the Sopwith Camel, Sopwith Pup, and several Nieuport fighters, contributing directly to Allied air superiority during the mid-war period.
