Russian Decapod Steam locomotive (class Ye). The Russian locomotive class Ye, and subclasses Yea, Yek, Yel, Yef, Yem, Yemv and Yes (Russian: Паровоз Е; Еа, Ек, Ел, Еф, Ем, Емв and Ес) were a series of 2-10-0 locomotives built by American builders for the Russian railways in World War I and again in World War II. They were lightweight engines with relatively low axle loadings.