The Junkers CL.I was a ground-attack aircraft developed in Germany during World War I. Its construction was undertaken by Junkers under the designation J 8 as proof of Hugo Junkers' belief in the monoplane, after his firm had been required by the Idflieg to submit a biplane (the J 4) as its entry in a competition to select a ground-attack aircraft. The J 8 design took the J 7 fighter as its starting point, but had a longer fuselage to accommodate a tail gunner, and larger wings.