The Fiat CR.42 entered service in 1938 with the Regia Aeronautica and remained active well into WW2. It was used by the air forces of Belgium, Germany, Hungary, and Sweden, and with Italy as their most widely used fighter of WW2.

It was one of the best biplanes fighters around, but quickly became overshadowed by the new monoplane designs at the beginning of the war. Various versions were made, including a ground-attack, night-fighter, and trainer.

The CR.42 was armed with 2 x 7.7mm or 2 x 12.7mm machine guns, with some versions having extra guns or bomb racks.