Yak-1 was the first in A. S. Yakovlev's line of small, nimble fighters. This plane made its combat debut during the defense of Moscow in winter 1941. Series production of Yak-1s started in 1940 in Moscow. Total production was 8712 aircraft. Yak1M version (also called Yak-1b) differs by having a reduced fuselage height behind the cockpit, which gives the pilot a better rear view.