 Dokashenko was born on 21 November 1921 to a peasant family in Kindrativka village, now Sumy Oblast, Ukraine.In 1939 he completed his ninth grade of school and studied at a local aeroclub.Just a few days before the start of Operation Barbarossa he entered the military, but did not see combat in World War II until June 1944; he graduated from the Chuhuiv Military Aviation School of Pilots in 1943 and was initially assigned to the 22nd Reserve Aviation Regiment.