Initially, concerns for secrecy kept the military designation of the Katyushas from being known by the soldiers who operated them.
Because they were marked with the letter K (for Voronezh Komintern Factory),[REF] Red Army troops adopted a nickname from Mikhail Isakovsky's popular wartime song, "Katyusha", about a girl longing for her absent beloved, who has gone away on military service [REF].