Upon the start of the war the flotilla was reinforced by an additional another one shore battery (122mm A-19), in exchange for the transfer of the four launches to the Black Sea Fleet.
[1] At the beginning of the Romanian–German invasion of the Soviet Union on June 22, 1941, the Flotilla cooperated with Red Army troops in the defense of the southern front.
[4] Flotilla operations included assisting in landings at Raduevats and Prahovo on September 29–30, 1944 (even well into the 21st century, the wrecks of about 200 vessels sunk by the Germans to block the landings remain in the Danube at Prahovo),[5] at Smederevo on October 16, at Vukovar on December 8–10, at Gerjen on November 30–December 1, at Esztergom on March 19–23, 1945, and at Radwanska on March 28–30.
[6] For its combat exploits, the 1st Guards Armored Boat Detachment (an element of the Danube Flotilla) was awarded the Order of Kutuzov 2nd Class.
[citation needed] At this time, the standard armored boat in production, and forming part of the strength of the Danube Flotilla,[7][failed verification][self-published source?]