formation); re-flagged as Headquarters, Western PVO Front (2nd formation) 2nd formation 24 December 1944 – 9 May 1945 formed from Headquarters, Northern PVO Front Moscow Front PVO 6 April 1942 – 10 July 1943 formed from Headquarters, Moscow PVO Corps Region; re-flagged as Headquarters, Special Moscow PVO Army Southern Front PVO 21 April 1944 – 24 December 1944 formed from Headquarters, Eastern PVO Front; re-flagged as Headquarters, Southwestern PVO Front Southwestern Front PVO 24 December 1944 – 9 May 1945 formed from Headquarters, Southern PVO Front Cold War All the possible air components were divided (as of 1945, before the 1949 reforms of the Soviet Armed Forces) into: Active army (, deystvuyuschaya armiya) – air forces assigned to fighting fronts, known as frontal aviation PVO Territorial Defence Forces (, voiska PVO territorii strany) PVO Territorial Armies (, armiya PVO territorii strany) Reserve forces of the Stavka High Command (, rezerv Stavki VGK) PVO of military districts (, PVO voennyh okrugov) PVO of inactive fronts (, PVO nedeystvuyuschih frontov) The PVO Strany was separated from the other Soviet Armed Forces services in 1949. In June 1949, the 15th Guards Fighter Aviation Division and 180th Guards Fighter Aviation Regiment PVO, among its regiments, were transferred to the PVO Strany, becoming part of the 20th Fighter Air Defence Army at Oryol. There, the regiment became one of the first equipped with the Mikoyan-Gurevich MiG-9, the first of a series of Mikoyan-and-Gurevich Design Bureau jet fighters. In April 1950, the regiment received its first Mikoyan-Gurevich MiG-15s. In May 1954, the PVO Strany was raised to a status equal to the other service branches of the Soviet Armed Forces, receiving its first commander-in-chief: Marshal of the Soviet Union Leonid Govorov. The PVO's principal role was to shoot down United States Strategic Air Command bombers if they penetrated Soviet airspace. Secondary target were U.S. air reconnaissance aircraft. There were a number of such aircraft shot down while operating around the Soviet borders, including MiG-17s downing a US reconnaissance Lockheed C-130 Hercules over Armenia, with 17 casualties in 1958. The PVO gained an important victory on May 1, 1960, when a S-75 Dvina missile downed Gary Powers's U-2, causing the short U-2 crisis of 1960. (See Strategic Air Command#Strategic Reconnaissance) The PVO had its own chain of command, schools, radar and sound director sites. On March 30, 1967, a Directorate of the Chief of Anti-Missile and Anti-Space