had once crossed into Murmansk airspace, and had to make an emergency landing when a Soviet Air Force Su-15 fired on it. Soviet government officials finally admitted their mistake much to the anger of the South Korean and the United States governments. It even resulted in the forced and sudden resignation of the then Armed Forces Chief of the General Staff, Marshal Nikolai Ogarkov, in the following year by the Chairman of the Presidium of the Supreme Soviet of the Soviet Union (leader of the Soviet Union) Konstantin Chernenko. Mathias Rust's flight to Moscow in May 1987 caused a massive shakeup within the PVO. It seems that after the KAL 007 shootdown of 1983, no one was willing to give an order to bring Rust's tiny Cessna 172 down, and modernization programmes within the PVO had led to the installation of radar and communications systems at the state border that could not effectively pass tracking data to systems closer to Moscow. PVO Commander-in-Chief Marshal A. I. Koldunov was only among the first to be removed from his position. Over 150 officers, mostly from the PVO, were tried in court and removed from their posts. A large-scale changeover of senior officers of the force more generally followed as well. Under the Russian flag When the Soviet Union dissolved, the air fleet of the PVO included roughly 2,200 fighters and interceptors. The personnel and equipment of many units were left in newly independent republics, although the impact of the loss was reduced by the relocation of some units back to Russia. The Russian Air Defence Forces ultimately inherited about 65% of final Soviet PVO assets. In December 1994, the 4th Independent Air Defence Army at Ekaterinberg in the Urals was transformed into the 5th Independent Air Defence Corps, which in 1998 became the 5th Air and Air Defence Forces Army. In accordance with a December 1994 directive, the 14th Independent Air Defence Army was reorganized as the 6th Independent Air Defence Corps (:ru:6-й_отдельный_корпус_ПВО) with the 16th Guards, 20th, and 94th Mukden Air Defence Divisions). In 1998, the force groupings and headquarters of the PVO that had remained within Russia were merged with the Russian Air Force becoming part of the Moscow District of Air and Air Defence Forces, and the 4th, 5th, 6th, 11th, and 14th Armies of VVS and PVO. The Day of Air Defence Forces (Den' Voysk PVO) was initially