http://www.flightglobal.com/article...itary-an-22-crash-sparks-fleet-grounding.html Russian authorities have grounded Antonov An-22 and Tupolev Tu-95 aircraft following the crash of an An-22 during a training flight. The giant four-engined transport aircraft came down near Troitskoye in the Tula region, in the southwest of the country. Russia's defence ministry, in a statement, says the radar marker of the aircraft "disappeared from screens" at 21:30 Moscow time on 28 December. Two search teams were dispatched to the point of impact and a cordon established, it adds. Rescue efforts have been complicated by poor weather conditions. The defence ministry states that, in order to ensure safety, it is grounding aircraft types with similar engines - such as other An-22s as well as the Tu-95. Flights have been "suspended" by the head of the Russian air force until the reason for the accident is determined, says the ministry. An-22 aircraft were designed to be powered by the Kuznetsov NK-12 turboprop, with contra-rotating propellers. Around 12 occupants were reportedly on board the aircraft, said to have been en route to the Migalovo military base in the western Tver province, and there is no indication of any survivors. The defence ministry has set up a commission of inquiry.