Reza Nakhjavani, head of Iran’s Civil Aviation Organisation has said the country has replaced its Russian Topolev aircraft after the manufacturer withheld the requested reports on the crash of its airplanes in Iran, Fars news agency has reported. “The investigation report into the main cause of the crash of the Topolev passenger plane of the Caspian Airline was finalised by Iran’s Civil Aviation Organisation and was reflected to the Russians but the Russian manufacturing company and the country’s Aviation Organisation refrained to provide a response in this regard,” Nakhjavani told the news service.