Moscow: Russia has started developing an air-droppable air defence missile system for its airborne forces, which is believed to be the world's first system of its kind, sources said on Wednesday. The system, code-named Ptitselov (Fowler), will be based on the BMD-4M Sadovnitsa (Lady Gardener) airborne armored assault vehicle, a source of the Russian defense ministry was quoted as saying. The tracked BMD-4M Sadovnitsa vehicle is fitted with the Bakhcha-U (Gourd Field) turret, comprising a 100-mm and a 30-mm caliber gun as well as a 7.62-mm machine gun, Xinhua news agency reported. The vehicle, commissioned in 2015, is meant to be used during raids behind the enemy's lines and is capable of reaching a speed of 70 km per hour. Currently, the main anti-aircraft battlefield assets of the Russian Airborne Forces are various modifications of the Strela-10 (Arrow-10) missile system, whose basic model was put into service in 1976.