The battle for the last scrap of land held by ISIS has taken longer than expected.
Russian Su-24 on a Bombing Mission
Russian air force bomber aircraft The Sukhoi Su-24 (NATO reporting name: Fencer) is a supersonic, all-weather attack aircraft developed in the Soviet Union. This variable-sweep wing, twin-engined side-by-side two-seater carried the USSR's first integrated digital navigation/attack system. It remains in service with former Soviet air forces and various air forces to which it was exported.