 The primary role was long range air defence against American SAC B-1B and B-52G/H bombers, protecting the Soviet coast from aircraft carriers and flying long range fighter escort for Soviet heavy bombers such as the Tu-95 "Bear", Tu-22M "Backfire" and Tu-160 "Blackjack".There are several related developments of the Su-27 design.The Su-30 is a two-seat, dual-role fighter for all-weather, air-to-air and air-to-surface deep interdiction missions.