Complex sentence: Both Mikoyan and Sukhoi submitted concepts to the Defense Ministry for the PAK FA program (MiG entering an updated Project 1.44), but the Russian Defense Ministry selected the Sukhoi Design Bureau as the primary contractor for the PAK FA fighter.
Split into simpler sentences: Both Mikoyan and Sukhoi submitted concepts to the Defense Ministry for the PAK FA program (MiG entering an updated Project 1.44). The Russian Defense Ministry selected the Sukhoi Design Bureau as the primary contractor for the PAK FA fighter.