Complex sentence: In July 2013, the Air Force began a fleet-wide technological upgrade of its B-52 bombers called Combat Network Communications Technology (CONECT) to modernize electronics, communications technology, computing, and avionics in the cockpit.
Split into simpler sentences: In July 2013, the air force began a fleet-wide technological upgrade of its B-52 bombers. The modernization efforts increase the electronics, communications technology, computing, and avionics in the cockpit.