Hybrid planes are moving closer to takeoff. At the EAA AirVenture Oshkosh airshow Tuesday, GE Aviation said it signed a deal with XTI Aircraft Company to use GE’s Catalyst engine as the core of a new hybrid-electric propulsion system for a planned XTI business aircraft, the TriFan 600. It’s the first step in what GE Aviation expects will be a journey that hopes to bring a new, differentiating product to the business and general aviation market.