A Lycoming IO-540-T4B5 fuel injected, air-cooled, six cylinder, normally aspirated engine rated for 260 HP at 2,700 RPM powers the 115 and 115AT, and a Lycoming TIO-540-AG1A turbocharged engine rated for 270 HP at 2,575 RPM powers the 115TC. The engine is equipped with dual magnetos with gear-driven independent drives, shielded harness assemblies, radio shielded spark plugs, and two independent vacuum pumps. TBO is 2000 hours for either engine. The cowl is easily removed for quick access to the engine compartment for routine maintenance.