Complex sentence: The Columbia 300 was upgraded with a glass cockpit and other improvements from the turbocharged Columbia 400, certified on March 30,2003 as the Model LC42-550FG and marketed as the Columbia 350.
Split into simpler sentences: The Columbia 300 was upgraded with a glass cockpit and other improvements developed for the turbocharged Columbia 400. It was certified on March 30,2003 as the Model LC42-550FG and marketed as the Columbia 350.