Complex sentence: In the same year the very different Dart 2 variant appeared; this was a sesquiplane two seater with increased span, powered by a Anzani which was developed into the more powerful Driggs Skylark and Skylark 3 variants, both using versions of the Michigan Rover engine.
Split into simpler sentences: In the same year the very different Dart 2 variant appeared; this was a sesquiplane two seater with increased span, powered by a Anzani. This was developed into the more powerful Driggs Skylark and Skylark 3 variants, both using versions of the Michigan Rover engine.