Complex sentence: The S-35 was a sesquiplane with a fixed tailskid landing gear, it was modified to take three Gnome-Rhône Jupiter 9A radial engines, these modifications took time to complete and the aircraft first flew on 23 August 1926 from Roosevelt Field.
Split into simpler sentences: The S-35 was a sesquiplane with a fixed tailskid landing gear. These modifications took time to complete and the aircraft first flew on 23 August 1926 from Roosevelt Field.