before i can tell you about a split s..let me tell you about an Imelman (m-mel-man) turn.....the aircraft does a 1/2 inside loop..then rolls upright at the top of the 1/2 loop...the aircraft gains altitude and reverses direction..a split s is the reverse of an Imelman...the aircraft does an outside 1/2 loop and rolls wings level at the bottom of the 1/2 loop....the aircraft losses altitude and reverses direction..