Split S

The Split S consists of a half roll (which turns your plane upside down) and a half loop (so your plane turns right side up and faces the opposite direction). Executing this maneuver takes your plane through a slow half roll followed by a sharp nosedive into a half loop. Your plane will exit the maneuver at maximum speed.

It is essentially the opposite of a Immelman, which is a half loop followed by a half roll.