a sidewinder starts like the first half of a traditional vertical loop. When the train is near the loop's apex it will be inverted and heading back in the direction it entered. Rather than completing the loop in the traditional way, the train rolls on its axis becoming right-side-up while simultaneously turning away from the loop. The result is the train exiting the maneuver almost nearly 90° to the right or left of direction it was entered. This is a very similar element to the Immelman. In the case of the Immelmann the after apex turn is not as sharp and the maneuver is exited lower and nearly in the direction it was entered.