The Israeli Air Force is changing its pilot training, giving new pilots centrifuge training earlier in their careers. The centrifuge device whips pilots around in a circular motion at high speed, which recreates the effects of high speed turns. This sort of thing puts high G (Gravity) force on the pilot, which is disorienting, and can even cause black outs.
The immediate reason for the training change was the recent death of a pilot during an air combat exercise. This bit of training involved some "dog fighting" (lots of sharp turns) and the pilot was believed to have suffered G force disorientation, which led to the accident that killed him.