The process starts with the aircraft flying level with the horizon at an altitude of 24,000 feet. The pilots then gradually increase the angle of the aircraft to about 45° relative to the horizon until reaching an altitude of 32,000 feet.
During this phase, passengers feel the pull of 1.8 Gs. Next, the plane pushes over the top of the parabolic arc and the zerogravity phase begins. For the next 20-30 seconds, everything in the plane is weightless.
Finally, the plane gently pulls out of the maneuver, allowing flyers to gradually return to the floor of the aircraft.