Aboard a specially modified Boeing 727-200, G-FORCE ONE, weightlessness is achieved by doing aerobatic maneuvers known as parabolas. Specially trained pilots perform these aerobatic maneuvers which are not simulated in any way. ZERO-G passengers experience true weightlessness.

Before starting a parabola, G-FORCE ONEflies level to the horizon at an altitude of 24,000 feet. The pilots then begins to pull up, gradually increasing the angle of the aircraft to about 45 to the horizon reaching an altitude of 34,000 feet. During this pull-up, passengers will feel the pull of 1.8 Gs. Next the plane is pushed over to create the zero gravity segment of the parabola. For the next 20-30 seconds everything in the plane is weightless. Next a gentle pull-out is started which allows the flyers to stabilize on the aircraft floor. This maneuver is repeated 12-15 times, each taking about ten miles of airspace to perform.

In addition to achieving zero gravity, G-FORCE ONEalso flies a parabola designed to offer Lunar gravity (one sixth your weight)and Martian gravity (one third your weight). This is created by flying a larger arc over the top of the parabola.

G-FORCE ONEflies in a FAA designated airspace that is approximately 100 miles long and ten miles wide. Usually three to five parabolas are flown consecutively with short periods of level flight between each set.

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Zero Gravity Flight - Space Adventures