The Great Escape
There is no effective way to simulate weightlessness. Not under water in a pool, not suspended by a tether in midair and not free-falling from a skydive. However, Zero-G provides would-be astronauts, space tourists and adventure-seekers alike the chance to experience a variety of low and zero gravity environments that are as real as the laws of physics they defy. Such environments are exactly the same as those experienced in outer space—a true escape from the clutch of gravity.
While it’s rare, at least for adults, to defy anything at home, work or play, the Zero-G experience does afford one a chance to defy gravity and laugh in Sir Isaac Newton’s face while slipping the surly bonds of Earth’s gravitational pull. Unfortunately, the joke is ultimately on us because this act of defiance is fleeting—only about 30 seconds—before the laws of physics are strictly enforced. At which point, at the end of each maneuver (called a parabola), Zero-G passengers are dealt a heavy-handed reminder—nearly two g’s—that gravity can be trifled with but cannot be conquered on Earth.
The Aircraft—Boeing 727-200 (aka G-Force One)
The Boeing 727 was selected as the Zero-G platform because of the highly swept wing (35 degrees) and T-tail. A highly swept wing is necessary for high-speed flight—exactly why Gulfstream wings are swept so acutely. And the flight profile of the Zero-G parabola in the 727 approaches the published high-speed limit of the airframe (Vne Mach 0.87).
The T-tail, with its inherent safety benefits, was also a key consideration for the perfect Zero-G platform. One of the safety characteristics of the T-tail design is the fact that locating the horizontal stabilizer and elevator high on the swept vertical stabilizer ensures that the articulating flight control surfaces remain in clean (undisturbed) air at all times and in all phases of flight. Meaning that there is never any turbulent air flowing over the elevator so the pilot always has full and positive control authority. And if a 35-degree swept wing and T-tail configuration sound familiar, it may be because the ultrahigh-speed (Mach 0.925) Gulfstream G650ER, G650, G600 and G500 all have similar 36-degree swept wings and a T-tail for high-speed maneuverability.
Unfortunately, the joke is ultimately on us because this act of defiance is fleeting—only about 30 seconds—before the laws of physics are strictly enforced.
Amazingly, modifications to convert a standard Boeing 727-200 to G-Force One were minor. The hydraulic systems have been altered to prevent cavitation from an errant air bubble resulting from unusual pitch attitudes. An accelero-meter was also added in the cockpit to help the pilot, hand-flying the aircraft, execute the specific profiles necessary to achieve lunar and Martian gravity in addition to zero gravity.
The cabin is divided into four areas of equal size. The rear of the cabin has 38 standard-issue airline seats. The balance of the cabin has been stripped clean and reassembled as a fully padded tube from floor to ceiling. Three areas on the cabin floor (outlined by blue, gold or silver tape) designate where passenger groups have been assigned to perform astrogymnastics.
In addition to all of the FAA-required maintenance and inspections for normal Part 121 operators, G-Force One gets visual wing spar inspections before and after every flight.
The Profile—The Parabola (aka a Sine of the Times)
Seen from the side, the mission profile looks like a basic sine curve with the aircraft flying a series of steep climbs to gain altitude followed by a dive to create the desired gravitational scenario. Naturally, this mission requires a significant block of airspace for maneuvering.
The FAA accommodates the request by creating what is akin to a Class A airspace aerobatic box that extends between 19,000 feet and 32,000 feet that is 10 nautical miles wide and 100 nautical miles long. Upon entering the designated airspace at the assigned ceiling, the aircraft is placed into a gentle dive. Using the accelerometer, the pilot pitches the aircraft for the desired affect to create Martian (0.375 g), lunar (0.165 g) or zero gravity.
In anticipation of reaching the floor of the designated airspace, the flight crew notifies the flight director in the cabin to call out “feet down, coming out.” This announcement is the command for all passengers to lie prostrate on the floor as the pilot arrests the dive and stabilizes the aircraft before pitching up 45 degrees to begin another parabola.
The Experience—Zero Gravity (aka Weight for it)
Describing the experience of being weightless has always been a challenge for the team at Zero-G. How does one describe something in relative terms to a person who has no frame of reference? For example, imagine attempting to describe a sunset to a sightless person. Thankfully, the vast majority, if not all people reading Nonstop, have experienced the miracle of flight—and perhaps even brief moments of higher g’s upon takeoff or lower g’s in turbulence. With that experience as the relative frame of reference, the following may help illustrate the Zero-G experience that consists of one Martian parabola, two lunar parabolas and up to 12 zero gravity cycles.
To ease into the experience of zero gravity, the Zero-G flight crew begins the flight sequence with a parabola that produces Martian gravity. This fairly benign maneuver provides the first sensation of reduced gravity.
Martian gravity is 0.375 g—roughly one third of that felt on Earth. On Mars, a 200-pound person would weigh 76 pounds. To get a sense of how this feels, passengers rise to their feet, where their assigned Zero-G coach encourages them to bounce up and down as if doing squat thrusts. Witnessing other people performing the same exercise seems more like watching a slow-motion video than witnessing this in real time. Every action has predictable results. As you jump in the air, you return gently back to the floor where you started. No surprises, just a seemingly slow-motion activity that builds anticipation and excitement as gravity begins to loosen her grip.
Leaving Martian gravity behind, the aircraft is pulled out of the dive to be pitched up again to gain altitude. The transition at the bottom of the parabola exposes passengers to 1.8 g’s. Meaning that for a few brief moments, a 200-pound person weighs 360 pounds.
The next two parabolas are to lunar gravity. On the moon, the gravitational pull is reduced to 0.165 g. The same 200-pound person now only weighs 34 pounds. If the cabin of G-Force One were empty, the first NASA moonwalk could easily be reproduced. Moving in this low-gravity environment combines interim moments of near-weightlessness with the predictability of the effects of gravity. For example, if you leap forward, you soon realize that you’ll land along the same path that your trajectory began.
The near-weightless environment also allows people to jump in the air, perform a basic gymnastic stunt (somersault, pike, twist, tuck, etc.) and land in place without any special skill, thanks to the slowed reaction of the force of only 0.165 g’s.
Trying to describe the sensation of weightlessness to a person who has never left the Earth is akin to describing the sunset to someone who has never seen a color.
With one Martian and two lunar parabolas complete, the main event begins on the fourth parabola. The first zero-gravity cycle is a spiritual experience—some even find it a bit unsettling at first. This is where words become woefully inadequate to illustrate the experience. Again, trying to describe the sensation of weightlessness to a person who has never left the Earth is akin to describing the sunset to someone who has never seen a color.
Being truly weightless for the first time feels as if the imperfections of our humanness that bind us to Earth and separate us from the heavens above have been washed away as you gradually become free of Earth’s grasp and float in inner space.
Upon completing the first weightless parabola, the G-Force One cabin erupts in cheers after responding to the command “feet down, coming out.” While this first weightless experience is one that will alter your being forever, it passes in a flash—almost faster than you can process what you’ve just experienced. The good news is there are 11 more parabolas to follow.
As each subsequent parabola is anticipated, you’ll try to think about what new and exciting maneuver you can attempt to execute during your next 30 seconds in space. Standing on the ceiling, catching floating globules of water hanging in midair above or below you, or spinning perpetually in a tuck while hovering above the floor. In the absence of gravity, only the slightest push-off from any surface has the potential to propel one indefinitely. Fortunately, in the safety of G-Force One, there is no risk of floating off into space untethered.
In aviation circles, it is fairly common to partially quote the first line of Royal Canadian Air Force Pilot Officer John Gillespie Magee Jr.’s 1941 poem “High Flight” to capture the romantic essence of flight. Yes, those of us who have experienced the realm of flight have indeed “slipped the surly bonds of earth.” But the surreal experience of experiencing weightlessness is, if only temporarily—boundless.
G-Force One has a busy schedule that includes contracted flights to conduct research in low gravity and weightless environments plus commercial flights to introduce people to a world without gravity. To book a seat, visit GoZeroG.com. If you really want to lighten your wallet, G-Force One can also be chartered for private use for US$165,000 plus tax. Unless you’re flying your Gulfstream to a location for the Zero-G flight, there may also be fees to reposition G-Force One to a location of your choice. But if you want to provide your family a unique experience of a lifetime or are interested in creating an amazing work incentive or reward, the Zero-G experience is truly out of this world. And there is of course a frequent floater program.
Downside Up—a NASA Tradition
During your Zero-G flight, you’ll be part of a tradition that is said to have originated with NASA astronauts. As you board the aircraft for your first flight, the name badge on your flight suit will be upside down.
Granted, in most circumstances, that may seem odd. But in a zero-gravity environment with no view of the horizon, it can sometimes be difficult to discern what is up and what is down, so an inverted name badge doesn’t really offend your sensibilities. But here’s a trick you learn quickly: If you look at the seats in the rear of the cabin and they appear to be bolted to the ceiling, you’re upside down.
Once back on the ground as your feet touch the tarmac, a brief ceremony takes place under the tail of the aircraft to flip your name badge, indicating to the world that you are now among an elite cadre of people—gravity-defiant ones.
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