Chapter One: Ups and Downs "Check it out, Sandy," I said, looking at my younger sister upside down. Like a spider, I used my fingers and feet to slowly "walk" across the padded surface of the plane's ceiling and then back again. "I've always wanted to be a 'fly on the wall'!"
Sandy looked up at me. She was hovering in a cross-legged sitting position a good six inches off the plane's floor. "Ho, ho, ho, it's Tom Swift Jr., the king of comedy," she replied into her Swift Speak, the miniature microphone-and-earpiece combo that allowed us to communicate in normal voices over the roar of the plane's engines. "Just don't fall on me when the plane finishes its arc!"
We were passengers aboard the SwiftStar,, the latest invention of my dad's business, Swift Enterprises. It was a special jet astronauts used to get a feel for what it would be like to be in outer space, where there was very little gravity. Microgravity, it was called. Scientists used the plane too; some of their experiments work best in a weightless environment.
My dad showed Sandy and me the plans for the plane months ago, and it didn't take long for me to become as excited about it as he was. "The plane's the size of a small air tanker," he explained, pointing to diagrams on the paper. "It'll make a steep, graceful climb to a high altitude, then descend in that same arc."
Sandy nodded. "Coming down, the people inside will become weightless!"
"You got it, Sandy," Dad said, squeezing her shoulder. "But only for about a minute."
"A minute?!" I repeated, unable to believe my ears. "That's more than twice the time you can float in a 'Vomit Comet'!"
My dad was too caught up in the excitement of the project to realize I had called the plane that the air force and NASA used for the same purpose by the nickname they used. "And the 'Vom...'" He paused, catching himself. He cleared his throat and scratched his graying temple. "The plane the government uses can only make thirty to forty parabolas," he said, dipping his hand up and down to mimic the plane's flight path. "The SwiftStar, has increased fuel capacity, so it can stay in the air for six hours!"
"Twice the ups and downs, twice the training!" I said, shaking my head.
"And twice the science," Sandy added.
"Sweet!" I exclaimed.
"Sweet, indeed," Dad said, nodding firmly.
Suddenly, my arms and legs felt as heavy as oak tree logs -- gravity was coming back. Captain Lisa Ryder's voice crackled over the plane's intercom. She was Swift Enterprises' chief test pilot. "How's my honorary crew?" she shouted above the engines' roar, and I could tell from the way she said it that she was smiling. "Anybody need an airsickness bag?"
"No problems back here, Lisa, we're floating like feathers," I answered lightly...then bumped my head against the fuselage. Good thing the main cabin of the plane was heavily padded. For takeoffs and landings, we'd be strapped in to the traditional airplane seats that were in the rear cabin. And they were safely bolted down.
A member of the SwiftStar,'s real crew smiled at Sandy and me. He was there in case one of us got hurt, or sick. "Feet down, coming out," he yelled.
I stretched out my legs and grabbed on to a padded handle on the side of the fuselage. My feet lightly touched the floor, then slowly gained more and more weight. Even though I'd only been weightless for less than a minute, it felt like a sumo wrestler was pressing down on the top of my shoulders. All of a sudden I found myself missing that free-floating sensation and I couldn't wait for that feeling again. Once you'd had the chance to fly, it was hard to give it up, even for a little while.
Sandy, too, drifted down to the floor of the plane, her legs still crossed in a sitting position. She grasped handles set into the floor on either side of her. "What's the deal?" I asked her. "You just sat when we went zero-G! Why weren't you bouncing around and having fun?"
"I was studying," she answered patiently, "trying to figure out the most efficient ways to move." That's my little sister, more into the science than the coolness. A real firecracker.
The plane started to climb again into another arc, and I felt my full weight return -- and then increase. We were climbing at an angle of forty-five degrees, so steep, I felt almost twice as heavy as usual, to the point where it was even hard to hold myself up.
"Ready for float," the crewman shouted after half a minute, and the SwiftStar, leveled out, then dipped toward the ground again. All sense of weight disappeared, and my toes lifted off the floor once more into the total freedom of weightlessness. I let go of the handle and let myself drift, as though in a lake on a lazy summer afternoon.
I watched as Sandy rose off the floor in her sitting position, then unfolded her legs and reached up for one of the handles lining the walls. She tested her grip for a second, then pulled herself past the handle, her momentum propelling her forward until she reached the next handle, and the one after that, and the one after that. She "swung" the length of the cabin and back faster than I could have walked! She took a handle across the cabin from me when she got back. "That seemed pretty efficient, didn't it?" she asked.
I had to try it myself. If Sandy could do it...I stretched out parallel to the floor, still holding the handle. I took a deep breath, then pulled myself forward and pushed off, moving far faster than Sandy had been going. Unfortunately, I was going too fast, and missed the next handle, swiping at it in vain. I flailed my arms like a drowning man, and tumbled end over end the length of the cabin before thumping into the padding at its end. I bounced off and hung in the air upside down, dazed. "Sure didn't feel efficient," I muttered sheepishly.
"You've gotta take your time," Sandy called out to me, pointing to her belly button. "Make sure your line of motion runs through your center of gravity at all times, and just go handle to handle and don't worry about speed.... That'll take care of itself!"
I decided to try it her way, took another deep breath, and reached for the closest handle. Wouldn't you know, I made it back to my starting point without breaking any bones or looking too stupid. "Pretty cool," I admitted. "That'll make getting around a lot easier on our vacation!"
The crewmember raised an eyebrow. "You're going on holiday in the SwiftStar,?" he asked loudly.
"Even better," I shouted back excitedly. I could feel the weight returning to my arms and legs -- and I could feel myself wanting to be back in microgravity as soon as possible. "We're going on vacation two hundred and thirty-six thousand miles from Earth!"
Copyright © 2006 by Simon & Schuster, Inc.
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