It was a cool, overcast March morning high above the Gulf of Mexico, and Noel Nutting and Dan Barnett, senior mechanical engineering majors at UVM, were experiencing the adrenaline rush of big adventure. The pair was moments away from achieving weightlessness aboard NASA’s KC-135A aircraft, colorfully (and accurately) nicknamed “The Vomit Comet,” and they had to concentrate to control the nervous excitement that seemed to fill them with a jumpy energy.

The plane was at thirty-thousand feet and climbing steeply. Nutting and Barnett were among two dozen college students, journalists and NASA administrators — all participants in NASA’s Reduced Gravity Student Flight Opportunities Program — plastered to the padded floor of the aircraft, held there by two g’s worth of downward force that made their limbs feel like dead weights. Then it happened: the downward force lessened, then lessened more, until finally there was nothing holding them down. They popped up off the floor and floated about the cabin as if moving through very thin water.

Barnett and Nutting, like all the students onboard, had an experiment to monitor, but the first moments of weightlessness were so strange and wonderful that it was near impossible to concentrate on anything else. Sporting huge grins, the pair bounced off the ceiling and turned somersaults. After twenty seconds of mid-air frolic, a NASA spotter suddenly yelled “Feet down!,” and everyone got to the floor, fast; the zero-gravity period ended in seconds, and anyone caught on the plane’s ceiling faced a hard fall if they didn’t get down. A minute later, after another two-g climb, everyone was floating again, whooping and laughing as they kicked and twisted in mid-air.

For Barnett and Nutting and their UVM teammates, the month and a half leading up to this moment had been intense and hectic, and the weightlessness seemed to bring with it an immense relief. Barnett, suspended between the plane’s floor and ceiling, summed up the experience in a succinct exclamation: “This is awesome!”

A few moments of awesomeness in the skies above NASA’s Houston headquarters were the final, fleeting rewards for a great deal of hard work by Nutting, Barnett, and fellow mechanical engineering seniors Dan Cheung and Megan Carroll.

The road to Houston began last fall with a special projects course taught by Tony Keller, associate professor of mechanical engineering, and Mark Miller, a doctoral candidate in mechanical engineering. Miller had received a $34,000 NASA grant in 1997 to study the effects of weightlessness on fruit flies, part of his research on the links between metabolism and aging. Weightlessness would be achieved by launching the flies — along with a host of complex monitoring equipment — in a Nike-Orion sounding rocket fired at NASA’s Wallops Island facility in Virginia. (The launch is slated for July.) The experiment would be transported in the rocket’s nose cone and would subject the flies — drosophila melanogaster — to about five minutes of weightlessness before falling back to Earth. Miller, consequently, needed to design a strong, well-organized experiment to house the flies and record their activity in zero-gravity — a perfect project, he concluded, for undergraduate engineers.

Miller and Keller offered a special projects course for senior engineering majors in the fall of 1997 to design the experiment, and continued the course for a new crop of seniors — including Nutting, Carroll, Barnett and Cheung — last fall. Midway through the semester, Keller urged the students to submit a proposal for the yet-to-be-completed experiment to NASA’s competitive Reduced Gravity Student Flight Opportunities Program, a two-week program that lets teams of undergraduates from colleges around the country conduct scientific experiments in zero-gravity aboard the KC-135A. The proposal was accepted in late December for the March program, which meant that the ante for the project had been upped considerably: not only did the students have to complete the design of the experiment, but they also had to build it from scratch, all in a scant six weeks.

That meant creating enclosures for the flies, devising complex electronics to monitor the flies’ movements and store the data, adding heating and cooling systems to ensure a consistent environment, rigging up lighting and providing an on-board power supply — all of which had to fit in the very vertical, very narrow space of a nose cone, and be able to withstand the tremendous g-forces of a rocket launch. The students returned for the spring semester and dove into the project.

The ten students in the special projects class hurriedly completed the design work, and Nutting, Barnett, Cheung and Carroll, with plenty of help from Miller, Keller and other students in the class, oversaw the fabrication of the experiment in the department’s design shop. They hired a Williston company, SolutioNet, to design some of the complex electronic components, and worked round-the-clock to complete the project in the final days before leaving for Houston.

“There were too many anxious moments to count,” said Nutting, of Essex Junction, Vt., recalling the race to finish the project. “We hardly slept or ate that last week — we were in the shop constantly.” Cheung, from Roslyn Heights, N.Y., said the process was slowed by time-consuming — but essential — trial-and-error. “The design for the fly chambers was always changing,” he said. “You’d spend ten hours working in the shop only to realize that what you’d just made wouldn’t work and that it had to be completely redesigned.”

Final approval on design and fabrication had to come from Keller, whom Carroll, of Vineyard Haven, Mass., credited with the rocket’s extremely well-made elegance. “He’s a total perfectionist,” she said. “One of his rules was, ‘No duct tape.’”

By the end of the first week of March, days before the start of the two-week NASA program, the essential structure of the experiment — a four-foot-tall, multi-level tower of CNC’ed aluminum and Plexiglas — had been completed, and the students were tending vials of newly hatched fruit flies. But the tower’s costly and complex electronics, which Miller would bring with him to Houston several days after the students arrived, had yet to be installed and tested; the heating and cooling systems were not yet functioning; lighting had yet to be added; and trial runs had to happen before the tower was hoisted into the aircraft for its maiden voyage.

On March 6, the students carefully packed the tower — sans duct tape — in the back of a rented van and prepared for the two-day drive to Texas. They were heading for Houston at last, but all systems were definitely not go.

NASA’s Ellington Field, located a few miles north of the Johnson Space Center, sits amid the vast suburban sprawl of southeast Houston. Nimble T-38 training jets perform improbable maneuvers above the field, filling the skies over subdivisions with the whine of maxed-out engines.

Ellington’s dominant feature, Building 990, is a cavernous hangar used for aircraft storage and maintenance, and was the destination of the UVM foursome, who rolled in on schedule on March 8. The students unloaded the tower, as well as an assortment of tools and gear, and set up shop on a work table in the middle of the bustling hangar, which would be ground zero for twenty-two undergraduate teams for the next two weeks.

The students settled into their rooms at a nearby motel and awaited the arrival of Miller and Keller. Each of the rooms was a study in contrasts: typical spring break accoutrements like backpacks, sandals and coolers mingled with tool kits, volt meters, spools of wire and bits of electronics. In one of the rooms, glass vials teeming with fruit flies covered the bathroom countertop, while drosophila that had escaped their confines buzzed lazily above the sink or crawled amid the bristles of scattered toothbrushes. Evenings that first week were spent noshing Tex-Mex at a nearby Taco Cabana restaurant, duking it out at a local go-kart track or hanging out at the motel watching the NCAA basketball tournament on TV.

Days, though, were devoted to working on the tower and running a gauntlet of NASA activities. There was an exhausting, all-day KC-135A safety training class, which included detailed instructions in the use of airsickness bags (“Stuff floats up there, guys, and then it lands, and then it’s a big mess,” one instructor cautioned, “so really clamp those bags tight to your face”) and culminated with a session in a hypobaric chamber, a device that produces the dizzying and disorienting effects of being without supplemental oxygen at twenty-five thousand feet. There were tours of the Johnson Space Center, barbecue shindigs and impassioned talks by astronauts, who did their best to convince students that manned space flight, far from being a Cold War holdover, will be a key component of scientific exploration in the next century.

At the end of the first week, the UVM experiment had to pass a Test Readiness Review (TRR), a rite-of-passage conducted by zero-gravity program administrators and KC pilots who pronounced experiments fit — or unfit — to fly. There was a crackle of nervous tension in the Ellington hangar as the officials moved from project to project, asking questions and taking notes.

“Cheung,” said Nutting. “You nervous?”

“Naw,” said Cheung, who would lead UVM’s presentation. “It’s no big deal.”

“Yeah,” said Nutting, relaxing. “We know this thing by heart.”

The reviewers finally circled the UVM project, and Cheung gave them an overview of the experiment and how it was constructed. Most of the reviewers studied the tower, nodding slowly, and a couple of them raised safety questions about exposed wingnuts and the sharp corners of an auxiliary power supply. After assurances by the students that the protrusions would be padded, the tower was approved, and everyone breathed a little easier.

When the TRR’s were complete, John Yaniec, test director for the KC-135A and lead reviewer, was surprised to learn the UVM students had built the project themselves — he thought they had borrowed a sophisticated piece of gear from somewhere to run their fruit fly experiment. “This is typical of the kind of hardware we see from the NASA researchers,” Yaniec said, impressed. “[The KC-135A flight] will be a great way for them to fine-tune the experiment and ensure a better chance of success with the Nike-Orion launch.”

Then there was the matter of who would fly when. The program is designed so that each experiment flies twice, accompanied by two students per flight. UVM only had three flyers, however — Carroll, in a preliminary NASA physical exam, had mentioned a bout of exercise-induced asthma that she experienced in high school, and program officials, despite repeated pleas from the students, refused to let her fly as a result — which meant one student could fly twice. Nutting bowed out, saying one flight would probably be enough, so Barnett and Cheung settled the matter one night over dinner with a rock-scissors-paper face-off, best two-out-of-three. They waved their fists over a plate of Cajun crab legs: Barnett’s paper covered Cheung’s rock, and his scissors cut Cheung’s paper. Barnett, of Asbury, N.J., would fly twice.

Barnett’s succinct exclamation: “Awesome!”

Miller arrived in Houston near the end of the first week, and the tower was relocated from Ellington to the motel so that he could spend most of his waking hours laboring over it. The amiable Miller, 29, an Iowa native with an aerospace engineering degree from the University of Colorado, took up residence on the floor of his motel room and painstakingly installed the experiment’s missing electronics. He fiddled with the tower’s problematic heating and cooling system, designed to keep the flies at a consistent 25 degrees C. He sat and stared at the tower, the culmination, to date, of his doctoral work, then tinkered with it some more. Still it refused to work properly.

By the end of the weekend the strain of all the fine-tuning, and the painful slowness with which progress was achieved, had begun to wear on the group. Miller and the students were spending hours each day fiddling with the tower’s numerous details, and the energy that had buoyed them earlier in the week had dwindled markedly. There were moments when the students would simply sit and stare silently at the tower, the unspoken worry being that they might have to fly with a malfunctioning experiment. Miller, surrounded by an array of electronic gadgets, continued to fine-tune, even when a system appeared to at last be working properly. “Mark can tinker forever,” Carroll muttered at one point, rolling her eyes. It was with great relief that the students packed the van early the second week for a two-day respite on the broad beaches near Corpus Christi, three hours south of Houston.

The students arrived back in Houston on Wednesday, tanned, rested, and ready for the final push that would culminate in the first of two flights on Friday morning. Miller, in their absence, had managed to tweak the tower’s electronics sufficiently so that all systems appeared ready to go. After another late night of jiggering the final details, the tower, along with a half-dozen other student experiments, was finally loaded aboard the KC-135A on Thursday in preparation for its flight the following day. There was nothing left to do but load the tiny fruit flies into their trays and hope for good flying weather.

But the skies over Ellington Friday morning were dark and menacing; a massive bank of slow-moving thunderstorms was stalled over the region. KC-135A pilots conferred while the morning’s student fliers, decked out in olive drab NASA flight suits, crowded into an Ellington conference room, anxiously awaiting the verdict. When it came, it was terse and disappointing: no flight today. That meant that, weather permitting, there would be two flights on Saturday. No one wanted to speculate what might happen if the weather was bad again Saturday — that students from seven schools, including UVM, might have to go home without flying. “Let’s assume we’ll get everybody up tomorrow,” the pilots kept saying.

But the capricious weather gods of East Texas smiled: Saturday dawned cool and breezy with a high overcast, which meant the day’s flights would go as planned. At 9:30 a.m. Barnett and Nutting, along with a couple hundred fruit flies stowed in the tower, took off aboard the KC-135A while the rest of the team watched a live video feed of the flight amid the high-tech clutter of Building 990.

After a short trip out over the Gulf of Mexico, Nutting, Barnett and a dozen other students checked their experiments — most were bolted to the floor of the airplane — one last time and prepared for weightlessness. The aircraft, a converted tanker similar to a commercial Boeing 707, creates zero-gravity in the open, padded cabin by flying a series of steep, rolling arcs between twenty-five thousand and thirty-five thousand feet; zero-g conditions exist for about twenty seconds at the top of each arc before the airplane plunges downward and begins another stomach-wrenching two-g climb. Each two-and-a-half-hour flight includes forty zero-g arcs, as well as an arc that simulates lunar gravity and one that simulates Martian gravity.
Down in the hangar, Miller, Keller, Carroll and Cheung, along with students from several other schools, watched the video feed, transfixed, as the flyers bounced and somersaulted and cavorted. “I can’t wait to get up there,” said Cheung, who would fly the afternoon trip with Barnett. “That looks so cool.”

The team met the flyers on the tarmac when the plane landed. Barnett, all smiles, looked fresh and ready to go up again, but Nutting looked a bit pale after a couple bouts of motion sickness. (Nausea is a problem that, despite widespread use of motion-sickness medication, affects about half the people who fly the KC-135A.) “It was a little rough on the old tummy,” Nutting said, walking gingerly toward the hangar. “But it was still definitely worth it — it’s the wildest rollercoaster ride I’ve ever been on.”

A couple hours later, after a quick lunch and yet more onboard tinkering with the experiment — it had run too cool during the morning flight, possibly limiting the flies’ activity — Barnett and Cheung took off on UVM’s second weightless adventure. Twenty minutes or so into the flight they were given the okay to leave their seats and prepare for the first series of arcs. They checked the experiment’s temperature, which the between-flight tinkering seemed to have fixed. “One minute!” the spotter called out, preparing the fliers for the climb. The climb topped out and the zero-g period began, and Cheung whooped as he began floating “What an amazing feeling!” he exclaimed.

Cheung and Barnett spent the first several arcs explaining the experiment for a NASA videographer as they floated gracefully above the tower, then engaged in a few zero-g high jinks, like using a squirt bottle to shoot wobbly little blobs of water across the cabin into each other’s mouths. “This is a weird sensation!” Cheung said a few arcs later, before he, like Nutting, succumbed to motion sickness, while Barnett continued to cavort, arc after arc.
The flight, like the morning trip, passed in a blur, and soon the students were on the ground again, turning in their flight suits, removing the tower and its flies from the airplane. A few hours later, the students discussed the flights with Miller and Keller over dinner. The data had yet to be collected from the experiment, but Miller was already optimistic. “The experiment and the students both performed really well,” he concluded. “I don’t see how this could have gone any better.”

The team’s final dinner together in Houston wound down as the students prepared to leave for Vermont that evening, but there was one more piece of business: figuring out who won the pool for guessing what arc each flyer would get sick on. After a quick tally, the winners were Keller and, appropriately, Barnett, whose double-flight exploits had earned him the title “Iron Dan.”

“Awesome!” Barnett exclaimed as his teammates ponied up. “The flights were cool, but this really makes it worthwhile.”

Back in Vermont, Miller described his initial examination of the experiment’s data as “very encouraging.” Acceleration and temperature data of the second flight provided him with an accurate picture of the flies’ environment, and data gathered using infrared beams indicated that the flies were much more active when they were weightless. “Among the normal flies, there was a huge jump in activity — the females had an 800 percent increase, and the males had almost 400 percent,” Miller said. “That second flight had a temperature spike, though, where the temperature inside the tower went from 23 degrees C to 26 degrees C. We need to get some baseline data at 26 degrees C to determine how much of the flies’ activity was due to zero-gravity and how much was due to the temperature increase.” Miller expects to have all the data analyzed by the end of the summer.

By that time, the tower — stocked with new generations of pioneering drosophila — will have been weightless two more times. The Nike-Orion sounding rocket launch is scheduled for mid-July, and Nutting and Cheung are helping Miller prepare the tower. In August, another quartet of UVM students will accompany the tower aboard the KC-135A as part of the Reduced Gravity Student Flight Opportunities Program.

In the near future, Miller envisions the tower flying aboard the space shuttle, and a bit further down the road he’d like to see it aboard the International Space Station for a prolonged period of zero-gravity — all achieved with the help of UVM undergraduates. “The idea is to keep this moving forward as a space flight experiment, using it for ground-based research, establishing a lot of baseline data, then using that to go after bigger programs like the shuttle and the space station,” he said. “I’d like to see it continue to be an undergraduate project. This is the kind of project that really gets students interested in engineering — you get so much confidence by flying something that you’ve designed and built yourself. I think what the students have accomplished so far has been pretty impressive, so why not keep going with a good thing?”