A student-built model rocket lifts off during the Team America Rocketry Challenge on May 10. (credit: J. Foust)
The young rocketeer’s guide to range safety
by Jeff Foust
Tuesday, May 20, 2003
The launch started like any other that day. The public address announcer intoned the final seconds of the countdown: “Five, four, three, two, one, ignition!” There was silence for a few seconds, just long enough to make those of us standing nearby wonder if something had gone wrong. Just as those thoughts surfaced, though, the tail of the rocket belched smoke and flame, and an instant later we heard a distinctive whoosh as the rocket soared off the pad.
The scene, in this case, was not Cape Canaveral or Baikonur or Kourou, and the rocket was not an Atlas, Proton, or Ariane. Instead, this launch took place from a muddy field at a horseracing facility in rural northern Virginia, and the rocket was a small, spindly booster built by a team of high school students from Vermont. In this case the team of student rocketeers would share a similar, if humbling, experience with many professional rocket designers and engineers: a launch vehicle failure.
The problem took place as the first stage of the bright red rocket burned out. The rocket’s second stage was supposed to fire and send the rocket even higher, but the solid-propellant motor never ignited. The rocket continued higher on the momentum from the successful first-stage burn, but it soon peaked and started to fall. Worse, the second stage’s parachute failed to deploy.
“Watch out, people!” the announced warned. “It’s coming in ballistic!” The rocket was falling rapidly to earth, nose first, but where was it? We looked up, trying to locate the rocket, which had appeared to be heading in our general direction. The sky was cloudy, but the rocket was in the general vicinity of where the Sun was making a desperate, although eventually futile, effort to burn through the clouds. The result was a dull gray sky nearly too bright to look at, and nearly impossible to pick out the rocket from.
Luckily, a few people nearby had spotted it, and started stepping back. I turned and followed their lead. I had taken just a couple steps when I heard a dull thud behind me. I turned back and saw the rocket lying on the ground only a few meters away, just on the other side of a railing that marked the boundary of the spectators’ area. Within a minute the team of students that built and launched the rocket hovered over the scene, performing an ad hoc post mortem before recovering the pieces of the rocket. That turned out to be no easy task, as the nose cone had buried itself a dozen centimeters or more into the soft mud.
Fortunately, scenes like that were more the exception than the rule at the first Team America Rocketry Challenge. The one-day event took place Saturday, May 10 at Great Meadow, an equestrian center in The Plains, Virginia, about an hour west of Washington, DC. The event was billed as the largest model rocketry contest in the world as well as the first ever designed for high school students. Approximately 100 teams, from 36 states and the District of Columbia, participated in the contest, vying for $59,000 in prizes.
The contest rules were relatively straightforward, yet challenging. Each team had to build a rocket weighing no more than 1.5 kilograms. The rocket had to be built entirely by the student teams, with no assistance from teachers or other adults, and no use of model rocket kit components. (An exception was made for the rocket motors; commercial motors were required for safety’s sake.) Each rocket had to be able to fly to an altitude of 455 meters (1,500 feet): no more or less. The rockets also had to carry a fragile payload—two large, uncooked fresh eggs—and return it to the ground undamaged. Launches were scored by how close the rocket’s peak altitude came to 1,500 feet as well as how its payload survived the trip.
|Teams had to build rockets that could carry a payload of two eggs to 1,500 feet, and return them safety to the ground.|
The teams that competed at Great Meadow made it there by posting a qualifying score in local launch attempts. Once at the competition, though, they faced perhaps their biggest challenge: Mother Nature. The day of the contest started with a strong thunderstorm that delayed the start of the competition by over an hour. As a result, the teams, which has been placed into six groups, each with one-hour launch windows, were forced to compress their launch preparations into 45-minute windows. Even after the thunderstorm passed, rains continued for much of the day, although the launches continued except for a couple times in the afternoon when high winds briefly forced a halt to launch operations.
Most teams, though, managed to cope with the inclement conditions. Some used plastic bags and tarps to create makeshift covers for their rockets, keeping them from being exposed to the rain for as long as possible before launch. Others were apparently unaffected by the elements, preparing and launching their rockets as if it was a sunny, dry day. Some of the handful of rockets that failed may have been affected by the weather: team members speculated that the balsa wood used in some of the rockets may have absorbed water, affecting the trajectories of rockets or hindering staging events. Moreover, several days of rain leading up to the contest turned Great Meadow into something more like Great Mud Puddle: students who scampered across the terrain to recover their rockets often came back with their pants almost completely stained with mud.
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