A ROCKET BUILT BY STUDENTS REACHED SPACE FOR THE FIRST
TIME
A USC team won the collegiate space race by
sending a rocket above the Kármán line, the imaginary boundary that marks the
end of Earth's atmosphere.
IN THE EARLY morning of April 21, 10
students from the University of Southern California's Rocket Propulsion Lab
piled into the back of a pickup truck with a 13-foot rocket wedged between them
and drove down a dusty dirt road to a launchpad near Spaceport America, in
southern New Mexico. When they arrived, their teammates helped them lift the
300-pound rocket onto a launch rail. Dennis Smalling, the rocket lab's chief
engineer, began the countdown at 7:30 am. When he reached zero, Traveler IV shot
up off its launchpad, exhaust and flames pouring from its tail.
The USC
team is one of several groups of college students across the United States and
Europe that have been racing to send a rocket above the Kármán line, the
imaginary boundary that separates Earth's atmosphere and space. For most of the
history of spaceflight, sending a rocket to space required mobilizing resources
on a national scale. The V-2 rocket, which was the first to reach space in 1942,
took well over a decade to develop and cost the Nazis a fortune. In the eight
decades since, dozens of other countries-and a handful of billionaires-have
produced their own rockets capable of suborbital flight. But several student
teams, including some from the top aerospace universities in the US (Princeton,
MIT, UC Berkeley, Boston University), set out to show that they could do it
too.
As Traveler IV crossed the sky, the USC team and dozens of
spectators watched in apprehensive silence, shielding their eyes from the rising
desert sun. They scanned for signs of the rocket and listened to the avionics
lead, Conor Hayes, call out the altitude. Eight kilometers ... 13 kilometers ...
17 kilometers. Just under three minutes after launch, a member of the launch
team radioed in with the words that everyone was waiting to hear: "The drogues
have fired." The first set of parachutes had deployed at apogee, suggesting the
rocket had made it to space as planned. Peter Eusebio, the team's recovery lead,
let out a whoop and turned to embrace Sidney Wilcox, the team's launch
coordinator, and the pair began jumping with glee. All that was left to do was
find the rocket.
The USC rocketeers recovered their spacecraft 12 miles
downrange from where it had launched. For an object that had just been traveling
at five times the speed of sound, it was in pretty good shape. And when they
analyzed the flight data, they concluded with near certainty that the rocket had
breached the Kármán line, making the USC Rocket Lab only the second amateur
group to ever send a rocket to space. The vehicle had reached an altitude of
339,800 feet and achieved a top speed of 3,386 mph.
Although breaching
the Kármán line was the goal of the collegiate space race, this "official"
space boundary is somewhat arbitrary. NASA, for instance, gives astronaut wings
to any pilot that flies 50 miles above Earth's surface, which is some 60,000
feet below the Kármán line. By these metrics, the USC team was well into space
proper, even accounting for any measurement errors by the onboard accelerometer
tracking the rocket's ascent.
The USC Rocket Propulsion Lab has been
chasing this goal since it was founded in 2005. It began only a year after the
Civilian Space Exploration Team became the first group in history to send an
amateur rocket into space; that group repeated the feat in 2014.
Like the Civilian Space Exploration Team, the USC lab
focused on solid fuel rockets, which require far less complicated-and
dangerous-motors than the liquid fuel rockets launched by SpaceX or Blue Origin.
Some of the rockets being developed by the leaders of the collegiate space race
have two stages, but the USC team opted for a single-stage rocket. If you're
trying to get to orbit, which requires reaching speeds of more than 17,000 mph,
a two-stage rocket is a must, so as to jettison the dead weight of empty
propellant tanks. But for lower altitudes and speeds, a single-stage rocket can
do the trick.
THE WIRED GUIDE TO COMMERCIAL SPACE FLIGHT
In 2013, the
USC rocket team attempted its first space shot with the Traveler I, which
exploded just seconds after launch. A similar fate befell Traveler II, which was
launched the following year. Clearly, it was time to make some changes.
Following the failure of the first two Traveler rockets, the USC team began to
develop the Fathom rocket and Graveler motor as testbeds for flight systems that
would be used on subsequent space shots. The Fathom rocket was effectively a
scaled-down version of the Traveler rocket that allowed the USC team to build
multiple rockets in quick succession to see how the subsystems worked together.
After extensive ground tests, the team's Fathom II rocket set a record when it
reached an altitude of 144,000 feet in 2017. Other collegiate rocket teams had
reached only about 100,000 feet. The time seemed ripe to attempt another
spaceshot.
In September 2018, the USC team launched Traveler III, which
may have been the first collegiate rocket to make it to space. The team expected
it to reach about 370,000 feet, but the USC team failed to activate the avionics
payload, so none of its flight data got recorded. Prior to the launch of
Traveler IV, Tewksbury says, the team overhauled its operational procedures to
avoid a similar gaffe.
USC may have been the first collegiate team to make it
to space, but the race is far from over. A number of teams, including USC, are
exploring liquid-fueled rockets, despite the greater engineering challenge. They
offer several advantages, including greater degrees of control and the ability
to carry more payload mass to altitude. The huge costs of building such rockets
makes them daunting for universities, but the same thing could have been said
about solid-fueled rockets just 15 years ago.
Tewksbury says the USC team
is up for the challenge. But the team is also not done with its solid-fuel
rockets. The Rocket Propulsion Lab hopes to also claim the title of the highest
amateur rocket launch in history. This means adding another 50,000 feet to their
altitude, but once you've traveled 64 miles into the atmosphere, what's another
dozen miles?
Updated 05-22-2019, 11:00 pm ET: A previous version of this
article incorrectly identified the avionics lead as the range lead and stated
the rocket traveled 29 miles down range. The rocket actually traveled 12 miles
down range.
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