USC Students Set Altitude and Speed Records in Amateur Rocketry
On 20 October 2024, in Nevada’s Black Rock Desert, the University of Southern California’s Rocket Propulsion Lab (USCRPL) achieved a milestone in amateur rocketry. Their student-built Aftershock II rocket reached an altitude of 470,400 feet—143.3 kilometers—surpassing the previous amateur record of 385,800 feet set in 2004 by the Civilian Space eXploration Team’s GoFast rocket. The vehicle also set a new speed record for an amateur launch, hitting 5,283 feet per second, or 1,610 meters per second, exceeding the prior mark of 5,019 feet per second.
The 13-foot-tall, 330-pound rocket was the product of meticulous engineering and cross-disciplinary collaboration. Around 100 students from the USC Viterbi School of Engineering contributed, spanning mechanical, aerospace, chemical, electrical, and computer engineering, as well as computer science. Dean Yannis Yortsos emphasized this breadth: “This is not simply aerospace engineering students. We have mechanical engineering. We have students who understand propulsion and also fuels. We have electronics engineers. We have computer scientists, chemical engineers.”
Operations Lead and aerospace engineering major Jayna Rybner described the experience as transformative. “It’s probably the most incredible thing I’ve ever gotten an opportunity to be a part of,” she said. “Seeing the hard work that we put in every day be able to come together and to see it actually really succeed, and to see it go to space was the coolest thing ever, knowing that just a bunch of college students did that.”
Technological innovation underpinned the mission’s success. Aftershock II featured a custom thermal protection system with titanium-coated fins and a new heat-resistant paint to endure the extreme aerodynamic heating at hypersonic velocities. The team also designed and fabricated their own avionics, including computer systems and circuit boards, enabling real-time tracking and live telemetry throughout the flight. This capability proved critical for both flight analysis and recovery operations. The post-flight Apogee Analysis confirmed the altitude with an uncertainty margin of ±27,300 feet, using data from multiple onboard sensors.
Professor Paul David Ronney, chair of USC’s Department of Aerospace and Mechanical Engineering, praised the rigor of the team’s approach. “They went to great lengths to ensure that they had checked everything, and used multiple sources of multiple sensors to determine what the altitude was, and gave the limits of uncertainty of their altitude,” he said. He also noted the organizational dimension: “It’s like a mini-corporation. The students that have come out of that lab… have gone on to leadership positions in all of the major aerospace companies.”
Founded in 2005, USCRPL has pursued a clear mission: to design, build, and launch student rockets into space. Over two decades, the lab has executed eight missions using more than a dozen unique airframes and propulsion systems. In 2019, its Traveler IV rocket became the first student-built vehicle to cross the Kármán line at 328,083 feet. Aftershock II now extends that legacy with both altitude and speed records.
Yortsos underscored the lab’s self-reliance: “It is important to know that all this technology is developed by our students themselves. It’s all done in-house. Our students get advice from the faculty, but they develop everything on their own… We’re so proud of them because they can do this on their own. They learn how to transfer this knowledge from one year to another.”
Executive Engineer Ryan Kraemer noted that the team is approaching the regulatory ceiling for amateur rocketry—about 490,000 feet—beyond which special clearances are required. “Unless we want to get special clearances, we are going to have to stay under that height, but we are going to move forward in the sense of flying research payloads. We’re excited to use, essentially what is a sounding rocket at this point, to gather data for whoever wants it.”
For Rybner, the record flight is a foundation for future cohorts. “Some newer members of the club walked over, and we said to them, ‘Hey, this may have been the coolest thing we’ve ever done, but this is not going to be the coolest thing you guys have ever done.’ This freshman class [has] four more years to take what we did and do it even crazier, even better, even cheaper, even better to manufacture.”
