The Rocketeers
collegiate team to launch a liquid-propelled rocket into space.
Here’s why they say finding flaws in their design is critical.
Growing up, Jason Deng remembers watching countless TV shows and movies about space with his dad. The 1995 docudrama “Apollo 13”, about NASA’s failed third lunar landing mission, was one in particular that stuck with him, said Deng, now an undergraduate in college—so much so that he became inspired to pursue studies in aerospace engineering at the University of Texas at Austin. And these days, he’s not only studying rocketry, but competing in a brand-new space race.
Last fall, Deng joined the university’s Texas Rocket Engineering Lab, or TREL, founded in 2018 to compete in the Base 11 Space Challenge. The international contest will award a $1 million prize to the first student-led university team that successfully designs, builds and launches a liquid-propelled, single-stage rocket to an altitude of 100 kilometers, which constitutes the Karman Line, the boundary of Earth’s atmosphere.
“I think humans have always had an obsession with the unknown. We're natural explorers, and people have looked up to the cosmos, trying to explore it for thousands of years,” explained Deng. As part of TREL, now he has an opportunity to help build a rocket that can fly to the edge of space.
The TREL organization currently has about 275 active student members who have spent the last three years working in small teams to design and manufacture different components of the 28-foot rocket, named Halcyon. Within this organization, Deng’s role is vital. As a director of test operations for TREL, Deng helps to manage the process of evaluating the efficacy of each piece of the rocket before the actual build. Deng and his colleagues spend months probing for flaws in each component, trying to determine what might go wrong in a real-world situation. The data that is gathered from these tests are then used to adjust the designs as needed in order to minimize any risk prior to the actual launch. In essence, each failed test gets the group closer to the creation of a workable rocket.
“A lot of our teams are working to figure out at what point things break,” Deng notes. “It’s how we determine how things will work in the real world and how our designs can be optimized and changed in order to meet the standards that we need.”
Building an engine
through error
Of course, one of the most important aspects of a rocket is the engine, without which the machine can’t fly. The initial testing of a rocket engine is known as a “hot fire test.” In May, TREL successfully completed its first-ever hot fire test. It was the first in a series of planned assessments that will be completed on Halcyon’s engine prototype this summer. The data obtained from these tests—metrics on thrust, efficiency, temperature—will be key to optimizing the actual flight engine, which will be 3D-printed from copper.
Ben Juenger is an engine test lead for TREL. Like Deng, he’s also an aerospace engineering undergrad who joined the lab last fall. During a hot fire test, Juenger and his team mount the test engine on a structure called a test stand that contains various valves and sensors; this set-up enables the students to control the flow of the propellants—liquid oxygen and an ultra-refined kerosene—and evaluate the performance of the various engine components.
Although the first hot fire test was considered a success, Juenger said, they still found a handful of issues that they would never have discovered had they not evaluated the engine in the first place. For example, one of the valves that is designed to push out—or “purge”—the propellants didn't work as effectively as it should, creating some instability.
“It was not something that was super catastrophic, but had it been on our next engine, which is probably going to be a less forgiving system, that may have been a risk. It’s definitely very critical that we’re making these mistakes now and not later,” noted Juenger.
Having hardware and software that has allowed the TREL team to collect this kind of comprehensive information has been critical to their testing efforts. The group has been utilizing tools provided by NI, a company that supports engineering performance and innovation through test and measurement solutions. The testing tech has helped the students capture performance results from sensors and convert those results into data that can be seamlessly analyzed. From there, Juenger says, the group is able to make the necessary adjustments to the rocket components.
“You can never design something and manufacture it and just expect it to work,” he said. “It has to be very thoroughly tested and qualified, especially when it's going on something like a 28-foot rocket intended to reach space—and especially when there are real risks, like with dangerous propellants and systems like that. We then take all the lessons we learn with our test stand on the ground and transfer that into the rocket.”
Prepare for launch
Once the initial testing is complete, all of the systems will be integrated into the rocket for what’s called a stage test, said Deng, during which the team will ignite the rocket while it’s still on the ground to verify that everything functions as it should as one complete unit.
System integration will be a challenge in and of itself, Deng said. “We have our systems integration team that tries to make sure that all the different teams are building the same rocket and that everything’s able to fit together, but things behave differently in the real world. A big issue that we're trying to figure out is if components don’t mix together well.”
To assist TREL on that front, NI also provided a testing solution that allows students to generate an identical digital version, or digital twin, of each rocket component. The tool allows the students to conduct computer-based simulations of how the components will fit together, giving them a window into the efficacy of the integration before the physical rocket is put together and ignited.
While it remains unclear when exactly the launch will take place, it’s these types of tests that give TREL students confidence that they’ll eventually achieve the goal of sending Halcyon to the Karman Line.
“The test phase is so critical. We will always learn something from these tests, and we’ll always have failures, hopefully non-catastrophic,” said Juenger. “But the point of doing the test is so that when we finally get to the rocket, we’re never at risk of having those kinds of problems.”
