Eric Gilligan, a native of Roxbury, N.J., is solving the equation of how to maneuver the Space Launch System (SLS) — NASA’s new heavy-lift launch vehicle — during flight.
Gilligan, 23, is part of team of young engineers at NASA’s Marshall Space Flight Center in Huntsville, Ala., who are developing innovative algorithms, or mathematical equations, for the flight control system on the SLS. That system is the “brain” of the vehicle, designed to steer it along the path to its destination in orbit. The team will test those algorithms on an F/A-18 jet, housed and operated at NASA’s Dryden Flight Research Center in Edwards, Calif.
“I’ve always had in interest in NASA,” Gilligan said. “Working on a fast-paced project like this that will actually fly and that will benefit SLS in the future is really cool. I’m really lucky to be a part of it and to work with some of the most talented engineers in the NASA community.”
As NASA develops a commercial supply line to and from the International Space Station, the agency also is embarking on SLS to ensure the ability to explore farther into the solar system. SLS will be America’ most powerful rocket that can carry the Orion spacecraft’s crew, equipment and experiments to places we’ve never been before in our solar system.
In addition to opening new frontiers for explorers who will travel on Orion, the SLS also offers many benefits for science missions to places such as asteroids, Mars, Saturn and Jupiter, including large payload fairings that reduce experiment design complexity and high performance that decrease travel time and, by extension, cost and risk.
The team has spent months working this first application of an adaptive augmenting control for the SLS flight system. It learns and responds to unexpected differences in the actual flight versus the preflight predictions. Enhancing algorithms already tested and used successfully on other NASA programs like the space shuttle, the new, adaptive flight system can learn and respond to anomalies in flight — like unpredictable winds — to increase safety and ensure the vehicle stays on its trajectory.
Gilligan and the team needed a way to test their concept before the actual first flight of SLS. That’s where an F/A-18 fighter jet at Dryden enters the story. Using an F/A-18 jet is an innovative and cost-effective way of getting actual flight test data early in the SLS program.
The flight system will think it is flying the SLS but will actually be running on the F/A-18. The F/A-18 test series, called the Launch Vehicle Adaptive Control (LVAC) experiment, began Nov. 14. Five flights are planned, with more than a dozen tests to be conducted during each flight. While the jet is in the air for 60-90 minutes, the experimental adaptive flight control system is tested in different scenarios for up to 70 seconds at a time.
“We have 20 test cases, each simulating some off-nominal conditions, like higher thrust than anticipated or the presence of wind gusts, to see if the algorithm responds as we designed it to do,” Gilligan said. “The tests might reveal something we hadn’t thought about in our algorithm, which we can go back and modify as necessary.”
Gilligan will be manning the control room for all the tests with the team. He’ll be looking at the data coming in real time, making decisions about the test scenarios that will be relayed to the pilot on flight days.
After the initial flight tests, the team will return to Marshall, go over the data and make any changes to the test plans for the remaining flights.
Gilligan earned a bachelor’s degree in aerospace engineering from Pennsylvania State University in State College. He joined NASA soon after graduating in 2012.
The first flight test of the SLS is scheduled for 2017, which will feature a configuration for a 70-metric-ton (77-ton) lift capacity and carry an uncrewed Orion spacecraft beyond low-Earth orbit to test the performance of the integrated system. As the SLS evolves, it will provide an unprecedented lift capability of 130 metric tons (143 tons) to enable missions even farther into our solar system to places like Mars.
For more information about algorithm development and F/A-18 testing, visit:
https://www.nasa.gov/exploration/systems/sls/research-jet-tests-sls.html
https://www.nasa.gov/exploration/systems/sls/i-am-building-sls-gilligan.html
For more information about SLS, visit:
https://www.nasa.gov/exploration/systems/sls
Kimberly Henry
Marshall Space Flight Center, Huntsville, Ala.
256-544-0034
kimberly.m.henry@nasa.gov