When Christi Johnson finishes clocking an eighth of a mile in 4.7 seconds, she jumps out of the dagger-shaped drag racer while its wheels are still smoking, pulls off her helmet… and the next morning, pulls on her lab coat.
As a technical professional at the Department of Energy's Oak Ridge National Laboratory, Johnson has developed, built and tested hardware and software for innovations including a jet blast deflector, an ultrasonic dryer, a sensor system for driver recognition and waveguide inspection tubes for the world's largest magnetic fusion device. But Johnson, who works in the Multimodal Sensor Analytics Group, said her scientific career really began when she was a little girl eager for her turn in a fast car.
A native of Maryville, Tennessee, Johnson grew up at the speedways across the South where her father raced. "Being around race cars and tools is mostly what got me into engineering. Those are my earliest memories as a little kid," said Johnson. "I've always understood things by taking them apart with my hands and putting them back together." In the garage, she repaired her Barbie jeep while her dad perfected the dragster.
By age 10, she took the driver's seat in her own junior racer. (Picture a go-kart that zooms 70 miles per hour.) She has been racing in non-professional races ever since.
Her father, who has won a world championship, buys the car's chassis and body but builds and wires the rest himself. The two Johnsons function as each other's pit crew, taking turns behind the wheel during the same events most weekends from April to November for a prize purse that might just cover the next round of car upgrades.
Johnson's father became a professional welder after teaching himself by building race cars after work. "When I was young, Dad instilled that racing was a privilege," Johnson said. "It's expensive, so it has to be earned: If you make good grades and do your best, then you get to go to the racetrack."
Johnson stayed in the fast lane through high school, weaving between academic and trade tracks on weekdays and racetracks on the weekend. "I figured out the formula for drag racing in my physics class," she said.
She's not kidding: She competes in a concise type of drag racing, called bracket racing. The winner is not the driver of the fastest car, but the driver who most accurately estimates exactly how long it will take to cross the finish line. The goal is to get as close as possible to that calculation - but no faster - through perfect reaction time and control.
"A race between two people is a big math problem that comes down to whoever's time diverges the least from perfect," Johnson said. In other words: applied physics, at 145 miles per hour.
But Johnson was learning other lessons from high school unrelated to academics or cars. She ranked welding, automotive and carpentry as her top trade course interests. To Johnson's surprise, her guidance counselor placed her in cosmetology, saying that as a girl she'd probably be happiest there.
Johnson made the best of it. In fact, she excelled at nail care, even progressing to the Skills USA national championship competition. However, cosmetology was just a pit stop. College had always been her chosen destination. And as a first-generation college student, Johnson became one of only three female physics majors in her class at the University of Tennessee.
"I'm very comfortable in male-dominated fields, because that's basically all I've ever known," Johnson said. "At the track, you kind of got discounted as a female. There was this mentality that because you were a girl, you weren't as good. That just made me want to beat them even more. Coming through school in engineering, I definitely had that same sense of having to prove why I was there."
She learned to power through adversity, whether skepticism from professors or a high-speed wreck at the racetrack. Her focus paid off. One of her professors recommended Johnson for an ORAU Science Undergraduate Laboratory Internship. Roger Kisner, a senior researcher in a sensors and controls group, mentored her after she graduated with a bachelor's degree in physics. He hired Johnson as a staff technical professional in 2016.
For her first ORNL project as an intern, Johnson helped develop a specialized lighting system for airport runways. FedEx had outfitted cargo planes with thermal imaging, allowing for delivery flights in tough weather conditions. But the company's cameras relied on a heat signature missing from new LED runway lights. "We came up with some custom circuitry to run an infrared ampule the FedEx system could recognize," said Johnson, who shared in the resulting patents and technology commercialization awards.
Johnson has applied her instrumentation design, mechanical design, software development and fabrication skills to field testing electrical systems, sensors and hardware assemblies. She was part of a team that won an R&D 100 Award in 2021 for a technology that combined mapping, software and hardware for targeted distribution of salt brine on local roads, protecting drivers during icy conditions while saving taxpayer dollars.
Johnson and her colleagues earned another technology commercialization award for an optical array that reconstructs clearer pictures of faces photographed through a windshield of a moving vehicle. That helped lay the groundwork for a four-year intelligence project called Biometric Recognition and Identification at Altitude and Range, or BRIAR, which developed systems for facial, whole-body and gait recognition from a distance and at odd angles. Johnson led design and fabrication of BRIAR sensor hardware.
To hone the technology, volunteers were needed so researchers could build datasets of images for training the recognition algorithm. During more than half the project, Johnson led the range team preparing the hardware and sensors for image collecting events across the U.S. Each event required more than six weeks of setup. At the largest event, the team installed 76 sensors over 14 range stations covering 1,000 square meters of tarmac. "I think we should all get Olympic medals for rolling ethernet cables and power cords," Johnson added, no stranger to hours on the tarmac.
She also leads by example. "Christi Johnson is the kind of teammate every technical team hopes for: brilliant, humble and fiercely reliable," said David Cornett, who led the BRIAR project for ORNL. "Christi earned the trust and admiration of her peers by consistently demonstrating her deep technical expertise, proactive leadership, and a willingness to step up wherever needed. This combination of excellence and integrity makes Christi an ideal technical team lead and a powerful role model for women pursuing careers in STEM."
But she doesn't rest on those accomplishments in the field. Johnson continues to step up her skills, now managing a lab where she was once an intern. She shares those skills and enthusiasm by mentoring new lab space managers, valuing the many perspectives each individual contributes. After all, her own curiosity, creativity and drive make Johnson more than the sum of her parts.
UT-Battelle manages ORNL for the Department of Energy's Office of Science, the single largest supporter of basic research in the physical sciences in the United States. The Office of Science is working to address some of the most pressing challenges of our time. For more information, please visit energy.gov/science . - Heather Duncan
