Originally deployed to record re-entry signals of the OSIRIS-REx return capsule, a T-shaped fiber optic cable draped across the ground at a Nevada airfield also captured unique aspects of a Cessna 172’s speed and maneuvering.
Researchers at the 2026 SSA Annual Meeting said the findings help demonstrate the potential for rapid deployment of fiber optic cable and Distributed Acoustic Sensing (DAS) in environments where burying the cable isn’t feasible.
The study by Elisa McGhee, a Ph.D. candidate at Colorado State University and former Air Force pilot, and colleagues also adds to the growing body of research on aircraft detection and flight analysis using DAS.
DAS uses the tiny internal flaws in a long optical fiber as thousands of seismic sensors. An interrogator at one end of the fiber sends laser pulses down the cable that are reflected off the fiber flaws and bounced back to the instrument. When the fiber is disturbed by acoustic or seismic waves, it changes length. This length change is converted to strain units by researchers for analysis.
Acoustic waves generated by flying aircraft vibrate the air and the ground below, transforming sound energy into motion that can be detected by both DAS and traditional seismic sensors.
McGhee and her colleagues deployed fiber optic cable at the Eureka Airfield and in Newark Valley, Nevada, prior to the 24 September 2023 return of NASA’s OSIRIS-REx Sample Return Capsule, the fifth re-entry from interplanetary space since the end of the Apollo era. The cables were one of many geophysical instruments aimed at this “artificial meteor .”
On 22 September 2023, the researchers opportunistically took videos of two aircraft operating at the Eureka Airfield. One was a two-blade propeller Cessna 172 based out of the airfield and flown by a local pilot and his cousin.
“My teammate [Loïc Viens] introduced himself to them because we were positioned on the aircraft ramp with our DAS Interrogator Unit near the hangar and fuel pit,” McGhee recalled. “The pilot said he’d takeoff and fly a few practice approaches for pilot proficiency, and then depart to northern Nevada.”
McGhee and her colleagues paired data from seismic stations, a section of shallow-buried fiber (7 cm) and the surface-draped fiber with observations from their Cessna 172 video to demonstrate how aircraft speed and maneuvering were captured in the DAS and seismic data.
“Having fiber and seismometers positioned on the airfield is a unique and perfect location to study aircraft,” said McGhee. “I haven't seen studies where these instruments are directly on an airfield in this way.”
The researchers used data from the surface-draped fiber and the shallow buried fiber running parallel to the taxiway to estimate taxi speed. Using the buried fiber, they could follow the plane’s traffic pattern of a rectangular circuit through the sky.
Using the seismometer data to create seismic spectrograms, McGhee and colleagues also observed changes in the plane’s propeller RPM (revolutions per minute).
Other recent studies have focused on the constant RPM of overflight, but the data collected on the Cessna 172 offer a more dynamic, real-world look at aircraft maneuvering. “When the aircraft turns, changes speed, or alters the power setting (RPM), the frequency spectra are also dynamic,” McGhee said.
The researchers will continue studying the deployment data to learn more about how to improve observations from surface-draped fiber. Also at the SSA meeting, McGhee’s study co-author Carly Donahue of Los Alamos National Laboratory discussed the potential of surface-draped DAS on the Moon .