NASA prepares sensor breakthrough for upcoming hypersonic rocket flights

On March 26, Armstrong engineers conducted vibration tests using shaker equipment in the Environmental Laboratory, confirming the FOSS system's resilience under intense launch conditions. These successful trials follow earlier lab and flight evaluations in 2024, supporting FOSS's integration into Department of Defense research rockets.

FOSS uses a single hair-thin fiber to gather temperature and strain data along its length, significantly reducing the size and complexity of traditional sensor systems. This innovation allows more efficient data collection during extreme hypersonic conditions, which exceed Mach 5.

"There is no reliable technology with multiple sensors on a single fiber in the hypersonic environment," said Patrick Chan, FOSS project manager at Armstrong. "The FOSS system is a paradigm shift for hypersonic research, because it can measure temperature and strain."

Originally launched in 2020, the hypersonic version of FOSS evolved from earlier designs, including a space-rated system used in a 2022 NASA low Earth orbit mission. That unit, about the size of a toaster, has now been miniaturized to a compact device comparable to two sticks of butter.

Craig Stephens, associate project manager for NASA Armstrong's Hypersonic Technology Project, recognized early the need for streamlined sensors. "I challenged the FOSS team to develop a durable data collection system that had reduced size, weight, and power requirements," Stephens said. "If we obtain multiple readings from one FOSS fiber, that means we are reducing the number of wires in a vehicle, effectively saving weight and space."

In collaboration with the U.S. Air Force Test Pilot School and the 586th Flight Test Squadron, Armstrong led a six-flight series in 2024 to validate FOSS against conventional sensors. Mounted under a T-38 aircraft, the system gathered critical strain data during in-flight maneuvers.

"The successful T-38 flights increased the FOSS technology readiness," said Ben Tomlinson, lead for Armstrong's Technology Transfer Office. "However, a test at hypersonic speed will make FOSS more attractive for a United States business to commercialize."

Following the Air Force campaign, NASA sought further opportunities to validate the system. This resulted in the upcoming launch series, coordinated with the Department of Defense, to test FOSS in true hypersonic flight conditions.

"We have high confidence in the system, and we look forward to flying it in hypersonic flight and at altitude," Chan said.