This post is also available in: heעברית (Hebrew)

Researchers are developing methods to evaluate the risk posed by small unmanned aircraft to anyone on the ground. The research is key to enabling flights over people, as Federal Aviation Administration (FAA) regulations for unmanned aircraft systems (UAS) currently prohibit these flights unless a special waiver is granted.

The research team is from Virginia Tech — home to both a Federal Aviation Administration-designated test site for unmanned aircraft systems and a world-renowned injury biomechanics group.

Current regulations are designed to prevent injuries if an aircraft descends unexpectedly or the pilot loses control. But they present challenges for efficiently conducting operations that otherwise seem ideally suited for unmanned aircraft, such as package delivery and aerial journalism, according to the Virginia Tech website. Most applications face steep hurdles in densely populated areas, where it would be virtually impossible to ensure that there was no one beneath an aircraft’s flight path.

“The majority of applications would be much more effective if they weren’t restricted from operating over people, but you have to demonstrate that it can be done safely,” said Mark Blanks, the director of the Virginia Tech Mid-Atlantic Aviation Partnership, which runs Virginia Tech’s test site. “The risk of injury is very low, particularly with small aircraft,” Blanks said. “This research can mitigate those risks further.”

The FAA is working to develop regulations that could allow certain small unmanned aircraft to fly over people depending on their injury risk.

Experimental methods will be tested in order to systematically assess the potential of unmanned aircraft to cause injuries of varying degrees.  “What we can do at the test site is help provide the data that can inform that decision-making,” said Blanks, who also chairs an industry standards subcommittee developing guidance for safe flights over people.

“I see this research as having two key pieces,” Blanks said. “First, what is the risk of injury: how likely are these impacts, how hard are they, and are impacts at that level dangerous? And second, what can we do, from an engineering or operational perspective, to reduce that risk?”

The team has already begun the first phase of the project. Different unmanned aircraft are flown directly into a test dummy, mimicking what might happen if an aircraft accidentally hits someone. Sensors in the dummy’s head and neck measure the force generated by the impact. Other parts of the project will involve simulating impacts in the lab and conducting drop tests, which can measure the force exerted by a falling aircraft. This comprehensive experimental protocol will allow the team to study injury risk in a variety of possible impact scenarios.

The test methods can also be used to evaluate the effectiveness of safety features that unmanned aircraft manufacturers may design to help their aircraft meet any federal standards that are developed.

The Virginia Tech Mid-Atlantic Aviation Partnership has tackled key challenges in the integration of UAS into the national airspace — for example, traffic management for unmanned aircraft, detect-and-avoid technology, and flights beyond the visual line of sight. This fall, a groundbreaking research collaboration with Project Wing investigated package delivery, with food as the cargo.