A wayward drone almost hit a senator’s plane. Now she’s a drone safety hawk.

The most revealing moment in Elaine Chao’s otherwise dry confirmation hearing to become secretary of transportation came when Tammy Duckworth, Illinois’s freshly elected senator and a licensed pilot, described the time a drone almost got her killed.

“I have flown not too far from here and was flying at 2,500 feet when a remotely controlled vehicle flew off the nose of my aircraft and missed my propeller by about 2 feet,” Duckworth said. “Let me just say it scared the living heck out of me. It should not have been there. And so I will be monitoring the drone rules and programs very closely.”

It was a vivid reminder of the very high stakes in drone regulation. Lots of people at Wednesday’s hearing agreed that the Federal Aviation Administration needs to protect safety without unduly stifling innovation, but Duckworth’s anecdote helped to make the abstract concept of safety very concrete.

If she’s confirmed as Donald Trump’s secretary of transportation, Chao and her team at the FAA will have some big decisions to make about the future of unmanned aviation. Amazon and other companies have been working on technology for automated drone deliveries. But these services can’t operate in the United States because current regulations require drones to operate within view of a human operator.

There’s a strong case for the FAA to revise these rules. But it’s never going to be realistic for the agency to totally deregulate this market — the danger of poorly managed drones running into passenger airplanes or crashing in populated areas is too great.

One big question for the FAA will be how to ensure that people operating drones actually comply with the rules. As Duckworth notes, the drone that almost hit her airplane should never have been 2,500 feet in the air — an altitude that’s reserved for larger aircraft. But right now, compliance with the rules for small drones is largely on the honor system.

One direction the FAA could go is to require all drones to participate in a uniform tracking scheme so the authorities can quickly identify vehicles that fail to follow the rules. That could be as simple as requiring drones to display serial numbers, or as complex as requiring them to have transponders or GPS tracking devices that allow the authorities to track their progress at all times.

In a pair of white papers published in 2015, Amazon laid out its own vision for drone delivery regulations. Autonomous drones would need a GPS and highly accurate geospatial data, a reliable internet connection, the ability to communicate wirelessly with other drones, and sensors to detect and avoid collisions with other objects in the sky.

Presumably, that would serve Amazon’s business needs. But there’s a risk that these relatively complex requirements could prove too burdensome for smaller companies or — conversely — that it leaves too much room for less reputable companies to build drones that endanger people’s lives and safety.

Ultimately, though, there’s no way to completely eliminate risk while allowing experimentation. If more unmanned devices start whizzing through the air, one of them will eventually collide with an airplane or crash on a human being. Maybe even a senator.

Correction: I originally described Duckworth as an “amateur pilot,” but in light of her military service it’s more accurate to describe her as a licensed pilot.