Jason Reed / Reuters

Aeromexico Flight 773 from Guadalajara was just about to land last week when crew members heard a “pretty loud bang,” according to a cabin recording. A mysterious aerial collision had left the nose of the passenger jet badly mangled. By the time it landed safely in Tijuana, there was no confirmed culprit but one likely suspect: a drone.

If confirmed, the incident would represent one of a very small but growing number of mid-air crashes involving the small flying robots.

The potential for tragic accidents—or deliberate attacks—has grown as drones have proliferated among hobbyists and businesses. Just on Thursday, flights at one of London’s biggest airports were suspended after two drones were spotted over its airfield, disrupting flights for tens of thousands of passengers. In the United States, the industry is expanding faster than regulation can contain it. That has left a vacuum, and a burgeoning field of private actors is scrambling to fill it. Though technology does exist to track, divert, or disable rogue drones, those systems are being tested and rolled out slowly, on an ad hoc basis in a handful of locations around the country. There’s still no coherent nationwide system for countering the risk posed by rogue drones, whether their operators are “clueless, careless, or criminal,” as one official put it.  Will it take a real catastrophe to put such a system in place?  

The first reported drone crash involving a civilian airplane took place last year, when one of the machines struck the wing of a small charter aircraft in Canada; though that plane, too, landed safely, Canada’s transport minister warned that, had the drone damaged the engine or the cockpit, the result could have been “catastrophic.” The threat isn’t limited to aviation. Small drones have been implicated in a reported assassination attempt on President Nicolas Maduro in Venezuela; used in attacks on or surveillance of U.S. troops and their allies in Iraq and Syria; and flown into a stadium to harass soccer players in Serbia.  

Events like these are what worry people like Jaz Banga, the CEO of Airspace Systems, a Silicon Valley–based company that works on drone safety. In a recent interview, he told me that both the San Francisco Police Department and Major League Baseball have deployed his company’s new detection system to scan the skies for drones during two high-profile events: San Francisco’s Fleet Week this fall—which involves a massive display of Navy ships and airplanes—and the 2018 World Series games in Boston and Los Angeles. The system, called Galaxy, functions as a kind of 3-D map of the air, and it offers the option to deploy a drone-capturing drone in case of a threat.

Large, spectator-packed events are hard enough to secure in two dimensions, but you can’t put checkpoints and metal detectors in the sky. (For instance: In the assassination attempt on President Maduro in Venezuela in August, two drones rigged with explosives sailed close to him before blowing up; one unarmed drone landed harmlessly at the feet of German Chancellor Angela Merkel at an event in 2013; and one, carrying a small amount of radioactive sand, landed on the roof of the Japanese prime minister’s office in 2015.)

Fleet Week in particular centers on a massive air show, featuring, among other things, Navy fighter jets flying in formation over San Francisco’s Golden Gate Bridge. There are, Banga said, “a million people plus in the city that just come out to hang out and watch loud airplanes fly, [and] the brass from the U.S. military is hanging out here, too.”

The drones that people worry about in this context are not the ones developed by the U.S. military for surveillance and air strikes. They’re smaller, cheaper, commercially available gadgets like quadcopters that can have many recreational or business uses, from getting cool aerial footage to delivering emergency supplies to monitoring crops or even traffic violations.

With an event like Fleet Week, the risk of a mid-air collision could materialize from someone who wanted to get a closer look at the air show via a drone-mounted camera, or a hobbyist who wanted to see how high his or her machine could fly. One of those devices might collide with a plane, or crash and injure someone in a crowd. That’s assuming the operators don’t have nefarious ends, which an observer from the ground wouldn’t necessarily be able to determine.

As the risk of accident or malfeasance has grown, so has the industry devoted to countering rogue drones. “It’s almost the Wild West of counter-drone [development] out there right now,” said Banga. Various companies offer different kinds of monitoring systems: net guns that can be used to capture drones and bring them down, vehicles like Airspace’s that can tow a potentially dangerous flying object away from a crowd and to safety, and even “geo-fencing” software that physically repels a drone from flying into certain airspace.

So far, however, none of these systems are deployed in any comprehensive way around the United States. Instead, a patchwork of systems is being used in a handful of sensitive areas,  such as airports and stadiums. “Most cities don’t have anything,” says Tim Bean, the CEO of Fortem Technologies, another drone-security company, which launched its own detection services in recent months. The technology is currently being tested at Salt Lake City International Airport, and one other that Bean declined to identify. Most of the remaining hundreds of airports around the country aren’t using any dedicated drone-detection services, and drones are too small for most standard radar to detect.

A further complication: The technology has moved much faster than the regulations that will ultimately govern it. The Federal Aviation Administration has rules generally requiring drone users to register their devices, display what amounts to a license plate, observe height and weight limits, and stay away from places like airports and government buildings. But some users break the rules, whether by accident or intentionally. The fact that you can’t fly a drone in Washington, D.C., didn’t stop a man from crashing one on the White House lawn in 2015, for example. The requirement to stay away from other aircraft didn’t prevent a drone’s collision with an Army helicopter near Staten Island in 2017.

It’s a bit like how motorists speed or run stop signs. Except that roads are finite pathways, and there’s a well-developed nationwide system of traffic rules and licensing requirements for motor safety.

Where drones are concerned, regulators are dealing with what amounts to virtually infinite road space in three dimensions and trying to figure out where to put the stop signs. Another problem is how to pull over miscreants whose license plates you can’t necessarily see and whose operators aren’t necessarily anywhere near the vehicle.

The enforcement parameters are still being hammered out slowly. Until recently, it would have been illegal to shoot a potentially threatening drone out of the sky or to jam its radio frequency, but new legislation that was passed this fall grants this authority to federal law enforcement. (It’s still unclear what the legislation means for local cops and private actors.)

Michael Thompson of the San Francisco Fire Department, who has coordinated emergency-incident response for Fleet Week for the past four years, told me that this was the first time he’d used a drone-detection system—though in his main duties as a department battalion chief, he’s encountered plenty of drones, and never gladly. “We hate them,” he said. Sometimes they’re just a nuisance hovering over major fires to get footage; other times they have actually impeded fire mitigation, because planes dropping fire retardant need to avoid their path.

There were no drone-related emergencies during Fleet Week, though the system did detect a handful of incidents. In one of them, it spotted a drone that hadn’t even taken off—the vehicle was powered on and sitting in a boat in the San Francisco Bay. The police dispatched their own boat to warn the operator not to use the device given the flights taking place overhead. “We’re worried enough about pelicans,” Thompson said, “let alone idiots with drones.”

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