LOS ANGELES – It was an otherwise routine flight until, at an altitude of about 1,100 feet east of this city's downtown, the crew aboard the news chopper heard a loud bang.

"The pilot and I just looked at each other. 'What was that?'" reporter Chris Cristi of KABC-TV remembers thinking.

Not far from their base, they landed Air 7 HD, as their Eurocopter is known to viewers, and discovered a dent in the horizontal stabilizer and next to it, a gash and one-inch hole. There was no blood or feathers as if they had hit a bird. The most likely cause was a drone.

The National Transportation Safety Board says it's awaiting results from a lab before it can confirm a drone was involved. But it wouldn't be the first time that a drone and aircraft mixed it up. In 2017, an Army Black Hawk copter collided with a drone that wandered into its flight path near Staten Island, New York.

In both cases, the outcome could have been catastrophic. Drones are relatively small, difficult for pilots to spot and often flown recreationally by novices. If one crashed through a windshield or into an engine intake, they could down a helicopter or jetliner.

As Cristi puts it, the collision between the copter and drone "wasn't scary per se, but it was scarier when we saw the damage."

Alarmed at their rising numbers – 1.6 million drones and 167,841 registered operators in the U.S. – the Federal Aviation Administration is trying to institute tougher rules that would allow authorities to identify drones and their operators more quickly. The plan, however, has gotten flak from hobbyists and some professional drone operators. They say the feds' plan is too far-reaching and that many of the existing model aircraft and drones can't meet the requirements.

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Few would deny drones have complicated the airspace. The FAA, which keeps a log of drone sightings by private and commercial pilots, air traffic controllers and the public, reported more than 2,000 encounters last year. Some came uncomfortably close.

Incidents reported over a single five-day period last June included:

• Pilots of an Airbus A319 sighted a drone passing directly underneath their Airbus A319 as it was on final approach in New Orleans.

• A drone passed 200 feet below a Boeing 737 while flying at 6,700 feet near Minneapolis.

• A single-engine Piper found damage to the left wing that its pilot believes could have come from a drone impact.

Drones are hard to detect. Pilots could only spot hovering drones 13.6% of the time on airport approaches in tests conducted by Oklahoma State University and Embry-Riddle Aeronautical Institute. When the drone was moving, the detection rate improved to only 50%.

"These things are very hard to see even when you know where to look," said Assistant Professor Matt Vance, one of the Oklahoma State researchers.

Though collisions with planes are rare, they have the potential to cause serious damage, perhaps even a crash.

An airplane wing tore open in a test that simulated a small drone crashing into it at 238 miles per hour, the University of Dayton Research Institute found.

Authorities haven't hesitated to shut down airports or other airspaces if a drone is detected. Gatwick, the London-area international airport, was closed for more than a day in 2018 when drones were detected in the vicinity. Last year, a drone sighting interrupted operations at Newark Liberty International Airport in New Jersey.

Such incidents have spawned the advent of systems that can detect drones, like one used at Dallas/Fort Worth International. It allowed for the discovery of drones on two occasions deemed too close to runways over 18 months, said Paul Sichko, vice president of operations.

When it comes to errant drones, their operators fall into one of three categories: "the careless, the clueless and the criminal," said Chad Makovsky, executive vice president of operations at the Dallas/Fort Worth airport.

It's that last category – criminal – that causes some of the biggest worries nationally. Even small recreational drones sold online can be rigged to carry crude bombs.

Two drones carrying plastic explosives were launched in what was believed to have been an unsuccessful assassination attempt against Venezuelan President Nicolas Maduro and other officials two years ago.

And in Allentown, Pennsylvania, a man was indicted in September for allegedly having an unregistered drone and seven homemade bombs in a case related to the stalking of his former domestic partner, the U.S. Attorney's Office said. The defendant, Jason Muzzicato, 43, also had 10 guns in his possession.

“It does not take much imagination to conjure up the enormous harm that can result from the combination of illegal firearms, explosives, and drone aircraft,” said U.S. Attorney William McSwain said in a statement.

One big step in trying to protect against drones is being able to identify them, the FAA contends. Underscoring the need: the mysterious clusters of drones that appeared in the skies of Colorado and Nebraska. The Colorado Department of Public Safety has since reported it found no evidence of illegal activity and in some cases, observers were mistaking bright stars for drones.

Expect more drone sightings as their numbers continue to increase.

While Amazon and others have grabbed the headlines for the notion of using drones for small-package deliveries in remote areas, a variety of companies are other practical applications that replace more expensive, manned aircraft. Drones can replace aircraft for inspections of railroad tracks, power lines and above-ground pipelines. Farmers are using them to survey fields.

Barclays estimates the commercial drone market will increase from $4 billion in 2018 to $40 billion by 2024.

The biggest problem, however, involves recreational amateurs who may learn to fly drones without registering themselves or learning the rules.

"A lot of people are not licensed and don't understand the responsibility of drone pilots," said retired USAirways pilot John Cox, who himself saw a drone once while flying.

The Federal Aviation Administration has proposed new rules that would require the small, unmanned craft and their operator to be easily and quickly identified. The Remote ID proposal would apply to operators of drones weighing around half a pound or more. They would need to broadcast their position, transmit the data via the internet or only be flown in a designated, FAA-approved flying area.

“Remote ID technologies will enhance safety and security by allowing the FAA, law enforcement, and federal security agencies to identify drones flying in their jurisdiction,” said Transportation Secretary Elaine Chao in a statement.

The proposal strikes those who use drones for nature photography or other pursuits in wide-open rural, desert or mountain areas as unnecessary. They worry about not being able to find an internet connection in certain areas or the expense of complying with the requirements. Among those voicing concerns are those who fly drones as part of their jobs.

"Here's big brother stepping in and taking over the skies," said Mark Hamilton, a commercial drone pilot with DronesiViews, an aerial photography business in Phoenix.

The rule could require retrofitting of drones to try to comply, he said. It might make some drones obsolete.

Model-aircraft owners, who appear to have left the bulk of the more than 53,112 comments online on FAA's website regarding the new rules, say the plan would hamper their hobby. Small model planes would meet the definition of a drone under the proposal.

Many model planes are flown in places that don't have an internet connection or, because of their lightweight construction, may not be capable of being fitted with a transmitter, said Tyler Dobbs, director of government affairs for the Academy of Model Aeronautics.

Opponents say the rules, at worst, could ground many of today's drones, requiring operators to buy new ones. For many, they warn, it could kill the hobby.

But the FAA said it had to act.

“As a pilot, my eye is always on safety first,” said FAA Administrator Steve Dickson in a statement when the new rule proposal was introduced. “Safety is a joint responsibility between government, pilots, the drone community, the general public and many others.”

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