A new era in aviation began Monday, when the Federal Aviation Administration cleared the way for businesses to launch small drones in the national airspace.

It’s a development that could untether the economic potential of drones and the technology’s promise to change how we live. Drones already have shown promise for use in real estate, agriculture, construction and utility inspections, news gathering and search-and-rescue operations.

Beyond simply clearing the way for businesses to fly small drones — defined by the FAA as weighing less than 55 pounds — the new commercial drone rules clear away the ambiguity about the FAA’s authority to regulate them. Drones have skyrocketed in popularity in recent years, but the agency’s efforts to create regulate them in the airspace have been sluggish.

These rules aren’t the end of the drone debate. The agency still must integrate other classes of drones into the airspace. It also faces the challenge of enforcing the rules and resolving conflicting local and state drone regulations.

The new rules take down some barriers to drone flights, but there still are constraints in place.

Under the new rules, operators cannot fly during the nighttime, above 400 feet and within 5 miles of an airport. Those operators, according to the 624-page rulebook, must be at least 16 years old.

The rules do permit commercial transportation of goods with a drone, but the drone cannot fly beyond the line of sight. (Sorry, Amazon. It’s going to be a while before drone package delivery is a thing.)

Before Monday, a real-estate developer who wanted to take aerial photographs of a property with a small drone needed to obtain special permission from the FAA as well as pilot’s license. Now the FAA will allow operators to fly drones after passing an aeronautical knowledge test at an agency-approved facility and a background check with the Transportation Security Administration.

“This is a big barrier that’s going to be taken down to allow more commercial operators in the airspace,” said Tom McMahon, vice president of advocacy and public affairs for the Association for Unmanned Aerial Vehicles International, a trade group. “This is certainly welcome by the industry.”

With the barrier taken down for commercial flights of small drones, the industry is forecast to generate $82.1 billion in economic activity between 2015 and 2025, creating more than 70,000 jobs directly and indirectly, according to the Association for Unmanned Aerial Vehicles International. Maine’s share of the drone economy is projected to total $641 million over that same period, with 810 jobs created.

Not all drones, though, will benefit from the new rules. Chris Taylor, CEO of Gorham-based Viking Unmanned Aerial Solutions, said the operators flying drones for real estate, aerial photography and other industries for simple purposes, such as taking photographs, will be the most likely beneficiaries. That’s because their use most closely aligns with the content of the regulations.

Operators with more ambitious plans, such as inspecting pipelines, surveying farmlands and search-and-rescue operations, are restricted by line-of-sight and altitude requirements. Heavier drones also won’t benefit from these new rules.

That means these operators still need to meet more strict licensing requirements and obtain special permission — a section 333 exemption — from the FAA before they can fly, Taylor said.

Rules to integrate large drones and Amazon’s delivery fleet could emerge within the next couple of years, according to a spokesman from the FAA, but it could be a while before they are ready.

Now the FAA needs to enforce the new rule, and that could prove a tall order.

Since Congress under a 2012 law tasked it with integrating drones into the airspace, the FAA has maintained that it was illegal for operators to fly a drone for commercial purposes, unless the operator obtained an exemption.

Even with the claim of illegality, the FAA never pursued an enforcement action against an operator for failing to get an exemption. With no regulations in place for drone use, the FAA had little legal ground on which to penalize these operators unless they flew in a “reckless manner.”

Now that the new rules have kicked in, the FAA has authority to bring order to the Wild West of drone aviation.

“The further we get into this and the more regulations it passes, the more it codifies that in terms of public safety in the national airspace the FAA has the authority to do what it wants to regulate drone use,” Michael Bosse, an attorney and member of the drone law team at the Portland law firm Bernstein Shur, said.

But can the FAA effectively police a sky full of small drones?

Just consider this: An estimated 700,000 drones were sold in the U.S. last year, according the Consumer Technology Association, and as many as 1 million more could be sold this year. All those drones — whether they’re flown commercially or for fun — need to be registered with the FAA. Yet, since last December, only about 530,000 drones have been registered in the federal database, according to an FAA spokesman.

For a little perspective, that’s more than the approximately 320,000 aircraft registered with the agency.

“The capability [of the FAA] to police them in any systematic way is going to be difficult,” Bosse said.

All those drones can pose a potential hazard. Between Dec. 17, 2013, and Sept. 12, 2015, there were at least 921 reports of drones flying too close to airplanes, many of which occurred at heights above 400 feet and within 5 miles of an airport, according to an analysis by the Center for the Study of the Drone at Bard College in New York.

At least three minor incidents were reported in Maine last year — one north of Bangor International Airport and two at the Portland International Jetport.

That concerns local and state governments, many of which have started to regulate drones within their jurisdictions.

Last year, 15 states — including Maine — passed laws prohibiting certain bothersome drone activities, according to the National Conference of State Legislatures. Those particularly irksome behaviors states sought to rein in include using drones to harass hunters (read: PETA drones), flying over crime scenes and flying near prisons, nuclear plants and other “critical facilities.”

The Maine law that made the books prohibits police from flying drones as part of an investigation unless they obtain a warrant. A second bill that would have barred drones from flying over private property without permission died in committee over concerns it would conflict with the FAA’s regulatory authority in the airspace.

No towns have yet to adopt ordinances restricting drone use within their limits. But the town of Kennebunk is exploring creating a drone no-fly zone over more than a dozen public parks as well as some public beaches.

The FAA asserts it alone has the authority to regulate activity in the airspace. Last December, the agency issued a memo warning that local and state officials risked creating a “patchwork quilt” of regulations that would “severely limit the flexibility of the FAA in controlling the airspace … and ensuring safety and an efficient air traffic flow.”

Even with those concerns, the FAA stopped short of a full pre-emption of local and state drone regulations, saying in its commercial drone rulebook that “certain legal aspects concerning small UAS use may be best addressed at the State or local level.”

Eric Conrad, a spokesman for the Maine Municipal Association, said this signals that the FAA has recognized that local and state officials likely will be responsible for taking action against drone operators who pose a threat or nuisance to the public.

“The reality is this,” Conrad said. “If someone is flying a drone recreationally or commercially and it bothers someone, they aren’t going to call the FAA. They’re going to call the local police department or town manager.”