WASHINGTON — The government has the power to hold drone operators accountable when they operate the remote-control aircraft recklessly, a federal safety board ruled Tuesday in a setback to small drone operators chafing under Federal Aviation Administration restrictions.

The National Transportation Safety Board, which hears appeals of Federal Aviation Administration enforcement actions, ruled that small drones are a type of aircraft and fall under existing FAA rules.

The FAA had fined Raphael Pirker, an aerial photographer, $10,000 for operating his Ritewing Zephyr in a reckless manner on the University of Virginia campus in 2011. Pirker allegedly flew the drone, which weighed less than 5 pounds, at “extremely low” altitudes, including under a pedestrian bridge and directly at a person, causing the individual to duck out of the way. He had been hired to make photos and videos of the campus.

Pirker appealed the fine, saying his aircraft was effectively no different than a model aircraft and therefore not subject to regulations that apply to manned aircraft. An NTSB administrative law judge sided with him in March, saying the FAA hasn’t issued any regulations specifically for drones and therefore can’t determine their use.

The FAA appealed the decision to the four-member safety board, which said Tuesday that the definition of an aircraft is very broad.

“An ‘aircraft’ is any ‘device’ ‘used for flight in the air.’ This definition includes any aircraft, manned or unmanned, large or small,” the board said. The board sent the case back to the judge to decide if Pirker’s drone was operated recklessly.

The FAA said in a statement that Pirker operated the drone “in a careless or reckless manner” and the fine “should stand.”

The decision strengthens the FAA’s position as the agency tries to cope with a surge in use of unmanned aircraft, some available for purchase on the Internet and in hobby shops for as little as a few hundred dollars.

More than a million small drone aircraft have been sold worldwide in the past few years, and a growing number of them are turning up in U.S. skies near airports and airliners, posing a risk of collision.

Reports of drone sightings near other planes, helicopters and airfields are reaching the government almost daily – a sharp increase from just two years ago when such reports were still unusual.

A wide array of industries as varied as real estate agents, farmers and major league sport teams are clamoring to use small drones. Amazon wants to use drones to deliver small packages to customers.

Congress directed the FAA to safely integrate drones of all sizes into U.S. skies by the fall of 2015, but it is clear the agency won’t meet that deadline.