The government proposed long-awaited rules Sunday to usher in an era of commercial drones zipping through U.S. skies, but packages from these unmanned aircraft won’t be landing on doorsteps any time soon.

The Federal Aviation Administration (FAA) proposed requirements that commercial operators must meet, such as passing a knowledge test administered by the agency as well as a federal security check, in order to fly small drones, defined as weighing less than 55 pounds (25 kilograms). It is likely to be two or three years before the rules are made final, but federal officials said that once they are in place, the economic and safety benefits of unmanned aircraft are expected to be enormous.

Among the chores that officials envision drones performing: Aerial photography and mapping, crop monitoring, and inspections of cell towers, bridges and other tall structures. But the proposal includes safety restrictions such as keeping drones within sight of operators at all times and no nighttime flights. That could mean no package or pizza deliveries by drone. Drones would also have to stay at least 5 miles (8 kilometers) away from an airport.

Flights over people except those involved in the drone’s operation would be prohibited.

They could travel as fast as 100 mph (160 kph), but flights would be limited to 500 feet (150 meters) in altitude or below. Flights over crowds would also be prohibited.

“We have tried to be flexible in writing these rules,” said FAA Administrator Michael Huerta. “We want to maintain today’s outstanding level of aviation safety without placing an undue regulatory burden on an emerging industry.”

The agency is researching technology that he hopes will eventually enable small drones to fly safely beyond the sight of operators, Huerta said. He emphasized that introduction of commercial drones into the national airspace will be a staged process. The government is also looking ahead to how larger drones might be allowed to fly in airspace shared by manned aircraft, for example, he said.

One of the key safety concerns is that without a human on board the ability to “see and avoid” other aircraft is limited. Another concern is that the link between the operator and a remote control aircraft can be broken, causing the drone to fly away until it loses power or collides with something.

Cases of flyaway drones getting stuck in trees or hitting buildings are rampant. Last month, a drone that its operator lost control of flew over the White House fence and crashed on the lawn before Secret Service agents could block it.

Even with the restrictions, drones are expected to play a “transformative role in fields as diverse as urban infrastructure management, farming, public safety, coastal security, military training, search and rescue, and disaster response,” the White House said in a presidential memorandum on privacy released in conjunction with the rules.

The memorandum lays out measures federal agencies must follow to guard against abuse of data collected in their drone flights. Among other steps, the order requires agencies to review privacy and civil rights protections before deploying drone technology and to adhere to a range of controls. Personally identifiable information collected in drone flights is to be kept no longer than 180 days, although there are exceptions.

It’s questionable whether such steps will satisfy civil liberties advocates, who’ve objected strongly to the government’s vigorous use of digital surveillance in the name of national security.

The proposal also raises the possibility that final rules may have a separate category for very small drones – those weighing 4.4 pounds (2 kilograms) or less – with fewer restrictions.

Source: The Associated Press