The Obama administration unveiled landmark rules on Tuesday that will open the skies for low-level small drones for education and research purposes, but unmanned commercial aircraft deliveries from companies like Amazon.com Inc. and Alphabet Inc. will require separate regulation.

The head of the U.S. Federal Aviation Administration, Michael Huerta, declined to offer a timetable on when those separate rules would be written. Until now, commercial drone operations had been illegal in the United States without specific FAA permission.

Drone flights will be approved for agriculture, research and development, educational and academic use, powerline, pipeline and antenna inspections. They also include aiding certain rescue operations, bridge inspections, aerial photography and wildlife nesting area evaluations.

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The new rules that take effect in late August allow drones that weigh less than 55 pounds and fly up to 400 feet high and 100 miles per hour, but only within sight of an operator and not over people.

Drones will not be allowed to fly at night unless they have special lighting and must stay at least 5 miles away from airports.

Operators must be at least 16 and have a remote pilot certificate and must report to the FAA of any drone that results in serious injuries or property damage.

"As this new technology continues to grow and develop, we want to make sure we strike the right balance between innovation and safety," said Transportation Secretary Anthony Foxx on a call with reporters.

The rules may still boost drone manufacturers such as SZ DJI Technology Co. and PrecisionHawk.

The White House says unmanned aircraft could lead to $82 billion in economic growth by 2025 and support up to 100,000 jobs.

Drones are increasingly important. The White House noted that the U.S. Interior Department has used unmanned aircraft systems since 2009 in conducting wildlife and vegetation surveys to protect endangered populations and wildfire management.

But drone flights will still remain banned in Washington, DC, because of security restrictions imposed by Congress.

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"We are in the early days of an aviation revolution that will change the way we do business, keep people safe, and gather information about our world,” Obama said in an interview with Bloomberg News.

The FAA in December announced rules requiring registration of drones weighing more than 0.55 pounds and less than 55 pounds including payloads such as on-board cameras.