Story highlights The 4½-foot-long aircraft aims to survey equipment and roads at Prudhoe Bay, Alaska, oilfield

The drone's flight was the first such commercial flight approved over land

Last summer, the FAA authorized drone flights over Arctic waters

The FAA is seeking to safely integrate drones into national airspace

A drone that just started flying for energy giant BP in Alaska is the first commercial drone operation authorized over land by the Federal Aviation Administration, the agency announced Tuesday.

The FAA said Tuesday it approved BP's plan for an unmanned aircraft system to survey roads, pipelines and other equipment at Prudhoe Bay, Alaska, the largest oilfield in the United States.

The drone's manufacturer, AeroVironment, conducted its first flight for BP on Sunday, the FAA said, but the flight of the 4½-foot-long aircraft wasn't disclosed by the FAA until Tuesday morning.

It was the first such commercial flight authorized over land. Last summer, the FAA authorized drone flights over Arctic waters.

The FAA has greatly restricted the commercial use of drones over U.S. land and water as it seeks to safely integrate them into national airspace. Entities that fly drones must first get certificates of authorization, and those have gone chiefly to government enterprises and those conducting research.

Under AeroVironment's certificate, the company can operate only in daytime, where there is a visibility of 3 miles, and the aircraft must be kept in sight. The company must also notify air traffic controllers.

Last week, the FAA announced that Nevada will host the third of six congressionally mandated drone research sites. The FAA granted the Nevada team a two-year certificate to use an Insitu ScanEagle at the Desert Rock Airport in Mercury, Nevada. Desert Rock, owned and operated by the Department of Energy, is a private airport and not for general use.