Amazon.com is inching closer to a future where packages will be delivered by drone.
The online retail giant, which has been aggressively opening new distribution centers to shorten delivery times, was granted permission Thursday by the Federal Aviation Administration to test an unmanned aircraft design.
The "experimental airworthiness certificate" comes with several restrictions: Drones must be flown during the day and at 400 feet or lower; the aircraft must stay within sight of the pilot and observer; and the pilot must have, at minimum, a private pilot's license and current medical certification.
Amazon is also required to give the FAA a monthly update with information including the number of flights conducted, unusual malfunctions and any loss of communication links.
The Seattle company first dangled the futuristic Prime Air concept back in 2013, when Chief Executive Jeff Bezos said on CBS' "60 Minutes" that the service would be available for packages weighing in at 5 pounds or less.
A video posted on Amazon's website depicted a drone picking up a package at the end of a conveyor belt, then flying it across a grassy field before dropping the order outside a customer's doorstep.
The company promised then that its drones will one day "be as normal as seeing mail trucks."
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