FAA Plans Ground Amazon's Drone Program Guidelines could prevent the company from launching Prime Air service in the U.S.

Amazon's proposed delivery service hit some significant turbulence Sunday with proposed new rules for drone operation from the Federal Aviation Administration and Department of Transportation.

If passed as initially outlined, the guidelines could prevent the company from launching the service in the U.S.

Under the draft of the regulations, drone operators must remain within a visual line of site from their drones and are not allowed to fly drones over people who aren't in control of the aircraft. The rules are bad news for Prime Air, which Amazon had previously showcased using autonomous drones that were not manually operated by staffers.

Amazon, though, said it is still committed to delivering packages to customers via drones, and called on the government agency to rethink its proposal and how it might impact corporations.

"The FAA needs to begin and expeditiously complete the formal process to address the needs of our business, and ultimately our customers," said Paul Misener, Amazon's vice president for global policy, in a statement. "We are committed to realizing our vision for Prime Air and are prepared to deploy where we have the regulatory support we need."

The rules also limit the weight of an unmanned aircraft to under 55 lbs. Amazon had previously said the initial weight capacity of its drones would be limited to 5 lbs.

The FAA released the proposal for rules regarding drones on Sunday. The agency stressed that the proposals are not final, and that it is seeking input from all interested parties.

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

The FAA is accepting public comments on the proposed regulation for the next 60 days. Among the areas it specifically mentioned as being up for discussion: whether the rules should permit operations beyond line of sight, and if so, how far operators would be able to fly drones.

Amazon had previously hoped to launch Prime Air in 2015, although that date was always dependent on regulatory approval, and even Amazon CEO Jeff Bezos called it "optimistic." Now the language on the service's page is much more ambiguous, saying "Putting Prime Air into service will take some time, but we will deploy when we have the regulatory support needed to realize our vision."

Amazon initially unveiled Prime Air and its drone delivery ambitions in 2013 as part of a broader effort to further speed up deliveries. In announcing the program, Bezos said the drones could deliver packages within a 10 mile radius of the company's fulfillment centers within 30 minutes.

Amazon is not the only company looking to drones as possible delivery systems. Google, Domino's Pizza and Alibaba have also been conducting trials.