Agricultural use of drones is about to take off in the U.S. after being grounded for years by the lack of federal guidelines.
The small, relatively inexpensive vehicles could replace humans in a variety of ways: transmitting detailed information about crops to combines and sprayers, directing them to problem spots and cutting down on the amount of water and chemicals that a farmer needs to use in those areas.
The Association for Unmanned Vehicle Systems International, a trade group, says agriculture could account for 80 percent of all commercial drone use.
The Federal Aviation Administration has approved more than 50 exemptions for farm-related operations since January. Companies with those exemptions say business has grown, helped by quick advances in the technology.
Bret Chilcott of AgEagle, which sells unmanned aerial vehicles and the software to help operate them, says his company took its first orders last year. Now it has a backlog of several hundred orders.
"Last year, users had to land their aircraft and then take the data to the computer," he says. "Now the data appears on your iPad or hand-held device a few minutes after flight."
That data could be pictures, 3-D images of plants, thermal readings of crops or animals or other observations. Information that in the past took days to collect, or could not have been collected, can be gathered now in minutes or hours. In some cases, it can be integrated with data collected from other high-tech farm machinery.
"In five years, we won't have to blanket a field with chemicals," Chilcott says.
Still, most farmers cannot legally fly the vehicles yet.
The FAA is working on rules that would allow the drones to be used regularly for business while maintaining certain safety and privacy standards. An FAA proposal would allow flight of the vehicles as long as they weigh less than 55 pounds (24 kilograms), stay within the operator's sight and fly during the daytime, among other restrictions.
Operators would have to pass an FAA test of aeronautical knowledge and a Transportation Security Administration background check.
Pilots of crop dusters and other planes that operate around farms are concerned the rules do not go far enough to ensure safety.
"We can't see them," says Andrew Moore of the National Agricultural Aviation Association. His group advocated for the unmanned vehicles to include tracking systems or lights to help airplanes figure out where they are, but that was not included in the proposal.