An unmanned remote-controlled helicopter that can spray crops or apply fertilizer has been given approval for test use in the U.S. by the Federal Aviation Administration.

Similar unmanned aerial vehicle (UAV) helicopters have been used in Japan for many years, basically for rice production, which is grown in small plots similar in size to a lot of specialty crop field production in the U.S.

The approval for use by the FAA reportedly was issued under a Section 333 exemption that regulates commercial use of unmanned aircraft. The helicopter approved is a Yamaha Corp., U.S.A. product—the RMAX. This particular helicopter is being approved for use in various countries.   

Ars Technica reporter Sean Gallagher provided specifics on the helicopter. “The RMAX is not a drone, at least in the sense that many think of them—it's a giant remote control helicopter controlled by a pilot within line of sight, weighing 141 pounds and capable of carrying 61 pounds of liquid spray or granules for crop dusting. The radio-controlled craft is powered by a 21-horsepower two-stroke engine—essentially a riding lawnmower engine.”

University of California Davis agricultural engineers are familiar with the RMAX and have been quoted as suggesting the UAV helicopter is suitable for use in many types of California operations but especially vineyards on rolling countryside.

The RMAX is not for autonomous operation in that it is not approved for flying without the ground pilot operating it within line of sight.