OAKVILLE To some, the sight of a small helicopter hovering a few feet over a Napa Valley vineyard may be just a curiosity.
To others its the future of California farming.
One of those is Ken Giles, professor of agricultural engineering at UC Davis.
In Giles' mind, agriculture has as much to do with unmanned vehicles as it does with tractors and threshers.
At the university's research vineyard Wednesday in Oakville, Giles showed off one of those vehicles a 200-pound RMax helicopter built by Yamaha. In flight the helicopter revealed surgical and lighting-fast movements over the vineyard.
In conducting such flights, Giles and his team are gathering data and weighing the feasibility of the unmanned helicopters for pesticide use.
Wednesday's flight was done with water instead of the pesticides.
The Federal Aviation Administration does not allow pesticide spraying from unmanned helicopters as it considers them "experimental" vehicles.
Giles expects the FAA will make a ruling as early as 2015 on the future of unmanned helicopter use. "In the U.S. right now there is no commercial use of this technology it's strictly a research and development effort," he said.
UC Davis is one of five universities in the United States researching the use of the helicopters for agricultural purposes. It's the only one looking into using them for pesticide use.
The entry point for the helicopters will be to use them on hillside farms, Giles said.
"The unmanned helicopter technology allows precision positioning," the professor said. "Plus, the hillsides are hazardous and time-consuming to drive and spray for a tractor."
On Wednesday, the helicopter offered a dance of precision as it hovered, then sped past row over row of vines to a top speed of 12 mph. It simulated the spraying of pesticide from two of its 2-gallon tanks. The whir of the rotor blades lightly disturbed the vines as if they were being whipped up by a storm.
Giles said that a tractor working the vineyard would have moved at a 3 mph clip, with maneuverability limited between rows.
The helicopter's operation demands a crew of two a pilot who controls the helicopter with the same type of joystick console used by hobby aircraft fliers and a spotter who directs precise movements.
A recent study by the Association for Unmanned Vehicle Systems International contends the agriculture industry would be the largest market for unmanned helicopter technology. Giles said he has been working with almond farmers in the Lost Hills area of Kern County, who are eager to use the technology for pesticide spraying.
While new to California, the use of unmanned helicopters on farms is not new.
Unmanned helicopters have been in use in Japan for the last 20 years, said Yamaha helicopter pilot Steve Markofski.
There are 2,500 RMax helicopters in use over 2.5 million acres of Japanese rice farms, according to Yamaha. The government introduced them into the Japanese agricultural industry to address an aging farming population.
Unmanned helicopters also are on their way to being approved for use in Australia, mainly for weed control. In the agricultural community of Flowerdale, about 70 miles north of Melbourne, Australia, the RMax helicopters have been tested on Terry Hubbard's blackberry farm. Typically, Hubbard uses manned helicopter sprayers to apply pesticides.
"Of the total of 2,100 acres, blackberry infestation would barely cover 100 acres, but they're scattered clumps, and hard to access because of the hilly nature of the farm, hence the need for aerial control," Hubbard said via email.
Hubbard said the unmanned helicopter technology is still too expensive to use exclusively. Harvesting about 4 gallons of blackberries would cost him roughly $800 in pesticide-spraying costs, he said.
"This is significantly dearer than a conventional helicopter," said Hubbard.
He contends that one of the brightest benefits of using unmanned helicopters is environmental. "It must be remembered that the ability to target clumps of blackberry with minimal overspray means that chemicals go further, and non-target species are avoided."
Hubbard said that there is ample evidence near his farm of widespread tree damage where chemicals are applied by boom sprayers from conventional helicopters.
For Giles, a hybrid of manned and unmanned aircraft would be the best use to safeguard the environment. "A big aircraft could spray the middle of a field and then an unmanned one can fly low and spray the boundaries."
Giles said the rapidity of the unmanned vehicles would give farmers time to see if pesticide application is even needed. The time-consuming nature of manned vehicle spraying requires farmers to decide early on whether to spray a field to save a crop, he said.
Call The Bee's Edward Ortiz, (916) 321-1071. Follow him on Twitter @edwardortiz.