(NVR) - A new way to protect grapevines from disease, delivered from above, is taking flight over Napa vineyards.

On May 18, a vineyard owned by Venge Vineyards in Calistoga was the site of the first U.S. commercial crop spraying by unmanned aerial system, according to a news release from Yamaha Motor Corp.

The company makes small-sized helicopters that are flown via remote control over vineyards to apply chemicals on the crops below.

Yamaha’s remotely piloted helicopter, called the RMAX, is different from drones that hobbyists typically fly, said Brad Anderson, a market development manager for Yamaha’s Unmanned Systems Division.

Instead of a camera, the RMAX features a 16-liter tank strapped on its side. It hovers around 10 feet above the vines to distribute the chemicals.

“All our flights are low and slow,” said Anderson. In fact, the rotor wash actually helps push the chemicals down into the fruit canopy.

The first Napa Valley flight was completed for Napa-based Silverado Farming Co. During its debut the RMAX applied a fungicide to control powdery mildew — one of the most common fungal diseases affecting grapes and many other crops.

For Yamaha, the U.S. debut of RMAX commercial services for the agricultural industry marks the culmination of several years working with the Federal Aviation Administration to receive appropriate certifications, as well as extensive field research with the University of California at Davis.