A drone the size of a small Cessna plane buzzing over the massive Rim fire has become a valuable tool as commanders use its real-time imagery to strategize their next move.
The remotely piloted plane began flying Wednesday morning after Incident Cmdr. Mike Wilkins requested the MQ-1 aircraft belonging to the California Air National Guard. It has since been giving fire commanders a bird's-eye view of the 300-square-mile blaze in and around Yosemite National Park, which is now the sixth largest fire in state history.
Unmanned aircraft have been used sparingly on fires but are gaining value as a cheaper, more efficient tool for fire commanders to better understand how fires are behaving.
They are prized for their ability to beam real-time pictures directly to fire commanders, who can make tactical adjustments more quickly. The aircraft are equipped with infrared heat sensors and a swiveling camera operated remotely.
During a 20-hour mission Wednesday, the drone -- taking off from the Victorville airport and operated from March Air Reserve Base in Riverside -- alerted crews to a spot fire and provided a more comprehensive fire map.
Unlike manned planes and helicopters, drones are not grounded at night or unable to fly in high winds or smoke. They fly at about 18,000 feet and cost about $800 an hour to operate, Keegan said.
There are now 4,840 firefighters battling the Rim fire, which has been burning in the Stanislaus National Forest for nearly two weeks.
The blaze is 30% contained and has cost nearly $40 million to fight so far, officials said. The fire has burned about 301 square miles, an area bigger than Chicago or San Francisco, and destroyed at least 111 structures.
Fire crews in Yosemite were hoping to slow advancing flames by conducting large-scale backfire operations from Hetch Hetchy Reservoir south to Tioga Road.
The rate of spread of the massive fire has slowed in recent days and firefighters expect to have it fully contained by Sept. 10, officials said.