Firefighting planes were temporarily grounded in San Bernardino amid powerful winds

SAN BERNARDINO, Calif. (KABC) -- At San Bernardino International Airport on Monday, all fixed-wing firefighting aircraft were temporarily grounded even as major wildfires continued to burn in Southern California.

Winds were simply too powerful to allow the planes to effectively contribute to the firefight amid the severe weather conditions.

"Where we really get into some more dangerous situations for our aviators is when it's gusty," Cal Fire Air Operations Branch Director Sean Ryan, a spokesman for the agency, told ABC7. "Sustained winds, they're able to fly through those a little bit more predictably. But when we have high-gust spreads it becomes a lot more dangerous for those folks."

It's not that these aircraft can't fly when it's this windy, it's that they can't make effective drops, Ryan said. When sustained wind speeds are more than 30-40 knots -- or about 34-46 mph -- it's too difficult to drop fire retardant and effectively hit a target.

"When we start dropping the retardant and we start dropping the water, and the wind takes that water and disperses it in an area we don't want it to be, or it basically turns it into a mist, then we're just not effective," Ryan said.

According to officials, the plane collided with a privately-owned drone, causing significant damage to it.

Water-dropping helicopters were still flying on Monday. When it comes to them, because they can fly lower and more slowly, it's more of a situation where it's up to the pilot -- not a specific wind-speed threshold.

"What that actually does is it slows fire progression, it makes fire-intensity lesser, so those boots on the ground can actually come in, extinguish the fire, protect the structures and save lives and property that we're all here to do," Ryan said.