At least five large wildfires are burning in California - and the worst part of the fire season is actually just beginning. Red flag warnings are posted throughout the state.

California has a top weapon for battling its biggest fires. Firefighters battling California’s largest wildfires call it their big gun.

“When you’re up here trying to save lives and property, it’s pretty intense!” says R.K Smithley, the pilot of a DC-10 passenger aircraft that’s been transformed into a powerful weapon against flames. “Somebody that was very smart, way smarter than me, decided ‘Let’s put three tanks on a DC-10!’”

The DC-10 is being called the “big guns” used to fight California wildfires. CBS Evening News

Together - those tanks carry more than 11,000 gallons of fire retardent, about nine times more than any other plane in the fleet. All three tanks can be rapidly refilled.

“Twelve to 15 minutes, these babies are full and we’re gone!” Smithley says.

What makes this plane unique isn’t just its payload, but also how it’s flown: Making fighter style turns - just 250 feet above the ground.

You don’t expect to see aircraft flying like this.

“We fly this in some amazingly tight spaces,” Smithley says.

Spaces firefighters often can’t reach from the ground.

There are at least five large fires burning in California as fire season begins. CBS Evening News

Without that air support, “we’d see a lot bigger fires! We’d see a lot more rapid growth, we’d see fires lasting longer, consuming more ground resources,” Smithley says.

Smithley says he knows how critical his job is.

“People on the ground are relying on us doing it right,” Smithley says, giving the thumbs up. “That’s what it’s about, right there!”

That thought is top of mind, he says -- every time he makes a drop.