CLAYTON (KPIX 5) – One of the reasons firefighters battling the Marsh Fire were able to save several seriously threatened homes was the massive Cal Fire tanker swooping down from the sky to drop retardant.

The new Cal Fire 747 can go anywhere in California on short notice. KPIX 5 traveled to a Cal Fire air base in Sacramento Thursday to get a closer look at the “Global Supertanker.”

McClellan Air Force Base became a civilian airfield when the military left in 2001. But battles are still being fought out of the base every day.

“This is where Cal Fire reloads large and very large air tankers for Northern California,” said Cal Fire Public Information Officer Brice Bennett.

The “very large” air tankers include several DC-10s, one of which was seen heading off to help fight the Cranston Fire burning in Riverside after getting a fresh refill of retardant.

But as large as the DC-10 might be, Cal Fires new took gives a new definition to heavy fire equipment.

Dubbed the “Global Supertanker,” the retired 747 airliner has become the largest horse in the Cal Fire stable.

The cockpit looks the same, but a fuselage that once held more than 600 passengers has had all the seats removed and now holds pressurized tanks filled with 19,000 gallons of retardant. When the Supertanker lets loose as it did at the Marsh Fire burning near Clayton, it can lay down a fire line more than a mile long.

“When we need a large amount of retardant in a very short amount of time, this aircraft is definitely the tool for the job,” explained Bennett.

The 747 is also the fastest plane in the force, flying about twice the speed of your normal airliner. It can return from Southern California for a refill in Sacramento in about 45 minutes.

“This aircraft is capable of delivering 19,000 gallons of retardant anywhere in California at over 600 miles per hour to get to the scene. That’s very fast,” said Bennett.

The base itself is strategically located for heavy tankers to respond to both the northern and southern borders of the state.

The Cal Fire air fleet will soon be expanding, with up to seven of Coast Guard C-130’s set to be retrofitted for use by Cal Fire. With changing weather patterns allowing wildfires at any time of year, officials say there’s no such thing as “fire season” any more.

“Times are definitely changing. We’re seeing larger and more destructive wildfires year-round,” said Bennett. “We’re bringing in different tools, larger tools to fight these wildfires.”