The modified 747 is equipped with a 24,000-gallon tank and a pressurized system that can shoot flame retardant at high pressure or simply disperse it while flying over a fire.
Unlike helicopters that can hover above a fire, the 747 must approach at 140 knots and pass between 400 and 800 feet above the flames to deliver its massive load.
The wide-body jet airliner in use for fire service, the DC-10 used by Cal Fire used to fly for Pan Am and American Airlines. It can carry 12,000 gallons of flame retardant that, when dispersed, creates a cloud 300 feet wide and a mile long.
According to Cal Fire, one DC-10 drop is equivalent to 12 drops from an S-2 air tanker. Because of its size and the infrastructure needed to support its operation, this jet is only used for extended missions.
Known for its speed and maneuverability, the S-2T was a U.S. Navy anti-submarine warfare airplane in a past life. Cal Fire now has approximately two dozen of the turboprops in its arsenal. The aircraft can cruise at speeds of 305 mph with a 1,200-gallon payload commonly used for initial attack delivery.
Dubbed the "Super Huey," the UH-1H was once used by the Army for troop and cargo transport operations. Now heavily modified, the choppers can do it all: crew transport, water and foam drops, medical evacuations backfiring operations and infrared mapping.
CL-215/ Bombardier 415 "Superscooper"
Nicknamed the Superscooper, these seaplanes scoop water from lakes and reservoirs into their belly that can be directly dropped onto flames or mixed with a foam retardant. The Bombardier model can travel at more than 200 mph with 1,621 gallons of water on board.
Sikorsky S-70 "Firehawk"
The Firehawk is a civilian version of the well-known Blackhawk helicopter commonly used by the United States Army for air assault missions. The aircraft can either be used with a large 1,000-gallon tank mounted on its belly or with a bucket.