What do you get when you combine an aircraft created specifically for agricultural work and amphibious floats designed specifically for firefighting operations?
You get the FireBoss, which may be the most efficient firefighting aircraft in use today, or so says Charlie Wiplinger, director of research and development for FireBoss LLC.
“We built the FireBoss based on the Air Tractor 802,” says Wiplinger, whose family company, Wipaire, Inc. of St. Paul, Minn., has been designing aircraft floats for more than 46 years.
The concept of adapting floats to fit the AT-802 for use in fire suppression was a natural fit, he says.
“The aircraft is the most widely used in firefighting applications,” he explained. “It has the best useful load of all the airplanes we looked at.”
The Air Tractor was float certified five years ago, according to Wiplinger. “Many years, perhaps 10 before that, Leland Snow from Air Tractor called my dad, Bob Wiplinger, about the idea of creating a float for the Air Tractor,” he says. “Dad said he’d think about it, then Leland called him back and said ‘forget it, I don’t think it will work.’ Dad went ahead and did it anyway, eventually creating the FireBoss.”
The Air Tractors are mounted on specially designed amphibious floats. The floats have water intake scoops (also known as probes) on the keel that allow them to take in water from a lake or river. The tanks also can be loaded with concentrated fire suppression foam that is mixed with water.
“The floats are a version of the large floats that we produce for Twin Otters,” Wiplinger says. “We shortened them up and added the scooping system. The probes are retractable and located just forward of the main wheel on each float. The scoop or probe actually rotates down and there is a hole. When you touch down on the water you can fill up the hopper in about 10 seconds.”
“That’s about 800 gallons in 10 seconds, as you are taxiing on step,” notes Stan Ross, global product manager for FireBoss.
“You are taxiing at about 65 knots,” Wiplinger adds. “You want to have enough speed so the drag of the scoops does not slow you down so that you come off the step. Usually this is not an issue. Then when the tanks are full, you lift off again.”
LEARNING TO FLY THE FIREBOSS
“The FireBoss flies the same as a conventional floatplane right up to the point where you deploy the probes,” notes Mark Mathisen, chief pilot and director of FireBoss training. “The probe deployment creates a high amount of drag and there is a pitch recovery moment when you put the probes down. You need to pull back on the stick.”
The pilot activates the probe deployment by pressing a button on the stick. As long as the pilot’s finger remains on the button, the probes are deployed.
“There is a scoop computer that you can run,” he says. “The computer allows you to select between 350 and 800 gallons on a rheostat. When you get to the predetermined amount the computer shows you the level in the tank and you let up on the trigger and the probes retract. When you do that you simultaneously add takeoff power and lift off. It takes about 12 seconds to gather a full load.”
Mathisen notes that for pilots who already have some floatplane experience it takes about 10 hours to get proficient in the FireBoss. The greatest challenge, he says, is the weight change between flying an aircraft with an empty hopper versus one that is full of water. “It’s a lot heavier and it handles like a whole different airplane when it’s full,” he says. “That takes some getting used to. Like any other large floatplane, the probe deployment creates a high amount of drag. The main thing is for pilots to get proficient enough to land with the probes all the way down and to only have to do one pitch recovery. That saves time.”
Time is of the essence when you are fighting a wild fire, adds Ross.
“What makes the FireBoss unique is that it can increase cycle times on a fire,” he says. “The FireBoss can work on unimproved fields and load up at a standing fire base, drop its load, then reload over a lake or river and make multiple attacks before other aircraft have even launched. So in terms of dispatch, reliability and speed, the FireBoss is proving an effective tool. It won’t replace the large tankers, but it is a fantastic supplement to their capability.”
The aircraft has a good track record in Europe and Canada, notes Ross.
“But this fire season is the first time it has been used in the United States,” he says. “The state of Minnesota is the first to have a contract for the use of the FireBoss. We’re glad that the first time the FireBoss is being used in the U.S., it’s in our home state.”
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