A waterbomber is an aircraft that is equipped to drop large amounts of water from the air onto a target, usually a fire. Very commonly used in Canada and Russia for fighting forest fires that threaten human settlement or economic resources (forest lumbering areas), waterbombers provide firefighters the ability to attack fires in remote areas with amazing speed and accuracy. Most modern waterbombers are amphibious aircraft, able to land on sufficiently large lakes, fill their tanks and then return repeatedly to the fire zone. Other aircraft that have been adapted to the role of firefighting, like airborne fuel tankers, require filling at staging areas. Waterbombers are an important part of a coordinated wilderness fire response. Used in conjunction with ground based fire teams and spotter aircraft, they can make short work of hotspots and save many lives.

Carl Crossley and the advent of Canadian Waterbombing

During the 1940s, a pilot-engineer from the Ontario Provincial Air Service, Carl Crossley, was stationed at the Temagami Ontario forward fire base. Flying spotter planes, Crossley thought of the idea of dropping water from the air, like the military aircraft of the time carried large loads of bombs to drop on enemy forces. Testing his theories, Crossley used small floatplanes that he would land on the surface of lakes. Forcing water into the planes tanks on landing proved ineffective and dangerous, so he switched to pumping water into barrels. The problem then became getting the water from the plane to the fire. Dropping the water with any degree of accuracy proved very difficult.

Deciding that he needed a larger reservoir of water, Crossley got the idea of taking water directly into the planes floats. The problem was that the single hulled floats that the planes used are a lot like a boat. Filling a float with too much water could mean unbalancing the plane, making you too heavy for liftoff or even sinking the plane. No way of measuring the amount of water taken in was available and no means of remotely dumping the floats existed. Crossley forged ahead and manufactured a set of floats based on his detailed designs. Crossly had his floats fitted to a Noorduyn Norseman aircraft which he then equipped with water pickup and bombing controls. Using his custom plane, Crossley successfully attacked a fire near Temagami, Ontario in August 1945. Only carrying about 100 gallons of water, which took nine seconds to dump, Crossley was able to knock the fire down and give fire crews time to arrive on the ground. His first prototype was a limited success.

The largest obstacle that Carl Crossley faced was not the mechanics of dropping water from a plane. It was the politics of changing the role of the fire air service. OPAS didn't share his enthusiasm for the concept. Leaving the OPAS , Carl tried to market his idea to the Canadian Federal Government. Little action was taken, but the concept was given thought. The Air Service though kept up some related experiments during the late 40s and early 50s. After many various failed attempts, from actual water-filled plastic bombs to pilot-operated fire hoses. Tom Cooke, another OPAS pilot, firmly believed that Crossley's idea had merit.
Cooke, working from Crossley's ideas, joined up George Gill, an OPAS air engineer. They mounted open-top tanks mounted on front of each float. These roll tanks could be easily filled by simply moving the aircraft rapidly along the surface of the water, in landing or take-off maneuvers. After dumping, the tanks returned to the filling position for reuse. The first aircraft to be outfitted with the system were single-engined Dehavilland Beavers, each carrying about 80 gallons of water. Soon larger rollover tanks were developed for the Dehavilland Otter including a 210-gallon belly tank.

In 1957, Cooke tested his new system on a remote fire in the Sudbury Ontario Fire District. His Otter was able to hold a strip of fire about one mile long until the ground crews could attack from the ground. Without the aerial waterbombing, the fire would have quickly grown into unmanageable proportions. This success, as well as the increasing power of civilian aircraft, lead to a change of heart in the OPAS about aerial firefighting. Carl Crossley's dream of aerial firefighting through waterbombing was had finally come true.

Modern Waterbombing Equipment

Canada

Bombardier Aerospace of Canada now supplies the Canadian Department of Natural Resources and Provincial Air Services with the new Canadair 415. It is the latest in a line of multi-role amphibious aircraft beginning with the CL-215 in the 1960s. It features a four-compartment, four-door water tank system that can hold 6137 litres (1621 US gallons) of water/foam mixture and refills its tanks by skimming the surface of any suitable body of water for a total of 12 seconds. Using this method, the CL-215 can drop 54140 litres per hour, when 11 km from fire. Not bad for only $35 million Canadian a pop.

United States

The unique demands of fighting fires in California gave rise to the Erickson Helitanker. Large bodies of water, other than the ocean, are not available in some areas. The Erikson, which is a waterbombing helicopter, solves this problem. It can deliver 7,500 litres (2,000 gallons) of water in one drop, and refill from any water source 45 cm (18 inches) deep in about 45 seconds using a system of pumps and hoses. The Helitanker can precision deliver 110,000 litres (30,000 gallons) per hour using this method.

Military aircraft can also be retrofitted to waterbombing roles. It was popular in the southern United States to adapt surplus military cargo planes and bombers from World War II into waterbombers. These craft where filled at airbases with fire retardant foam and then used to fight remote fires. Currently, other aircraft, such as the C-130, Martin Mars and DC-6 are still used.

Russia

The Ilyushin-76TD is the world's largest waterbomber. The turbofan powered Il-76 started its life as a massive Soviet bomber refueler. After being pressed into a waterbombing role, it proved a useful tool. It can reach a fire anywhere in the world within 12 hours. Carrying 42,000 litres (11,000 gallons) of water and fire retardants, 4 times as much as a C-130, it can, in one run, dump enough water to cover 6 double-wide football fields, or an area 1.1km (0.7 miles) in length.

What is it like to see one working?

As a child I saw CL-215s in operation from up close on several occasions. Living in a more heavily wooded area of the province, summer lightning strikes and hot dry conditions would sometimes start fires close to the town I lived in. The billowing smoke and low flying spotter planes always turned a town threatening fire into a spectacle. One particular time, when a fire was very close to a road that my friends and I rode our bikes on, I got a front row seat to a waterbomber in action. My friends and I were close enough to see the flames on the tops of the trees about 150 yards away when we first heard the bright yellow painted bomber. With full tanks, it makes a deep loud roar as the props struggle to keep all that plane and water in the air. Flying tree top level, the huge doors opened up and a huge white cloud dropped like a fog, making a loud hissing sound. As the plane pulled up, the water hit the burning trees. A big strip of fire clicked off like a light and a lot of closer trees snapped and bent. A huge whump sound followed. The black smoke of the fire was replaced by clouds of white stream. A fine cool mist that smelled of lake water covered my friends and I. Several more runs made short work of the section of fire closest to the houses on the road. It was the coolest thing I saw that summer.


Sources
-Ontario Provincial Air Service
-Google
-Bombarier Aerospace

Log in or register to write something here or to contact authors.