In the mid-1940s, a pilot-engineer from the Ontario Provincial Air Service, Carl Crossley, was stationed at the Temagami base. It was during this time that Crossley hatched the idea that if military aircraft could carry large loads of bombs against enemy forces, why couldn't civilian aircraft bomb forest fires with loads of water?
Crossley's initial tests involved either an open cockpit biplane or a high-wing Stinson Reliant. In any case, he created an elaborate system of metal tubes, elbows and nipples to get the water from the source into the barrel, while the aircraft was moving along the surface of a lake. These efforts proved less than satisfactory until a firefighter suggested using a fire power pump and hose. While this was an efficient way to get the water into the barrel, dumping it from the air with any degree of accuracy proved disappointing more times than not.
Crossley didn't give up however. He got the idea of taking water directly into the floats. The problem here was that the floats of the day were not baffled or compartmentalized. A pilot attempting this manouevre ran the risk of filling the floats too full, and this could spell disaster. The two main problems were that the pilot had no way of knowing how much water was going into the floats, and had no way of dumping the load quickly. There were no hydraulic bomb doors for water load release.
Crossley realized what had to be done and a set of floats were converted based on his detailed drawings. Fitted to a rugged Noorduyn Norseman aircraft, complete with water pickup and bombing controls installed in the cockpit, Crossley was successful in attacking a fire near Temagami in August 1945. While only carring about 100 gallons of water, which took nine seconds to jettison, Crossley was able to knock the fire down and give fire crews a chance to get in on the ground and put it out.
Crossley's other problem was with air service management. They didn't share his enthusiasm for the concept. Shortly afterwards, he left the OPAS and tried to market his idea to the federal government. While they listened, little action was taken.
The Air Service though kept up some related experiments. Actual water bombs -- five gallon waterproof bags of water were dumped through the camera hatch of a piston Beaver in the late 1940s. Not much success there. And in 1946 the OPAS tried to convert a former twin-engined reconnaisance aircraft, a PBY-5A Canso into a heavy waterbomber. At that time, they were trying to fit it with external tanks. This aircraft was also converted to use as a forest spray plane, and was disposed of a year later.
But Crossley's initial ideas weren't forgotten by everybody. Tom Cooke, a former RCAF Canso pilot, and a pilot with the OPAS, firmly believed that Crossley's idea had merit. And he set out to prove it in the 1950s.
The idea of carrying a water-filled tank in the cabin of the aircraft, with the water load exiting through the side doors was quickly scrapped. Then, an air engineer named George Gill suggested they try open-top tanks mounted on each float.
These roll tanks could be easily filled by simply moving the aircraft rapidly along the surface of the water. A series of cables and pulleys allowed the pilot to dump the load and the tanks, weighted at the bottom, would automatically right themselves, ready for the next pick-up. Success at last.
The first aircraft to be outfitted with the system were the single-engined Beavers, each carrying about 80 gallons of water. Later, similar, larger rollover tanks were developed for the larger piston Otter aircraft, followed by the building of a single 210 gallon belly tank.
In the summer of 1957 Cooke got his chance at a fire in the Sudbury District. Using a lone Otter equipped with roll tanks, he was able to hold a strip of fire about one mile long until the ground crews could get in and get their firefighting equipment set up. It was later conceded that without the aerial waterbombing, the fire would have quickly grown into unmanageable proportions.
The advent of the more powerful Turbo Beaver aircraft in 1965, led the Air Service back to the idea of taking water directly into the floats. In collaboration with Field Aviation, this original 1944 idea was perfected, and later adapted to all OPAS aircraft. Carl Crossley's dream of aerial firefighting through waterbombing had come full circle.
