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Yukon Yellow Birds page 2

Story by Robert S. Grant • PHOTOS BY JASON FRIESEN

Canada has nearly 50 Canadair CL-215s and CL-415s stationed across the country through government and commercial agencies. During dry seasons, provinces agree to share resources. Fire headquarters contact the CIFFC to request additional equipment or personnel. In this case, Ontario’s four CL‑215s became available, but the crews of five recently acquired turbine-powered CL-415s were still undergoing familiarization with the new type.

First flown in October 1967, the amphibious CL-215 stood out as the first airplane designed primarily for fire suppression. Exceptionally effective compared to predecessor Consolidated Cansos, it soon became the primary line of defence against the dreaded natural holocausts that ravage Canadian forests every spring and summer. Powered by 18-cylinder Pratt & Whitney 2100-hp R-2800s, the 43,500-pound gross weight flying fire truck scoops 1,200 Imperial gallons in 12 to 14 seconds. The load is discharged through two 63 x 32-inch doors 120 to 130 feet above ground at optimum speeds of 110 knots. Experts consider drop height to be a key factor in generating good-quality foam from the onboard injection systems.

The CL-215’s raison d’être centres on a pair of water tanks located inside the cabin and beneath the wings. The lower two-thirds lie below floor level and form part of the hull while a fibreglass section makes up the remainder visible from behind the panoramic cockpit. Two large additional internal containers inside the fuselage hold nearly 1,600 pounds of clear, soap-like foam.

The OMNR’s first CL-215 came on line in 1983, and eventually nine carried the all-yellow with black or red speed lines until CL-415s entered service in early 1998. Both types carry enough fuel to work a fire for four hours and return to base on reserves. Yukon firefighting veterans request a mix of water bombers and airport-only retardant tankers whenever possible. “I can assure you that I always prefer mixed tanker types when initially attacking an aggressive wildfire that is spreading rapidly and spotting,” says Yukon bird dog officer Ben Moerkoert. “This type of scenario really takes advantage of each tanker type’s unique capabilities.”

After arriving in Whitehorse (population 24,000), Ontario pilots noticed considerable differences from working above relatively level boreal forests or Hudson Bay lowlands. Steep-sided Yukon valleys ensured that full takeoff power remained on longer than usual. Higher altitudes and the scarcity of lakes provide little safety margin in case of engine failure. “Blown jugs” or cylinder failures occur with alarming regularity as hours build on the ageing engines.

Also, Ontario’s CL-215s require paved runways at least 5,000 feet for normal takeoffs. Gravel of any kind quickly wears tires, especially during taxi turns. In the Yukon, only two airports have hard surfaces. Although CL‑215s may be amphibious, they rarely stop completely on water. The impracticality of maintaining and feeding a pair of oil-guzzling engines forces operators to station only at airports.

Although Ontario pilots had logged thousands of hours bush flying and understood how to interpret weather and winds in low country, only one had extensive mountain flying experience. Exceptionally rapid velocities of air mass movement required considerable manhandling of the water bomber’s non-boosted flight controls. Slightly south of the fire near Haines Junction, effects from the nearby Kaskawulsh and Lowell Glaciers produced shearing, turbulent conditions. “Katabatic winds can develop to hazardous proportions if the cooling is extreme,” explains a Canadian Forces weather manual. “This can occur over glaciers where shallow winds of 80 knots or more can form.”

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