Firefighting by air— challenge and triumph
Niche activity uses everything from helicopters, warbirds and airliners to purpose-built airtankers.
Unlike converted airframes, the Bombardier CL415 “Superscooper” is the only purpose-built turboprop firefighting aircraft. More than 75 have been built, and are in service in many countries around the world.
Aerial firefighting would grow to encompass perhaps the most diverse assortment of large ex-military aircraft in operation, and eventually give rise to a purpose-built airtanker.
CDF, a leader by necessity, given the frequency of wildfires in its state, initially acquired a varied fleet of WWII veteran aircraft, including 14 Grumman TBM Avengers, 5 Grumman F7F Tigercats, a Consolidated PBY Catalina and a Boeing B17 Fortress.
Private firms followed suit, and soon Douglas DC4s, DC6s, DC7s, Consolidated PBY4s, Boeing C97s and Fairchild C119s could be seen in active service once more—this time as airtankers. Due to a dwindling parts supply for its more vintage types, CDF eventually chose the smaller Grumman S2A Tracker—an ex-US Navy sub-hunter.
By 1990, Lockheed C130As, having already passed through the hands of several owners after the US military, were drafted into aerial firefighting by Hawkins & Powers and TBM Inc. Further north, in Canada, a truly gigantic aircraft was resurrected into the role of aerial firefighter—the Martin JRM1 Mars flying boat.
An anachronism from the closing days of WWII, the design suffered the fate of other large transport aircraft of its day. Built too late to be of significance to the war effort, the first JRM1 wasn’t delivered to the US Navy until Jun 1945. By August the war was over, and the order for 20 was scaled back to the 5 already on the production line.
One was lost to an engine fire while still with the Navy, and in 1959 the remaining 4 were purchased and converted to airtankers by Flying Tankers Inc. Today, 2 survive in the airtanker role, owned and operated by Coulson Flying Tankers of Canada.
Beriev’s BE200 Altair, one of a handful of the type operated by Russia’s Emergency Control Ministry, is the only turbojet-powered amphibious airtanker in use. It holds more than 3000 gal of water for firefighting.
Through the American Incident Command System (AICS), the varied fleet of airtankers was categorized into 4 subcategories, effectively by volume of extinguishing material held. The largest tankers are categorized as Type I—defined as an airtanker holding greater than 3000 gal of retardant or water.
Type I airtankers include Lockheed stablemates such as the P3 Orion and the C130 Hercules. For comparison, the Martin Mars holds over 7200 gal. Yet, compared to the largest airtankers now in service, even the mighty Mars’ capacity seems but a drop in the bucket.
Type II covers airtankers with a capacity of 1800–3000 gal. Neptune Aviation’s Lockheed P2V Neptunes are an example of Type II airtankers. Previously, the C119 and B17 ruled this category. In the wake of the 2002 crashes, all Type I and II airtankers were grounded, leaving small and medium airtankers and helicopters to continue the fight while the industry reinvented itself.
By summer 2004, the Type III airtanker—one with 600–1799 gal capacity—had big shoes to fill. As popularized in the 1989 movie “Always,” the Douglas A26 Invader and PBY Catalina once filled this role, but in the US today, perhaps the most prolific example of a medium airtanker in terms of sheer numbers is CDF’s fleet of S2As and S2Ts.
By 1972, CDF had already acquired some 19 S2As and in 2003, 15 S2Ts began replacing the radial-powered S2As. Another Type III tanker is the only Western purpose-built airtanker in history—the radial-powered Bombardier CL215 and the later turboprop-powered CL415.
Unique in form and function, the CL415 “Superscooper” is an amphibian, able to fill its 1621-gal-capacity hold in 12 sec. Four CL415s serve in the US, while the remaining 70-some aircraft operate internationally, the majority of them in Canada.
Evergreen Aviation’s 747 Supertanker can dispense 20,000 gal of water or retardant and is currently the largest airtanker in use.
Smallest of all, Type IV airtankers hold 100–599 gallons of retardant or water. As one might expect, these are largely ex-agricultural spraying aircraft, often referred to as single-engine airtankers (SEATs). Many SEAT aircraft are built by Air Tractor, which produces a varied line of aircraft from the agricultural AT401B to the AT802 Fireboss.
The first Stearman airtanker would have qualified in this category. While airtankers tend to be emblematic of aerial firefighting, the rotary-wing side is just as important. Smaller command helicopters as well as Bambi Bucket wielding heavylift helicopters play a key role in the carefully coordinated aerial attack profiles of firefighting.
Though many larger helicopters use the Bambi Bucket to great effect, one helitanker in particular—the Erickson S64 Skycrane—is also equipped with a ram scoop hydrofoil which is deployed while the Skycrane skims along the water’s surface, filling the Skycrane’s 2650-gal tank in as little as 45 sec.
Other notable heavylifters include the Boeing Vertol BV234, operated by Columbia Helicopters and capable of lifting 28,000 lbs at sea level. It carries a 2650-gal SEI Torrentula Bambi Bucket which can be filled in less than 2 minutes. Notable in this system is that the bucket is suspended some 200 ft below the helicopter, allowing it to use smaller water sources that might otherwise be inaccessible.
Future aerial firefighting aircraft
In the years since the grounding of Type I and II airtankers, the industry has undertaken changes that demonstrate that the losses of personnel and aircraft were not in vain. Today’s more notable large airtankers include 10 Tanker Air Carrier’s 2 converted Douglas DC10s and Evergreen’s Boeing 747-200 Supertanker, both developed largely in response to the continued need for very large airtankers.
The aircraft can dispense 12,000 and 20,000 gal of retardant, respectively. By comparison, CDF’s venerable S2T would require more than 15 drops of its 1200-gal load to match Evergreen’s Supertanker. Another airliner-cum-tanker is Cascade Aerospace’s conversion of the Bombardier Dash 8-400.