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MOVING WATER RESEARCH INFORMS AIRTANKER PROGRAM

BY COLIN MCFAYDEN AND JASON ROBINSON

Managing wildland fire in Canada is a large and growing challenge. In Canada’s vast boreal forest, fire – high intensity crown fire – is a natural part of the ecosystem, quickly burning large tracks of land in spectacular fashion, often regenerating unhealthy forest. Across Canada, lightning starts thousands of fires each year, and those fires constitute most of the area burned. But as in many other regions, there is a requirement to balance the need for fire’s natural role with the critical need to protect people, property, and resources from fire’s unwanted consequences.

In many instances, it’s a priority for fire managers to suppress and control wildland fires, preferably when the fires are small. There are many situations where conventional ground suppression tactics (firefighters with pumps and hose) cannot succeed alone and must be supported by aerial suppression resources. In many cases, fixed wing airtankers are the first and sometimes last line of defence in these extreme fires.

There are several variations of fixed and rotary wing airtankers available to fire managers across Canada, such as ground-loaded chemical retardant tankers, skimmer airtankers (commonly known as waterbombers) and helicopters equipped with buckets or tank systems. In eastern Canada, an abundance of lakes makes waterbombers the preferred option as they are favoured for their quick turnaround time and operational flexibility. Waterbombers skim the water’s surface to pick up and then drop water onto the fire’s edge to reduce fire intensity and slow fire progression so ground crews can safely and effectively work the edge.

There are situations where the available resources simply cannot deliver enough water to successfully address every threat, for example, the 2018 fire season in eastern Ontario. On a single day in July, a high-intensity fire made a run toward a community and all nine of the province’s heavy CL-415 airtankers worked that fire at the same time, dropping more than two million litres of water (~77,000 cubic feet). That fire was not declared under control for 10 more days and was not extinguished for another month. That fire was just one of at least 90 fires burning in Ontario that day. While the decision to redirect the entire fleet of heavy waterbombers to this one fire seemed to pay off, it was not without risk, as it significantly limited the ability to respond to any new fires or to support existing fires.

A CL-415 knocking down an intense portion of a fire in northern Ontario. Photos courtesy of Ontario Ministry of Natural Resources and Forestry.
A CL-415 knocking down an intense portion of a fire in northern Ontario. Photos courtesy of Ontario Ministry of Natural Resources and Forestry.

It’s very rare for all of Ontario’s heavy waterbombers to be used on a single fire. Waterbombers are normally widely dispersed, following the fire hazard, across Ontario’s 107 million hectares. This approach of distributing waterbombers enables fire managers to support initial attack over broad geographic areas. However, as the wildland fire environment changes, there have been more cases of these hard-to-fight and threatening fires requiring more airtanker support. Analysis suggests that these situations will increase in frequency, and far more air and ground resources will be needed to maintain the current level of protection.

More recently, Ontario began to supplement its airtanker capacity with contracted belly tanked helicopters for lower-intensity fires that do not need the full punch of the heavy waterbombers. The different aircraft provide more options with varying operating costs, safety considerations, and training requirements. The additional capacity however also comes with new challenges for daily decision making, namely, where to deploy the mix of airtankers, and which type of airtanker to dispatch.

A CL-415 dropping along the fires edge, ensuring safe conditions for incoming Fire Rangers.
A CL-415 dropping along the fires edge, ensuring safe conditions for incoming Fire Rangers.

In 2017, the Canadian Forest Service and Ontario’s Ministry of Natural Resources and Forestry began collaborating to develop new methodologies to inform and support fire managers challenged with these decision-making problems. This isn’t uncharted territory; work on airtanker effectiveness in Canada dates back at least to the early 1960s, not long after the idea of waterbombing first took hold (also in Ontario around 1944). This current research is focusing on the first principles needed to understand and compare airtanker effectiveness – the size and concentration of a drop and what that drop will mean in context of the change in fire behaviour. The research included a novel means to measure water drop patterns at high spatial resolution using infrared scanning technology. One of the early results of this research program will be the publication of the Reference Guide to the Drop Effectiveness of Skimmer and Rotary Wing Airtankers. This guide is intended to provide a systematic and objective method for the relative comparison of the water drop effectiveness of both fixed- and rotary-wing airtankers commonly used in the North American boreal regions.

This recent work only skims the surface of the information needed to support the challenging strategic and tactical questions facing airtanker operations as the wildland fire environment and wildland fire management become increasingly challenging.

ABOUT THE AUTHORS

Colin McFayden is the Forest Fire Research Knowledge Exchange Program lead for the Great Lakes Forestry Center of the Canadian Forest Service (CFS). McFayden spent the last few decades with the Ontario government working his way up from the field as a fire ranger, to leading the wildland fire science program. With a recent move the CFS in 2022, McFayden’s current focus is to support Canada’s WildFireSat mission as lead of the knowledge exchange program for operational implementation (WildFireSat is the world’s first purpose-built operational satellite system for monitoring wildfires). From space to the forest floor, all aspects of the interaction of science and fire management are of keen interest.

Jason Robinson is the aerial fire operations co-ordinator for the Ontario Ministry of Natural Resources and Forestry, Aviation and Forest Fire Emergency Services. Originally from the northern town of Red Rock, Ontario, Robinson has spent the last three decades protecting the people of Ontario from wildland fire. Robinson is a nationally certified air attack officer with more than 500 fires under his belt before he moved into a leadership role overseeing Ontario’s Aerial Fire Operations Unit. Robinson is committed to seeking ways to improve safety, effectiveness, and efficiencies in aerial fire operations in Canada and with its partners. This work is his passion, and he is a tireless advocate for innovation.