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The future of aerial firefighting

By Ben Forrest

Published on: January 16, 2024
Estimated reading time 21 minutes, 36 seconds.

As wildfires grow in number and intensity, aerial firefighting companies are embracing the need to innovate quickly.

On the forest-filled, tinder-dry outskirts of a densely populated California community in the not-too-distant future, flames tear through thickets of trees at an alarming rate. The so-called “Super Bowl of aerial firefighting” is in full swing, and like gritty linebackers defending an end zone, fire crews work quickly and methodically to stop the blaze before it spreads.

Cal Fire and several other firefighting services in California operate Sikorsky FireHawk helicopters, converted from military- surplus Black Hawks by Kawak Aviation. Jeremy Ulloa Photo

Overhead, a trio of Boeing CH-47 Chinook helicopters swoop over the blaze, each dropping thousands of gallons of water, flame retardant, foam or gel. The first aircraft transmits its flow rate and drop pattern through a wide area augmentation system (WAAS)-corrected GPS in a meshed network, passing data to the next helicopter in line, which begins its own water drop with little overlap. The next helicopter in line does the same.

This kind of coordinated aerial fire brigade is a page out of the U.S. Military playbook, mimicking the attack patterns of Boeing AH-64 Apache helicopters on the battlefield. And while it’s not yet a common capability among firefighters in North America, it may be a key part of the industry’s next wave of innovation.

“That’s kind of the mode we’re working on,” said Britton Coulson, president and chief operating officer at Coulson Aviation, the renowned international firefighting company based in Port Alberni, British Columbia. “[We’re] employing new technology, new programming — using military-derived tech to size up the fire, and then be able to allocate a drop to it.”

This military-style evolution is part of an industry-wide response to the growing prevalence and increasing intensity of wildfires around the world. Canada’s disastrous 2023 wildfire season, paired with busy seasons in California and elsewhere, have added urgency to the innovation agendas of aerial firefighting operations that feel the need to consistently raise their game.

“We call it the ‘Super Bowl of firefighting’ because there is no next ridge,” said Coulson, referring to the demanding conditions of southern California. “The ‘next ridge’ is $100 million in homes and a bunch of people. So you have to hit [the fire] as hard and as fast as possible, even if it’s not in the ideal terrain.”

Belly tanks enable operators to quickly drop large quantities of water on wildfires, impeding their ability to spread. Anthony Pecchi Photo

Speed and intensity

In the literal — and figurative — heat of a high-stakes aerial firefighting battle, the speed and intensity of a water drop is one of the most crucial determinants of success.

It’s something Coulson Aviation identified early, as it designed its proprietary 3,000-US gallon (11,300-liter) retardant aerial delivery system – large (RADS-L) tank for CH-47 Chinook firefighting helicopters. Unlike other tanks, it disperses liquid through a large linear hole cut in the floor of the aircraft, making massive drops with a high level of precision, thanks in part to a touchscreen in-cockpit controller that automatically adjusts the flow rate.

Another equally important innovation is the ability to stifle fires with heavy-lift helicopters at night, using crews with night vision goggles (NVGs). Coulson Aviation is the only company in the world with this capability on heavy-lift helicopters, primarily leveraging the Chinook platform.

Firefighting buckets, suspended beneath helicopters as an external load, remain important firefighting tools. Lloyd Horgan Photo

“The program has been extremely successful,” Coulson said. “Anything that we’ve been out at night, we’ve been able to work with the ground crews and catch. Between us and our agency partners, there hasn’t been any fire that’s gone beyond the nighttime that we’ve fought. We see so much success with the larger assets. That’s really where we’re focused, on optimizing those — leveraging the new technology both with our tanking system, as well as NVGs.”

At night, temperatures drop and humidity rises, creating an advantage for firefighters. And since there are fewer aircraft flying after dark, the less-crowded airspace, populated only by specially trained Coulson and agency pilots, is seen as safer for operators.

By operating 24/7, aerial crews are also able to prevent fires from growing back overnight.

Coulson Aviation built its expertise on nighttime firefighting with its fleet of legacy Sikorsky S-76 and S-61 helicopters, the latter of which was for many years the workhorse of its rotorcraft fleet.

Those platforms continue to fly, using NVGs and a high-powered laser pointer to pinpoint the ideal drop zone using an S-76 supervision helicopter equipped with a forward-looking infrared (FLIR) thermal camera.

The S-61s follow closely and douse the flames with 1,000-US gal (3,800-L) Coulson external Fire Boss tanks.

“We still run them,” said Coulson, referring to the S-61s. “They have a great cabin. We have all the STCs [supplemental type certificates] and approvals to do rappel and hoist operations out of them, so they do still have a life out there. But we’re not investing in any different tanks or any major technological advancements in those. We’re really focused on the ‘super-heavies’ … large helitankers and airtankers.”

Rapid-fill snorkels enable CH-47 Chinook helicopters to collect water while hovering over any water source, refilling their tanks in a matter of seconds. Skip Robinson Photo

Another key innovator on firefighting Chinooks includes Kawak Aviation in Bend, Oregon, which makes a 2,500-US gal (9,460-L) internal tank exclusively for Billings Flying Service in Montana. Billings has, in turn, resold several Kawak CH-47 tanks to PJ Helicopters in Red Bluff, California.

The Kawak tank has a 50-horsepower auxiliary hydraulic pump system and a complementary 128-US gal (484-L) foam tank, along with a fixed snorkel that can hover over any water source and refill the tank in 40 seconds with a 4,000-US gal-per-minute (15,100-L-per-minute) fill rate, the company said.

“The beauty of the heavy lift aircraft is that it carries a bigger payload,” said Andrew Mills, vice president of business development at Kawak Aviation. “It’s a fast, reliable, heavy-punch payload helicopter …  the feedback we get from our customers is that they love the tanked Chinook, and the [U.S.] Forest Service loves the tanked Chinook.”

DART Aerospace, headquartered in Montreal, also makes a 3,050-US gal (11,545-L) tank for the CH-47D Chinook that takes about one minute to refill, with rapid roll-on/roll-off installation and removal.

Snorkels making a difference

At a glance, rapid-fill snorkels might seem like small, insignificant features. But in reality, they’re an extremely useful technology that appears to be making a huge impact in the field.

Companies like SEI Industries and Kawak Aviation continue to develop and distribute innovative firefighting buckets for use in increasingly intense wildfire conditions. Lloyd Horgan Photo

Retractable snorkels provide operators with enhanced flexibility in the field, refilling in a matter of seconds without returning to base, and in some cases, making it possible to carry out one drop every 10 minutes on missions that can last more than two hours.

Retractable snorkels also make it possible to hover-taxi at airports when returning to base, Coulson said. This simplifies the process and avoids potential hazards when a fixed snorkel dangles from the aircraft and needs to be captured and guided by ground crews.

An unanticipated benefit of this capability is the retractable snorkels’ performance in cold weather conditions. Coulson cited the company’s experience with aerial firefighting in South Korea, where the fire season carries over into winter.

“Just by the method of rolling it up, it squeegees the water out, so you have way less residual in there,” he said. “The snorkel head also can’t ice up because it’s sitting inside the outer mold line of the helicopter. Cold weather operations are something we hadn’t really identified when we designed [the retractable snorkel], but it’s a night-and-day difference in those type of [operations], compared to fixed snorkels.”

Both Coulson Aviation and Kawak have developed retractable snorkels and belly tanks for Sikorsky S-70i and UH-60 Black Hawk helicopters, which are massively influential among firefighting operations in North America, particularly in California.

Kawak is the sole provider of belly tanks and retractable snorkel systems for the Firehawk iteration of the aircraft, which first entered the market about 20 years ago and has 20 active platforms in California with Cal Fire, the Los Angeles County Fire Department, and fire departments in San Diego, Ventura County and Santa Barbara County.

United Rotorcraft completes installations of Kawak tanks and snorkels, and newer models are fitted with second-generation tanks with better baffles and drop patterns, Mills said. The Firehawk’s retractable snorkel deploys in about five seconds and also does not use the hook cavity, allowing Firehawk operators to use the hook for search-and-rescue and hoist missions.

Coulson Aviation’s internal retardant aerial delivery system – large (RADS-L) tank for CH-47 Chinook helicopters carries up to 3,000-US gallons (11,300-liters). Skip Robinson Photo

“The feedback we get from the agencies that fly the Firehawk is that they love it,” Mills said. “It’s a very maneuverable aircraft, it carries a very good payload, it’s fast, and it’s very reliable.”

As of September 2023, Kawak was in the midst of another multi-aircraft contract for an unspecified customer that would bring the total fleet population up to 24. Deliveries of two systems were imminent for the Orange County fire department, Mills said.

Until recently, Coulson was working on a RADS-M (medium) tank for its three Black Hawk helicopters — essentially a smaller version of its Chinook tank with similar capabilities — but has shelved that project temporarily as it waits for more favorable market conditions.

“I think the Black Hawk’s a great aircraft,” Coulson said. “It’s very reliable, the pilots love it, maintenance loves it. The contracts just need to be more viable to be able to get back into that again.”

DART Aerospace also developed a Blackhawk Fire Attack System, with a 900-US gal (3,400-L) internal roll-on/roll-off tank that can be removed or installed in 15 minutes and has a fill time of less than one minute, the company said.

The tank is certified by the U.S. Federal Aviation Administration (FAA) for day or night visual flight rules (VFR) missions and has a hover refill pump with dual ground fill ports, an available crew chief cabin for transporting firefighters, and an independent foam system.

Orange County Fire Authority utilized CH-47F Chinook helicopters from Coulson Aviation, similar to this one, in 2023, as part of southern California’s Quick Reaction Force. Los Angeles and Ventura county fire departments also partnered in the program. Skip Robinson Photo

Torches and buckets

In June 2023, the British Columbia Wildfire Service released a YouTube video of a Bell 429 helicopter dropping burning gelled gasoline onto a swath of coniferous trees. The video went viral, prompting media explainers and drawing public attention to another long-held aerial firefighting technique that has recently been updated by enterprising engineers.

For several years, B.C. has leveraged the helitorch, a large external drum of gelled gasoline suspended under the helicopter to create prescribed burns, as a proactive wildfire containment tool.

A new-generation version helitorch was designed and built in 2019 by the U.S. Department of Agriculture Forest Service, through the National Technology and Development Program, for use in the U.S. The system uses a propane flame, created by an electric spark, to ignite gelled fuel that flows out of a 55-US gal (208-L) fuel drum and through a fuel transfer pump.

This new version is designed for “simple and reliable operation,” with parts that are readily accessible for inspection, repair, replacement and cleaning. The controls are similar to previous-generation torches, making the transition between models easy, the Forest Service said.

Meanwhile, SEI Industries in Delta, B.C., developed another helicopter-mounted device for controlled burns called the Red Dragon. It dispenses large quantities of “aerial spheres” called Dragon Eggs, injected with flammable ethylene glycol. The system was patented in the U.S. in 2014 and uses a quick-purge dispenser system controlled with a hand-held remote.

The company’s Sling Dragon aerial ignition system resembles a helitorch in some ways, dispensing one-inch Dragon Eggs from a hopper slung beneath a helicopter, delivering up to 225 projectiles per minute and utilizing available GPS tracking.

At the same time, firefighting buckets remain a key tool for aerial crews around the world. SEI Industries and its Bambi Bucket systems have been in use for decades, with multiple models and quick-fill functionality.

In 2023, Kawak Aviation introduced its new Cascade collapsible water bucket, with a 900-US gal (3,400-L) capacity and 1,600-US gal-per-minute (6,000-L-per-minute) fill rate via a high-powered pump. The Cascade is lighter than competing buckets but also reliable and scalable for different needs, the company said.

“We will expand it to other sizes, but it’s kind of unique in that it’s more of a vertical bucket in shape, and it has a very rugged, robust, stainless steel frame at the bottom,” Mills said. “So when you drop it into the water, it sinks immediately, straight down, which makes it fill faster … it’s one more tool in the arsenal for firefighters. We’ve sold several of them already, and we expect to be producing those in higher quantities in the next year.”

Erickson Air-Crane helicopters have been valued aerial firefighting platforms for many years, but innovation with other heavy-lift platforms — including Sikorsky UH-60 Black Hawks and Boeing CH-47 Chinooks — have also proved to be powerful weapons in the fight against wildfires. John Pitsakis Photo

Future innovation 

As wildfires continue to grow in number, size and intensity, aerial firefighting companies know they need to adapt quickly. Continued innovation is a non-negotiable requirement, and the industry has embraced that principle.

New products are being developed, often in secret, and existing products are being fine-tuned in response to changing conditions in the real world.

“I think there will continue to be increased demand for firefighting helicopters,” Mills said. “That means they need more aircraft, and those aircraft are going to require rugged, reliable aerial dispersal systems — tanks and buckets. There’s a place for both … we do see a requirement for continued innovation.”

At Coulson Aviation, military-style technology — including meshed networks that share in-flight data between helicopters to blanket a fire more effectively with multiple aircraft — is front-of-mind.

“I think firefighting can get there,” said Coulson, referring to military-style attack patterns, inspired by the AH-64 Apache. “That’s really where our main focus is on the rotary-wing side right now.”

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1 Comment

  1. Thanks for this great overview – how far away are we from analysing drop patterns in situ as you mention in the beginning of the article? For now, the number of scientific publications is fairly low, we’d love to see whether there is potential to study these in more detail.

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