As wildfires increasingly rage across the US, first responders are relying more and more on aircraft for firefighting operations. Given that helicopters can operate in a variety of weather conditions and at varying altitudes, they allow crews to access fires more closely and precisely.
Aircraft manufacturers, researchers, and first responders say wildfires are most efficiently extinguished with 1,000-gallon tanks along with drones that gather data on fire characteristics, therefore, designers have continued to develop and upgrade existing airframes that work more quickly between lifts and drops.
In 2018, the US Forest Service is expected to utilize nearly 200 helicopters, said Jennifer Jones, a spokesperson with the Forest Service and Fire and National Interagency Fire Center. The service’s firefighting fleet includes 28 heavy, 34 medium and 43 light helicopters, which are contracted exclusively through companies like FairLifts.
“Different types of fixed-wing aircraft and helicopters play different roles in wildfire suppression, and both are important,” Jones said. “The Forest Service strives to maintain the appropriate mix of aerial firefighting aircraft within available funding.”
Jones said the Forest Service will request information regarding next-generation larger helicopters, aircraft that can carry 1,000 gallons or more.
The Forest Service and other agencies respond annually to more than 73,000 wildfires, which burned roughly 7 million acres and more than 2,600 structures. A recent upgrade to existing airframes has been the addition of interior tanks, which lower fuel consumption.
Sikorsky’s modified Firehawk, a third-generation Black Hawk, features a snorkel and 1,000-gallon tank. The aircraft’s extended landing gear elevates the helicopter in order to attach tank with belly mounts. Storage drawers allow a variety of drop patterns for extended coverage or larger water release.
“Without this type of aircraft, we can’t drop the volume of water that allows us to get that early attack on a fire,” said Los Angeles County Fire Department Battalion Chief Pat Sprengel. In 2017, 9,000 wildfires consumed 1.2 million acres in California, and Los Angeles County crews used Firehawks in day and night operations.
“Firehawk’s biggest technology gain is demonstrated through the increase in performance, especially at higher altitudes and temperatures, and the ability to carry more payload or more water and fuel during firefighting,” said Jeanette Eaton, Sikorsky’s regional sales executive for the U.S. and Canada. “The increased performance margin also amplifies safety. Precision-hover capability using enhanced GPS and inertial navigation systems, combined with hover position micro adjustments (the ability to input micro adjustments left, right, front or back) with a cyclic trim beeper is new to the -60M/S-70 and will be useful in hoist operations, even in crosswinds at higher altitudes.”
Also, the wide-chord rotor blades increase stall speed on the blade, which increases speed (12 kt improvement in optimal range speed). The S-70i features a reinforced airframe, digital cockpit and flight management system.
“To justify budgets and provide citizens the best use of taxpayers’ dollars, our customers require a proven, effective, multi-mission aircraft,” Eaton said.
Richard Buchanan, Honeywell’s senior director of commercial helicopter business, said the new HTS900 engine in the retrofitted Bell Eagle 407HP consumes less gas than its older engine, enabling more turnarounds. Bell currently has 120 rotorcraft in North America, said Anthony Moreland, the company’s managing director of the region, and anticipates its 525 Relentless fly-by-wire model, which is currently being tested, will allow first responders to carry up to 28,000 pounds in resources.
Having rotorcraft operate at night is a priority for helicopter manufacturers and states. California is the first state to fight fires at night with rotorcraft.
Ben Miller, director of the Center of Excellence for Advanced Technology for Aerial Firefighting within Colorado’s Division of Fire Prevention and Control, said he hoping to improve aerial situational awareness during nighttime operations in Colorado’s higher altitudes. The center is testing technologies for initial attacks and night operations, as well as for natural and urban environments.
“We’re starting with rotorcraft suppression techniques,” Miller said. “There are safety implications posed by weight increments with both tanks and buckets. We’re understanding what’s best for each given fire – and looking at how they collect it, land at the base and pump on board or dip a bucket.”
“We use aircraft measurements to conduct simulations of fires for predictions,” said Barbara Brown, a scientist with the National Center for Atmospheric Research in Colorado. “We are using drones to gather data on fire perimeters – and a weather and fire model to predict how fires spread. We are also looking at the impact of fuel moisture on fires and its impact on the size and spread patterns of fires, and how its use and impact has changed over time.”