In the summer in the United States, forest fires are always a big problem, especially in the states of California and Alaska. Thousands of hectares of land and forest are decimated by fire every year, in addition to the loss of human and animal lives and the destruction of cars, homes and other properties.
According to the Congressional Research Service, in 2022 alone, 68,9 forest fires were recorded, destroying 3,07 million hectares.
The US has been using aircraft to fight forest fires for decades, from small helicopters that transport firefighters and firefighters to the fire line to large commercial jets, such as the DC-10 and the Boeing 747-400 Supertanker. There are several models, but today we are going to talk specifically about a rotary-wing aircraft: the S-70 Firehawk.
History
The Sikorsky S-70 Firehawk is one of several variants of the UH-60 Black Hawk, a model developed by Sikorsky (a company that is now part of Lockheed Martin) to replace the US Army's classic UH-1 Huey. The Black Hawk has been present in countless military operations around the world, proving its value and showing its capabilities in troop insertion and extraction, aeromedical evacuations, supply transport, search and rescue and several other missions.
In Brazil, the Black Hawk is in service in Brazilian air force and in the Brazilian Army, while the Brazilian Navy employs the S-70B Seahawk in rescue, patrol and anti-submarine/anti-surface warfare missions.
In the late 1990s, the Los Angeles County Fire Department (LACoFD) teamed up with Sikorsky and United Rotorcraft to develop a version of the Black Hawk with firefighting capabilities. Thus, three S-70A Black Hawks acquired by firefighters were modified by United to perform this noble mission.
The modifications
It is important to highlight that the Black Hawk could already be used as a firefighting platform, but for this it used a tool called Bambi Bucket. Created by Canadian Don Arney, the bambi bucket is one of the most used instruments in forest fires. Basically it is a basket carried by the hook of the helicopter fuselage with an opening at the bottom, operated mechanically.
The basket is filled with water when immersed in a lake, sea, river or even a swimming pool (which occurs quite commonly). The helicopter flies to the fire, dumps the water and the operation is repeated multiple times. Despite its versatility, the bambi bucket doesn't carry as much water. Another limitation is the use of retardant chemicals, which would need to be replenished along with the water.
United Rotorcraft carried out, together with Lockheed, the development of a package of modifications that would transform the Black Hawk into the Firehawk, a true Black Hawk for firefighters. There are two main modifications: a ventral water tank and the extension of the front landing gear.
The Firehawk has a tank capable of transporting and launching 3785 liters of water, Ou seja, 1287 liters more than the maximum capacity of the largest Bambi Bucket employed by the Black Hawk.
Integrated into the main tank, the Firehawk has a smaller fuel tank. 114 liters for the mixture of retardant chemicals, a product widely used in fighting forest fires and recognized by its red color. The tank also has an internal spray for cleaning and the V-shaped doors allow water to be poured with force and precision, through leaves, branches and bushes to reach the flames.
To receive the tank in the belly, the S-70's front landing gear was extended by 45,7 centimeters. Larger steps were installed for boarding and disembarking firefighters and crew.
The Firehawk can refill its tank in two ways. One is by landing the aircraft and filling it with water through an opening, which can be done with a fire engine, for example. However, the main way is to use the integrated retractable snorkel.
The equipment is a 3,6 meter rigid hose, mounted on the right side of the tank. When the tank needs to be refilled, the pilot takes the helicopter to a water source, activates the control that extends the hose and a pump begins suction.
Early versions of the Firehawk had a pump with enough power to complete refueling in 1 minute. The newer S-70i received a bomb capable of refilling the tank in just 45 seconds. With the tank full, the hose is collected and the helicopter leaves for the fire.
Pump power comes from two General Electric T700-GE-401D turboshaft engines, each capable of generating a maximum continuous power of 3356 shp.
“These machines are experiencing some of the most extreme conditions you can imagine in a helicopter. Every time the aircraft is fighting a fire, it reaches full power six to eight times an hour. It must handle the heat, but also the heavy lifting when the tank is full of water.”, said Bill Neth, customer program manager for GE Aviation.
It is precisely the military design of the Black Hawk that allows the Firehawk to withstand the demands of firefighting flight. The helicopter is capable of making 4G turns with a completely full tank, flying through dense and hot smoke.
With from UH-60 operations in the Middle East, GE improved the T700's performance in high-temperature conditions, while Sikorsky made improvements to the main rotor blades. Customer options include a filter in the air intakes and folding blades for transport.
In addition to firefighting
The main function of the Firehawk is to fight flames in forest fires, but the aircraft's working method will depend on who is the operator. As the Firehawk's first customer, the Los Angeles firefighters have developed, over the years of operation, the most diverse techniques for using the Black Hawk.
The Firehawk is also responsible for transporting forest firefighters to the battle line. The aircraft is capable of transporting 11 to 13 fully equipped firefighters (according to the cabin configuration) leaving them at the designated location, refueling their tank and returning to the fire area.
This type of operation is carried out in the first stages of a vegetation fire, a phase considered critical for fighting as the fire is weaker. The S-268's maximum speed of 70 km/h, combined with advanced firefighter bases, allows rapid movement to the fire source.
In addition, the Firehawk also has an external side winch for search and rescue missions. If the ventral tank is removed, the aircraft can make use of the hook in the center of the fuselage, capable of carrying objects of up to 4 tons. On medevac missions, the cabin can be configured to carry up to four patients on stretchers.
For precision hovering, the Firehawk features a four-axis digital autopilot, certified for single-pilot operations. The fully digitalized cabin reduces pilots' workload and streamlines the multiple operations that the aircraft can perform.
Pilots can also wear night vision goggles and the helicopter can be fitted with an infrared sensor (FLIR) or search beacon.
s and versions
As previously mentioned, the launch customer for the S-70 Firehawk was LACoFD, with three S-70As in the late 1990s/early 2000s. Today the institution has two more S-70i, the newest version of the Firehawk, with a total fleet of five aircraft. The helicopters are manufactured in Poland by PZL-Mielec, a subsidiary of Lockheed, and taken to United Rotorcraft, in the state of Colorado, where they are modified for fire services.
The S-70i also features a digital glass cockpit, automated flight control system, active vibration control and vehicle health monitoring system. As an option, Sikorsky offers ADS-B, mission planning system, moving map, weather radar and other items.
The California Department of Forestry and Fire Protection (CAL FIRE) has three S-70i and has ordered a total of 12 aircraft, the largest order to date. The San Diego Fire Department (SDFD), also in California, has only one S-70i.
Jared Polis, Governor of Colorado, has proposed purchasing a Firehawk for the 2021-2022 fiscal budget as well as purchasing more units of the model later this decade. The aircraft would be operated by the Colorado Air Corps, a state that also suffers during wildfire seasons. United said several other states in the western US have shown interest in the model.
Since it began operating in Los Angeles County, the Firehawk has demonstrated agility, reliability and robustness in firefighting operations. Even though it is an expensive asset, with the price varying between US$ 19 million and US$ 22 million according to the order, the aircraft is a strategic weapon against the fires that devastate the region annually.
“For the money of a helicopter, they could buy 50 or 60 vehicles, open stations, but the impact of the Firehawk is incredible”, said Mike Sagely, LACoFD Air Operations senior pilot, in a report by Helicopter Magazine.
Curiosity
The famous game Grand Theft Auto: San Andreas, or just GTA, was part (or still is) part of the lives of many of our readers, including this editor. But what does this have to do with the S-70? Well, he was in the game in a way.
Producer Rockstar inserted the helicopter into the game in the form of Raindance. The model did not have the ventral tank, nor the side winch, but sported a painting similar to that of the prototype Firehawk. In the game, the 'S-70 Raindance' was found in San Fierro and on Santa Maria Beach, locations that simulated the cities of San Francisco and Los Angeles.
