This Year's Model
Wildland engines come in different configurations for different applications. The specific design is often determined by the fuel load and terrain of a given area, the method of attack employed by the fire department and the number of personnel available for each engine.
Federal and state wildland agencies have been fighting fires for 100 years or more and have developed engines that best meet their needs in certain areas. Many of these designs are widely copied by other departments.
WIDE RANGE
Here is a summary of some of the most common federal and state wildland engines, with an emphasis on their unique features.
The U.S. Department of Agriculture's Forest Service protects 191 million acres of national forests and grasslands throughout the country. Within this area, fire remains the most serious threat. There are nine USFS regions, and each specifies wildland engines to meet its specific needs.
The low-profile USFS Model 33U engine is widely used in Oregon and Washington for initial attack and patrol. Built on a light-duty 4×4 chassis with a two-door cab, the unit has a polypropylene tank that carries 300 gallons of water and 15 gallons of foam. The four-stage pump is driven by an auxiliary engine and delivers 85gpm at 150psi or 14gpm at 400psi. A fully compartmented aluminum body rounds out the package.
With no frills but a thoroughly practical design, the Model 52 is in service with USFS units throughout Montana, Idaho, Nevada, Utah and parts of Wyoming and North Dakota. It is built on a light- or medium-duty 4×4 flatbed truck with two-door or four-door cabs. One version has a 200-gallon or 300-gallon tank, another version has a 700-gallon tank, and all tanks are made of either fiberglass or polypropylene. The auxiliary engine — driven, four-stage pump is rated 85gpm at 150psi or 14gpm at 400psi. A skid-mounted design allows the entire firefighting package to be unbolted and installed on a new chassis. This model is also widely used by the Bureau of Indian Affairs.
The Model 62 is the mainstay of the USFS fleet in California and is used in a variety of wildland fire situations. It is built on a medium-duty chassis with a four-door cab and a choice of either 4×2 or 4×4 drive. A PTO-driven two-stage pump delivers 500gpm at 150psi for high-volume attack or 80gpm at 600psi for long hoselays up steep slopes. The 500-gallon water tank is polypropylene, and a 40-gallon foam cell is provided. Mounting the pump panel at the rear of the body keeps the operator out of traffic and provides clear visibility of the fire scene along both sides of the apparatus for improved safety.
The U.S. Department of the Interior's Bureau of Land Management protects some of the most remote areas in the country. BLM was a pioneer in the use of compressed-air foam for wildland fire suppression, and many of their apparatus are specified with CAFS.
The BLM uses Model 662 throughout the West for initial attack; it's also used by several other federal and state wildland agencies. Built on a light-duty 4×4 chassis with two-door and four-door cab options, the standard configuration uses an auxiliary diesel engine to drive the pump, which is rated 100gpm at 150psi or 35gpm at 400psi. Higher-volume pumps are available in other configurations. A 300-gallon water tank with a 15-gallon to 25-gallon foam cell is standard, and CAFS is optional. The body is made of a fiber-reinforced composite material.
BLM designed the larger Model 667, which is built on a medium-duty 4×4 chassis with either a two-door or four-door cab, for off-road firefighting in the western United States. Rated 140gpm at 150psi or 15gpm at 400psi, the auxiliary diesel engine — driven pump can deliver its full rating at elevations up to 5,000 feet and temperatures up to 100°F. This model can be equipped with either a 500-gallon tank or an 865-gallon tank for extended operations. A foam proportioning system with a 25-gallon foam cell is standard, and CAFS is optional. The tank is polypropylene and the body is stainless steel. Variations of this design are used by several other government wildland agencies.
The California Department of Forestry and Fire Protection is the largest state fire agency in the United States, operating more than 1,000 engines out of 800 stations with a staff that peaks at over 5,000 during wildland fire season. In a typical year, CDF responds to 6,300 wildland fire calls.
Used in almost every part of California, the popular CDF Model 14 wildland engine is built on a medium-duty 4×4 chassis with a four-door cab. The two-stage pump is driven hydraulically from a front engine PTO and is rated 500gpm at 150psi or 80gpm at 600psi. The hydraulic circuit includes a compensator to keep the pump pressure constant as the engine speed varies during pump-and-roll operations. The 500-gallon water tank is integral to the body to reduce weight, and a 20-gallon foam cell is provided. The CDF Model 15 wildland engine is similar, but it has a 4×2 drive. Variations of these two models are used for wildland fire suppression by many other federal and state agencies throughout the United States.
The Florida Division of Forestry is responsible for suppressing wildfires throughout the state with a fleet of wheeled vehicles, tracked vehicles and aircraft depending on the terrain and vegetation. Unlike most other states, Florida's wildfire season starts in December and extends through June.
Their basic initial attack wildland engine is built in the forestry shops on a light-duty 4×4 flatbed truck with a two-door cab. An auxiliary engine-driven pump produces 100gpm at 150psi or 25gpm at 300psi. The polypropylene tank holds 500 gallons of water and has an integral 10-gallon foam cell. The body is built from lightweight aluminum to compensate for the additional weight of water.
The Michigan Department of Natural Resources converts a variety of military and civilian vehicles into wildland fire apparatus at their equipment center in Roscommon. (See sidebar, opposite.) The center also provides wildland engine design, development and testing services to many other state forestry departments.
Built on a used military chassis with a low-profile 900-gallon water tank, Michigan's 2H-ton 6×6 model is widely used as a heavy attack engine. An auxiliary engine drives the four-stage pump, which is rated 85gpm at 150psi or 14gpm at 400psi. A foam proportioner with a 5-gallon foam tank is standard. Cab-operated spray nozzles and hydraulically operated plow units are options. Their 5-ton 6×6 model carries 1,400 gallons of water.
The Nevada Division of Forestry faces a variety of wildland fire hazards and uses a variety of engines to meet them. In most areas, water is scarce, so engines have larger water tanks.
Their Type II 500gpm model is built on a medium-duty 4×4 chassis with a two-door cab. The pump is driven by a crossmount auxiliary diesel engine and produces 500gpm at 150psi or 250gpm at 250psi. The polypropylene tank carries 600 gallons of water, and the body has a large hosebed, enclosed ladder storage and dual hose reels. This model has all the features of a wildland heavy attack engine, plus an upgraded complement of hose and ladders that allows it to provide structure protection as well.
The New Jersey Forest Fire Service operates a fleet that includes wildland engines, tankers, dozer plows, specialized equipment and aircraft. They protect the state's vast forested areas, where the only roads are often not much more than parallel tracks in the sandy soil.
Their standard initial attack engine is built in their own shop using a light-duty 4×4 chassis with a two-door cab and a utility body. The shop installs the pump, tank and plumbing, and finishes by reinforcing the truck on all sides and underneath to provide protection from trees, brush and rocks. The auxiliary engine — driven pump produces 60gpm at 150psi, and the aluminum tank holds 250 gallons of water. This model is used to make aggressive off-road attacks directly through vegetation to reach the fire quickly.
WHAT DOES IT MEAN TO YOU?
Wildland engines used by federal and state agencies tend to have similar pump sizes, tank capacities, foam systems, body materials and overall configuration. These engines provide good service in the areas where they are used, and you may want to adopt some of their specifications for your own wildland engines.
Here are a few points to consider:
- Match the pump to the fuel load
If you specify a pump that is too small, the fire will run away from you; too large and you'll waste water. Select a flow rate that is appropriate for the fuel load in your area. In the examples above, flow rates of 60- to 100gpm at 150psi are common. Multi-stage pumps provide higher pressures for long hoselays up steep slopes. Wildland engines that also are used for structure protection may have pumps with flow rates up to 500gpm to knock down building fires quickly.
- Match the tank to the pump
There are no hydrants in the forest. Wildland engines won't do much good if they run out of water in the first minute or two of operation. In the examples above, tank capacities of 300 to 500 gallons are common for initial attack engines; 500 to 900 gallons are common for heavy attack engines. In general, tanks should be large enough to support continuous operation at the desired flow rates for five to 10 minutes — the longer, the better.
- Match the chassis to the load
Wildland agencies use a variety of truck chassis depending on the total weight of the pump, tank, water, hose, body, equipment and number of personnel. They know that overweight engines are unsafe engines, and they work with the apparatus manufacturers to select the appropriate chassis for a specific load.
- Keep it low
Positioning the tank, pump, hose reels and other components low on the body improves visibility to the rear and keeps the vehicle center of gravity low for better stability. It also makes all the components easier to reach.
- Keep it simple
Simple means lightweight; simple means less expensive; simple means easy to use. Flatbed trucks with skid-mounted pump and tank units make good wildland engines for many applications.
- Keep it safe
Whatever you do, keep it safe. Wildland engines fall under NFPA 1906, which sets requirements for side-slope stability, slip-resistant steps, warning lights, reflective markings and other safety considerations. Be especially aware of these requirements if your department decides to build its own wildland engine. (See sidebar, page 21.)
For photos and specifications of other federal and state wildland agency engines, see the “Water Handling Equipment Guide,” published by the National Wildfire Coordinating Group. The latest edition is available at www.nwcg.gov/pms/pubs/wheg03.pdf
Chris Cavette writes about apparatus and maintenance issues for Fire Chief.
The Roscommon Equipment Center is a cooperative program between the National Association of State Foresters and the Michigan Department of Natural Resources. It was founded in 1972 and is now widely recognized as a source of authoritative information on the conversion of military vehicles into wildland apparatus, as well as the installation of slip-on pump/tank units in pickup trucks.
The center provides numerous reports, guidelines, drawings, specifications and weight calculators to help departments build wildland engines that are both safe and effective. They also have information on nozzles, foam systems, fireline hand tools and other wildland firefighting equipment. Much of this material can be downloaded online at no charge.
For more information, visit www.RoscommonEquipmentCenter.com
If you are familiar with the NFPA 1901 requirements for structure engines, you may be surprised by some of the NFPA 1906 requirements for wildland engines. Wildland engines operate under different conditions than structure engines and they have different requirements.
Here are some of the key differences:
NFPA 1906 (Section 2.5.1b) requires a minimum vehicle side tilt of 27° to 30° for wildland engines depending on the gross vehicle weight rating of the chassis. NFPA 1901 has no side-tilt requirement.
NFPA 1906 (Table 3.3.2.2) specifies a minimum ground clearance of 9 to 12 inches and a minimum axle housing clearance of 6 to 10 inches for wildland engines depending on the GVWR of the chassis. NFPA 1901 (Section 12.3.2.2) requires a minimum of 8 inches for both ground clearance and axle housing clearance for all structure engines, regardless of the GVWR.
NFPA 1906 (Section 3.3.2.3) requires a minimum 20° angle of approach and departure for wildland engines, while NFPA 1901 (Section 12.3.2.3) requires a minimum 8° for structure engines.
For chassis with GVWR up to 26,000 pounds, NFPA 1906 (Table 3.1.1) requires lower weight allowances for miscellaneous equipment than NFPA 1901 (Table 12.1).
To order a copy of NFPA 1906, Wildland Fire Apparatus, call NFPA at 800-344-3555 or use their online catalog at http://catalog.nfpa.org.
Most wildland agencies use the bid process when they purchase apparatus. As a result, several different manufacturers may make the same model over the years.
Advanced Fabrications & Mfg.
303-466-1405, www.ad-fab.com
Boise Mobile Equipment
800-445-8342, www.bmefire.com
Cascade Fire Equipment Co.
800-654-7049, www.cascadefire.com
Mallory Fire
800-426-6830, www.malloryco.com
Master Body Works, Inc.
323-564-6901, www.masterbody.com
Phenix Enterprises
800-736-9790, www.phenixent.com
Pierce Mfg, Inc.
920-832-3231, www.piercemfg.com
Placer Fire Equipment Inc.
916-856-1818, www.placerfire.net
Rosenbauer America
605-543-5591, www.rosenbaueramerica.com
S&S Fire Apparatus Co.
800-247-3999, www.ssfire.com
Westates
530-661-0101, www.westates-body.com
West-Mark
209-343-3108, www.west-mark.com
Wildcat Fire Trucks USA
888-722-5070, www.wildcatfiretrucksusa.com
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