Chassis Components, Fire Department, Special Operations Hazmat

Skid Units: Making the Most of Smaller Packages

Issue 7 and Volume 19.

By Alan M. Petrillo

Fire departments around the country, but especially in the West, Southwest, and Midwest, are fitting out small, easy-to-maneuver vehicles with skid units that are useful not only for wildland fires but also in urban interface situations.

Skid Unit Evolution

Jerry Halpin, vice president of sales and marketing for CET Fire Pumps, says that skid units have come a long way in the past 40 years. “Most of the innovation today is found in the pump and its capacity, both in pounds per square inch (psi) and gallons per minute (gpm), and in the application of different agents such as foam and other types of wet water that might not have been available even 15 years ago,” he says.

Such units, called both skids and drop-ins, are not terribly large in terms of size or weight, Halpin observes. “They are much more efficient than ever before, can be put on a wider variety of vehicles that only carry a limited amount of weight, and have more firepower and gpm available,” he points out.

CET Fire Pumps makes a series of what Halpin calls “quick-delivery skid unit models,” from the basic Econo Pac with a pump capacity of 20 gpm at 125 psi and 60-gallon water tank to the Attack Pac, carrying a 20-horsepower midrange fire pump that delivers 265 gpm at 50 psi, 190 gpm at 100 psi, 115 gpm at 150 psi, and 45 gpm at 200 psi. The Attack Pac also has a 200-gallon fully baffled polypropylene water tank. Other CET skid units are the Ready Pac, Skeeter Space Pac, and Ultra Power Pac.

Typically, CET skid units are powered by six-, nine-, 11-, or 20-horsepower (hp) gasoline engines, although diesels are available for some skid unit models. The skids are most often mounted on Ford chassis, Halpin says, from F-150 to F-550 models.

Fast Attack 2 skid unit
1 W.S. Darley Company makes the Fast Attack 2 skid unit, available with a variety of Darley pumps and water tank sizes and with the Foam Flurry around-the-pump-foam system. (Photo courtesy of W.S. Darley Company.)

In using skid units, Halpin notes, the issue continues to be “applying the right amount of water at the right psi.” He continues, “And especially in forestry work, it is getting into remote places to create a fire stop where the fire won’t be able to burn through or to use a skid unit to extinguish hot spots.”

Skid Pumps

Jason Nawrocki, OEM sales manager for Waterous, says his company has been seeing an increase in both inquiries and purchases for pumps being used in skid unit applications on smaller fire apparatus. “There are so many different styles of apparatus in how you fight a fire, particularly a wildland fire, that require a more tactical response with 4×4 vehicles, often with pump-and-roll capability,” Nawrocki says. “In many of those cases, the slide-in skid unit is the way to go because it allows the fire department to be more agile and tactical in its response.”

Nawrocki says that the increased interest in Waterous pumps for skid units “comes from all around the country but is pretty dense in the western United States and Canada, likely because of the drought.”

For skid units, Waterous makes the PB series pumps, with an 18-hp gasoline-powered Briggs & Stratton engine, in both volume and pressure versions. Its diesel series, the E300, is an end-suction 300-gpm-capable pump powered by a Kubota engine.

“Our most popular skid unit is the E500 series, a 24.8-hp Kubota diesel with an electronically controlled throttle,” Nawrocki says. “We sell a lot of the high-pressure E501 wildland models in the western United States.”

CAFS for Skids

Compressed air foam systems (CAFS) are being incorporated into skid units, Nawrocki notes. “We developed an all-new CAFS called the Waterous ONE STEP™ CAFS that can be integrated into skid unit technology,” he says. “ONE STEP uses compact foam generators that deliver a fixed compressed air foam product every time the unit is used.”

Nawrocki says ONE STEP uses a touch screen “human-machine interface, which is the same screen used in the F-22 fighter jet. It’s easy to use and understand, the graphics are inviting for the end user, the screen can be read in direct sunlight, and it has been impact tested.” He adds, “ONE STEP CAFS allows a firefighter to stay in the fight longer, use water more wisely, and go much farther, which is important in wildland fires where you don’t have a lot of accessibility to water.”

Waterous
2 Waterous often supplies its ONE STEP CAFS to be integrated into a fire department’s skid unit. ONE STEP uses compact foam generator technology and is controlled by a touch screen. (Photo courtesy of Waterous.)

Sales Increasing

Dan Kreikemeier, president of Danko Emergency Equipment, says his company has been building a lot of skid units in recent months. “We’re sending out a couple of skid units a week,” he points out, “complete with all stainless steel plumbing and in both diesel- and gasoline-powered versions. Our units are plug-and-play, where you get the engine and pump with the outlets set up for a reel, brush lines, or other discharges.”

Danko’s typical skid unit is the Brushwacker, carrying an 18- to 20-hp Honda or Briggs & Stratton engine and a 250-gallon water tank. “It has a good wildland capability,” Kreikemeier says, “but it’s also useful for vehicle fires and for a quick knockdown.”

Foam Use

Troy Carothers, AutoCAFS manager for W.S. Darley Company, says Darley has been selling more skid units directly to fire departments compared to original equipment manufacturers (OEMs). “We don’t do the cookie-cutter rigs; we’re usually doing more specialty versions with slightly different tanks or foam systems or CAFS,” Carothers says.

Darley’s Fast Attack skid units are assembled at its Odin-Ohler plant in Janesville, Iowa, where all its foam-based products, like the Mongoose and Derringer units, are built. “Ninety percent of the time we’ll build a skid unit and dispatch it to a fire department,” Carothers points out. “Rarely does the department go there with its vehicle to hook it up.”

Darley’s Fast Attack 1 skid unit comes with options such as a preconnected hose tray, Scotty foam proportioner and built in foam cell, and with a wide range of Darley Davey pumps. Its Fast Attack 2 is built with the Darley line of pumps with all options available like the Foam Flurry around-the-pump system or the Darley Fast Foam 50 system.

UHP for Skids

Danko also developed the AquaVantage ultra-high-pressure pump, a small unit that can produce 20 gpm at 1,200 psi. Kreikemeier notes the unit can be throttled down to simply apply a layer of foam. “We also have an option as a dual-purpose unit,” he says, “giving 20 gpm at 1,200 psi and, after flipping a switch, volume operation at 120 gpm at 150 psi.”

Carothers says Darley recently put its ultra high pressure-high volume (UHP-HV) skid unit on a Ford F-350 chassis with a 250-gallon water tank and 25-gallon foam tank. “We added a Darley 2BE pump that gives 120 gpm at 130 psi as a separate pump from the UHP-HV unit, which because of its high pressure and high volume, has a low usage of water.”

Small Vehicle Application

Kimball Johnson, president of Kimtek Corp., says his company started out designing and building skid units like its FireLite line as slip-ons for utility terrain vehicles (UTVs). “Several years ago we got into the pickup truck market with our FireLite pickup truck series-short-bed vehicles carrying 125 to 160 gallons of water and one of our skid units.”

Tsunami skid unit
3 MTECH makes the Tsunami skid unit designed for use on light trucks like this Ford F-150, shown with two hose reels and slide-out trays. The Tsunami uses a Honda-powered engine and typically a Darley Davey fire pump with up to a 500-gallon water tank. (Photo courtesy of MTECH.)
MTECH QTAC skid
4 UTVs are becoming popular with some fire departments for getting into places that even light trucks fitted with skids can’t negotiate. This UTV has a MTECH QTAC skid unit with a Darley Davey 5.5-horsepower pump and an 85-gallon water tank. (Photo courtesy of MTECH.)

Wade Meith, director of business development for MTECH Inc., says his company builds skid units that fit UTVs and pickup-sized vehicles, such as a QTAC for a Polaris 6×6 UTV or a Tsunami for a Ford F-150. “Everything we do is Honda-powered, but the pump is determined by the application,” Meith says. “For fire service work, we use either a Darley Davey or a Koshin, generally starting in the 5.5-hp range.”

Johnson says the FireLite skid units he builds for UTVs have 55-, 75-, or 85-gallon water tanks, depending on the chassis they’re going on. “Our best seller is a unit driven by an AK304 5.5-hp Honda pump and a Darley Davey manual-start pump,” Johnson notes. “On units with bigger water tanks, we’ll put on a nine-hp electric start Darley Davey with manual backup or even a 13-hp model.”

Kimtek FireLite skid unit
5 The Magee Fire Department, in Seneca Falls, New York, put a Kimtek FireLite skid unit with a single hose reel and a Darley Davey pump on its pickup truck. Kimtek supplies water tanks from 125 to 160 gallons for its pickup truck skid units. (Photo courtesy of Kimtek Corp.)
Supermax FST-204
6 Kimtek also makes its FireLite series of skid units for UTVs, like this Supermax FST-204 unit on a Polaris Ranger 6×6. The rig also has provision for carrying a Stokes basket or backboard. (Photo courtesy of Kimtek Corp.)

FireLite skid units are built with all stainless steel plumbing and aluminum tubing, Johnson says. Options include Scotty around-the-pump foam systems and additional hose reels.

Meith says a fire department recently purchased a Tsunami skid unit from MTECH and installed it on a pickup truck. “Two hours after they installed it, the firefighters used it to put out a fire in an excavator,” he notes. The skid unit has a 5.5-hp Darley Davey and carried 500 gallons of water.

Other Trends

Carothers sees a trend among wildland skid unit users for numerous control positions. “They want to be able to do pump and roll from inside the cab and outside,” he points out, “and we’re seeing more remote control capabilities and iPhone capabilities. It’s important when you’re down in a valley with 200 feet of hose out and want to ramp up the engine.”

In very arid areas where water is the chief concern, MTECH’s customers generally want a large-capacity water source on a skid unit, Meith observes. “They often want upward to 500 gallons but may elect to go with a smaller- sized pump at 5.5 to six hp. In our Tsunami line, tanks between 150 gallons and 500 gallons of water are typical, and pumps run from 5.5- to 26-hp, generally Darley Davey or Briggs Vanguard. The customer defines the specs of what’s needed and we respond to that.”

Halpin points out that many fire departments recognize the greater versatility of a skid unit mounted on a lighter vehicle compared with a midmount vehicle pump or a PTO-powered pump platform. “Since a skid unit is self-powered and self-contained, it’s not chassis-dependent,” Halpin says. “If the chassis is incapacitated and is of no value, the skid unit can be removed and installed on another vehicle. From a return on investment (ROI) standpoint, the ROI is infinitely higher with a skid unit.”

ALAN M. PETRILLO is a Tucson, Arizona-based journalist and is a member of the Fire Apparatus & Emergency Equipment editorial advisory board. He served 22 years with the Verdoy (NY) Fire Department, including in the position of chief.