Like most fleets, specialized haulers have the same concerns over rising diesel fuel costs. But for Ellensburg, WA-based Anderson Hay & Grain Co., which utilizes intermodal chassis to transport hay and straw to the ports of Seattle and Tacoma for overseas shipment, the options were limited.

“The price of diesel started doing really silly stuff [in 2009], and there are all sorts of things out there like super singles” but not much for intermodal chassis, says Alan Fife, facilities manager for the family-owned business. “I started doing some research.”

Fife saw that side skirts were generating fuel savings for many dry van and refrigeration fleets, but there were no options available for his company’s four-axle intermodal chassis trailers. But conversations with Freight Wing and Grandview, WA-based manufacturer Dionbilt Trailers resulted in a solution.

“I just wanted a product that was made for a chassis and was going to stand up to [tough operating conditions],” says Fife.

Anderson Hay has since installed the skirts on 27 “outbound” 46-ft. chassis trailers.

The hay and straw Anderson hauls is grown at a network of company-owned facilities and family-owned farms throughout the region. It utilizes flatbeds to haul hay bales inbound from the fields to facilities where it is “double compressed” for overseas shipping in containers. The compressing process allows the fleet to pack more product into a container, says Rodney Van Orman, operations manager. The intermodal tractor-trailers typically run at 102,000 lbs. covering 450 mi. a day, he says.

According to Freight Wing, the payback for the side skirts could be as few as 35,000 mi., mere months for many fleets. Fife says his company saw payback in nine months.

One issue that needed to be addressed was how to attach the skirts to the intermodal chassis. Freight Wing’s solution was to clamp the skirts to the I-beams just below where the intermodal box rests, says Sean Graham, president of the Seattle-based aerodynamics company. Graham notes that the two-piece skirts are flexible and hinged to the trailer via fiberglass rods, allowing them to bend and flex to prevent damage.

Freight Wing will offer the skirts, available commercially this month, in two styles. One utilizes the company’s dense matrix polyethylene material, which includes “bounce back” to allow it to absorb abuse. The other is a composite material. According to Graham, the composite skirts have a low coefficient of thermal expansion, allowing them to hold their shape to give the skirts a clean, mirrored look. They will be available for most intermodal trailer lengths.

Fife says Anderson Hay has seen an improvement of between 0.4 and 0.6 mpg since installation. Combined with other fuel-efficiency initiatives, Van Orman says the fleet has seen approximately a 1 mpg improvement overall. Among those efforts were the installation of roof fairings, driver training offered by Peterbilt and Cummins, setting max speed at 62 mph and idle times at 10 min. in the winter and 5 min. in the summer, and the use of fleet management software from Sage Quest.

“We’ve definitely seen changes in driver habits in the way they are driving the equipment,” says Teena Gruber, operations dispatch supervisor.

At this point, Fife is estimating the fleet will see significant savings from the skirts. “I could see them lasting five-plus years easy,” he estimates, “and for the price, that’s a pretty good lifecycle for me.”