The skirts are attached to the trailer ahead of its wheels, where they divert air to reduce the turbulence and drag that wastes fuel. They're usually made of materials such as aluminum, rubber, or fibreglass.20 Feb 2019
Why do trailers need skirts?
Trailer fairings, frequently referred to as trailer skirts, are the most popular devices for addressing aerodynamic drag on trailers. They prevent wind from ducking in under the trailer and running into the trailer bogie.
Why do some semi trailers have side skirts?
A side skirt, which fits between a semi-truck's front and rear wheels, helps improve aerodynamics and is not intended for protection. Side skirts are usually made of fiberglass, aluminum or plastic, to give them flexibility, and reportedly improve fuel economy, which is why they're used on large trucks hauling freight.20 Nov 2017
Do trailers Need side skirts in California?
Under the rule, all 53-foot box-type trailers (dry or refrigerated) must be equipped with Environmental Protection Agency SmartWay-approved side skirts or tail fairings that improve fuel economy from 4% to 5%, in addition to low-rolling-resistance tires (either standard or wide-base singles).26 Jan 2016
What are the side skirts on trailers?
NRC says, "Trailer side skirts are a set of panels that run the length of the trailer to extend it closer to the ground." The devices "provide a 4 to 7 percent fuel savings by minimizing the air flow under the trailer and around the back axle." There is also a chart showing the average payback period.
Why do semi truck trailers have side skirts?
Whatever you call them, their purpose is to reduce drag and save fuel. According to Susan King, a spokesperson for the American Trucking Associations, side panels “reduce drag on the undercarriage and wheels of the rig, thereby improving fuel efficiency,” while tail fairings reduce drag around the rear of the vehicle.3 Apr 2013
What are truck skirts for?
The skirts are attached to the trailer ahead of its wheels, where they divert air to reduce the turbulence and drag that wastes fuel.20 Feb 2019