Have you noticed the unusually shaped pieces extending out from the back end of a semitruck? These pieces, along with the flaps that hang between the front sets of tires and the back sets of tires work to create increased efficiency in tractor trailers on the interstate. Without these things, life on the road can be a total drag. Literally.

Air Resistance, Drag, and Fuel Efficiency

A quick physics brush up, which you most likely remember from high school class: The force that exists on an object that is resisting its motion through a fluid is called ‘drag.’ If this fluid is a gas, such as air, the drag is called aerodynamic drag, which is more commonly referred to as air resistance. Drag pushes in the opposite direction of the motion of the object. The object in the case of this article affected by drag is the tractor trailer.

Large tractor trailers that carry over 70% of American goods are notorious for consuming a large amount of fuel. As these trucks travel thousands of miles daily across our interstates, they push against the air and resistance is created. Aerodynamic drag is created when tractor trailers hit speeds of 60+ miles per hour. The drag creates resistance which causes the trucks to burn over 50% of their fuel when they transport across the country. In order to counteract these high levels of resistance, truck manufacturers have engineered additions to the tractor trailers to reduce wind resistance. This is fabulous news for fleet managers and environmentalists alike.

Aerodynamics in Tractor Trailers Promote Efficiency

In order to work with the natural physics of higher speeds traveling down the freeways, engineers have designed additional parts for the trucks which can reduce air resistance and increase fuel efficiency. Some of these additions which are often seen on tractor trailers today include:

  1. Skrrt, skrrt – These panels, referred to as skirts, are added underneath the trailers, between the front and back sets of wheels reduce the air that flows around the undercarriage of the trailer. These measures increase fuel efficiency by 4-7% and run the length of the trailer. The manufacturers designed these skirts out of aluminum, plastic, or fiberglass with plastic being the most resistant to damage from impacts to the sides or bottoms.
  • Mind the Gap – Several manufacturers have been able to reduce resistance by as much as 6% by creating a device that can completely cover the space between the tractor and the trailer. These gaps have often measured 18 inches or more! By covering this gap with a large piece of manufactured plastic inserted between the sets of tires, fuel savings is increased by 2%. (insert photo)
  • Hoist the Mizzens – Boat tails, also known as rear fairing and trailer tails, are the extra flaps that are attached at the back end of the tractor trailer. These tails reduce turbulence behind the square rear end. Boat tails are thin, collapsible pieces of thermoplastic composite material that fold out from the rear of the trailer, 24-32 inches in length. These create a tapered shape from the air moving around the truck and can save more than 6% on fuel costs when traveling at 65 miles per hour.

Collectively, these measures reduce drag on the trucks and truck manufacturers are continually looking toward future technology to continue these improvements. There are additional measures such as external mirror elimination by using camera solutions throughout the semitruck can also provide additional fuel reduction. Another change which can improve efficiency is the use of lighter materials in manufacturing, such as carbon fiber and composites with the goal of lightening the trucks overall. These as well as bumper closure, adding an air dam, a hood-to-bumper fill, and integrated camera systems instead of bulky mirrors are making strides in efficiency technology and the trucks overall impact on the environment. With Amazon’s recent announcement of same-day and one-day shipping, the roads are only going to see increased traffic of logistical travel. The trucking industry is responding in kind by continually working to advance technology to improve the number one transporter of products.

Good News for Tractor Trailer Fleet Owners

Fleet owners can take advantage of newer truck models that cut down on fuel consumption, while creating the opportunity for increased environmental awareness within the industry. While working to update these additions to your tractor trailers, remember to keep your trucks running smoothly by scheduling regular maintenance with a trustworthy mechanic. Combining truck skirts, boat tails, and decreasing the gap between the tires along with a well-maintained semi can make the reduction in costs in your fleet management.

Diesel Mechanic in East Tennessee

If you’re looking for a reliable mechanic for your truck or fleet, Certified Diesel Solutions provides quality, dependable service. We remain current with technological updates including the additions which improve the efficiency of your truck. Our mechanics are equipped, trained, and certified to keep your fleet running. Reach out by calling 865-964-6598 to schedule your next fuel filter change, for assistance with a host of additional diesel engine maintenance options, or to discuss ways to ensure your trucks are running as efficiently as possible.