A trailer tail, boat tail, or rear fairing is an aerodynamic device intended to improve the fuel economy of semi-trailer trucks. It comprises a set of panels, usually collapsible, which fold out from the rear of the trailer, creating a tapered shape that reduces drag from the low-pressure wake created behind the trailer. Trailer tails are one form of aerodynamic technology verified by the U.S. Environmental Protection Agency's SmartWay Transport Partnership. Trailer tails alone have demonstrated a fuel savings of 1%–5%, and in concert with trailer skirts, 9% improvement has been demonstrated.
At least one model of trailer tail, trade named TrailerTail, is part of Navistar's SuperTruck project, which will use $37 million of US Department of Energy grants to build next generation trucks and tractor trailers.
- "Learn About SmartWay Verified Aerodynamic Devices". U.S. Environmental Protection Agency. Retrieved 29 June 2016.
- "SmartWay Verified List of Aerodynamic Devices". U.S. Environmental Protection Agency. Retrieved 29 June 2016.
- "TrailerTail® Fuel Savings Technology". stemco.com. Retrieved 2018-10-15.
- Navistar SuperTruck Archived July 17, 2011, at the Wayback Machine