A system and method for aerodynamic fairings including an undercarriage fairing. The undercarriage fairing includes multiple panels including at least two front panels and at least two rear panels. The at least two front panels are connected in a front portion under the trailer. The at least two rear panels are positioned in front of a wheel undercarriage at sides of the trailer. One of the at least two front panels and one of the at least two rear panels are interconnected on both sides of the trailer. The undercarriage fairing further includes supports connected to the frame of the trailer. The supports are connected to the at least two rear panels.