A side panel for a recreational vehicle, such as a snowmobile is disclosed. The side panel extends from the windshield portion of the snowmobile to the pan portion. The side panel is hingedly attached at a front edge to the snowmobile so that the side panel opens outwardly along vertically oriented hinges. The side panel includes a windshield to protect the operator's legs. The side panel also includes an airbox which provides an air charge to the engine for combustion. In addition, an airbox, divisible into two parts is also disclosed. The airbox includes a portion adapted to be attached to the interior of the side panel or to a belt guard. A second portion of the air box can be disposed within the engine compartment.