The XR airfoil is CAD (computer aided designed) designed to be the most efficient possible. The XR combines speed, stability, maneuverability, recoverability, and inverted flight. The XR has several degrees of washout to eliminate the dreaded “tip-stall” and maintain control. The internal spar design on the XR maximizes strength and durability. Unlike surface mounted spars, internal spars do not disrupt the airflow or the shape of the airfoil. The internal spar translates to a stronger and faster wing along with easier construction. The XR is simply the best 48” standard chord wing available.