Aerodynamic Speed Stacks
King Air exhaust pipes might appear as a source of excessive drag. Our analysis confirmed that the standard pipe shape is aerodynamically dirty and not properly aligned with the airflow.
Our new Aerodynamic Speed Stacks are designed to reduce drag while keeping the aircraft cleaner. The original King Air stack is actually the same exhaust used in four different positions in relation to the longitudinal axis of the aircraft, which creates a high drag profile. American Speed Stacks are manufactured as four distinct stacks with different flange hole locations for each position so they can be clocked to their most aerodynamically correct positions. Speed Stacks not only look sleek and fast, they are. As a result of the new shape, airspeeds are increased from 4 to 8 knots and the boundary layer relief is improved, meaning more exhaust residue will be blown clear of the airframe.