Deliberate slips done with vigorous application of roll and opposite rudder (lower the right wing and step on the left rudder) can be used as a dive brake. By balancing the roll's turn to the right with the rudder's yaw to the left, the plane continues to fly straight ahead but it presents its side rather than its nose to the airstream. The drag from this aerodynamically "dirty", clumsy position slows the otherwise sleek airplane.