A mechanism to alter the flight path of a projectile after launch. A plurality of fins are disposed around the projectile and are held in place by one or more caging wires, depending on fin design. In one embodiment, auxiliary fins are connected to adjacent main fins which are held in a stowed position. When released, the fins deploy and present a continuous surface to the airstream for maximum braking action. In another embodiment, each fin is divided into fin segments which are individually deployable to alter the spin or course of the projectile by deflection. Additionally, all of the fins may be deployed to provide a braking action. All of the fins are tied together to distribute and reduce encountered loads when deployed.