A system for improving the performance of a powered boat that includes both methods and apparatuses that provide a powered boat ways to stabilize, control, and optimize the powered boat's performance when the powered boat is in powered motion. The system provides capabilities of enhancing the powered boat's performance by responding to both aerodynamic and hydrodynamic effects upon the powered boat when the powered boat is in motion. Some embodiments of the system are capable of altering its way of responding to aerodynamic effects while the powered boat is in powered motion, other embodiments are capable of altering the powered boat's response to hydrodynamic effects while the powered boat is in powered motion, and still other embodiments are capable of altering the powered boat's response to both aerodynamic and hydrodynamic effects while the powered boat is in powered motion. Certain embodiments of the system are capable of utilizing aerodynamic elements that operate on the air stream flowing within a tunnel formed within a multihull of a powered boat, while other embodiments are capable of mitigating the effects of water impacts upon the roof of a tunnel formed within a multihull powered boat. Still other embodiments are capable of responding to aerodynamic effects by interacting with portions of the air stream that passes above the boat while mitigating the potential for negative effects due to cross-winds impacting the structure which rises above a deck of the powered boat.