A braking system for waterborne propeller driven vessel which, upon activating a brake pedal or similar actuation device causes the vessel to almost immediately stop its forward movement. The system initiates a burst of highly amplified horsepower and torque, created by a controlled pulse of electrical power released from a bank of fully charged ultracapacitors. This pulse of electrical power is sent directly to AC induction-driven motors, causing oversized propellers to immediately rotate astern, thereby generating a reverse thrust in opposition to the vessel's forward movement sufficient to stop the vessel. The horsepower and torque produced by the braking system and operation of the present invention will also cause the oversize propellers to transmit this tremendous power into the water, without cavitation, to assist in stopping vessel movement.