A powerboat with a rooster tail depressor (RTD) includes a hull, a propulsion subassembly on the hull, and a rooster-tail-suppressing canopy on the stern that includes a downwardly facing surface no less than six inches above the dynamic water line of the stern where it functions to suppress the powerboat rooster tail for radar signature reduction and increased propulsion efficiency. Various embodiments include one or more of (i) a canopy having a downwardly facing surface that is arched (either curved or faceted), (ii) lift-to-drag ratio enhancing steps in the downwardly facing surface of the canopy, (iii) a rooster-tail-suppressing subassembly configured to enable articulation of the canopy in yaw and in trim, and (iv) operator-controlled port and starboard venting arrangements on the canopy that result in desired laterally directed thrust for enhanced maneuverability.