Abstract: This invention introduces a unique two-piece nozzle used to provide air to the hull bottom of a ship, reducing the drag of water friction while in motion. The unique base assembly will mount flush in the bottom portion of a hull of a ship, creating no additional drag when closed. The unique interchangeable and modular nozzle design will allow for maintenance and or development of various designs in the water, without requiring a drydock visit. A flap portion of the nozzle insert will open when air is supplied, releasing small air bubbles to a ship's hull. The flap portion of the nozzle insert may incorporate various materials and passive closing schemes to adjust the air plastron. The present invention creates and maintains an air curtain, called plastron, delivering air underneath a ship hull through an array of nozzles.