This invention provides a water craft hull having an air chamber, wherein the sidewalls of the air chamber extend lower than the fore wall and the aft wall of the air chamber, and wherein the hull comprises at least one air injector configured to deliver pressurized air to the air chamber. Optionally, a hull of the invention has a high aspect ratio air chamber defined by a stable fore wall, a stable aft wall, and stable sidewalls, is a non-planing hull, has a wave-piercing bow, and has elongated keel fins (e.g. inner keel fins and/or outer keel fins). Optionally, the air chamber is configured for recirculating air flow.

A boat hull having a ventilated boat keel is disclosed. In one embodiment, the ventilated boat keel may be a longitudinal vent tube from bow to stern, which runs down the center of the hull and branches off into multiple vent openings along the stepped hull. In another embodiment, the ventilated boat keel may be a longitudinal vent tube from bow to stern, which runs down the center of the hull and branches off into multiple vent openings along a traditional hull design. The ventilated boat keel creates a layer of micro-bubbles along the bottom of the boat. The micro-bubbles reduce friction and drag and allow for the boat to travel at a higher rate of speed using less fuel.

A boat hull having a ventilated boat keel is disclosed. In one embodiment, the ventilated boat keel may be a longitudinal vent tube from bow to stern, which runs down the center of the hull and branches off into multiple vent openings along the stepped hull. In another embodiment, the ventilated boat keel may be a longitudinal vent tube from bow to stern, which runs down the center of the hull and branches off into multiple vent openings along a traditional hull design. The ventilated boat keel creates a layer of micro-bubbles along the bottom of the boat. The micro-bubbles reduce friction and drag and allow for the boat to travel at a higher rate of speed using less fuel.

A grounding skeg for a landing craft configured for stem landing onto, and setting off from, a ground surface, the grounding skeg including: an elongate grounding body having a fore end and an aft end; and a removable pulling propeller functionally connected to the fore end of the body; wherein the pulling propeller is able to drive the landing craft ahead and astern; and the grounding body is locatable on the landing craft such that; the grounding body provides contact with the ground surface during stem landing of the landing craft; the fore end of the grounding body faces a bow end of the landing craft; and the aft end of the grounding body faces a stem end of the landing craft.

A grounding skeg for a landing craft configured for stem landing onto, and setting off from, a ground surface, the grounding skeg including: an elongate grounding body having a fore end and an aft end; and a removable pulling propeller functionally connected to the fore end of the body; wherein the pulling propeller is able to drive the landing craft ahead and astern; and the grounding body is locatable on the landing craft such that; the grounding body provides contact with the ground surface during stem landing of the landing craft; the fore end of the grounding body faces a bow end of the landing craft; and the aft end of the grounding body faces a stem end of the landing craft.

A skeg mounts from the stern of a towing vessel and extends below the waterline. A channel in the skeg protects cables for steamers and a source (e.g., air gun array) of a seismic system deployed from the vessel. Tow points on the skeg lie below the water's surface and connect to towlines to support the steamers and the source. A floatation device supports the source and tows below the water's surface to avoid ice floes or other issues encountered at the water's surface. Seismic streamers have head floats supporting the streamers. Each of the floats has adjustable buoyancy preconfigured to counterbalance the weight in water of the towed component that the float supports. Acoustic signals from a transceiver at the vessel find locations of the towed components. A towed fish at a lower level than the towed components also uses acoustic signals with a transceiver to further refine the locations of the towed components.

A skeg mounts from the stern of a towing vessel and extends below the waterline. A channel in the skeg protects cables for steamers and a source (e.g., air gun array) of a seismic system deployed from the vessel. Tow points on the skeg lie below the water's surface and connect to towlines to support the steamers and the source. A floatation device supports the source and tows below the water's surface to avoid ice floes or other issues encountered at the water's surface. Seismic streamers have head floats supporting the streamers. Each of the floats has adjustable buoyancy preconfigured to counterbalance the weight in water of the towed component that the float supports. Acoustic signals from a transceiver at the vessel find locations of the towed components. A towed fish at a lower level than the towed components also uses acoustic signals with a transceiver to further refine the locations of the towed components.

A modified V-hull boat has a keel starting at about 20% from the bow ending 75 to 80% aft of the bow and has an inverted airfoil shape. A flat pad blends in aft of the keel assisting planning and attitude at speed. A bracket having a bottom shape and size to float a designated amount of weight and a downward angle facing down at the aft on the bottom to act as a positive planning fixed trim tape that ride's above the water at speed or on plane, and adds stability and positive buoyancy for weight of engines at rest or low speed. Chine's are the outside corner of the boat joining the bottom to the side's. The chine's taper slightly inboard aft to relieve friction and drag. Although they do not come together the chine is no way a straight line the outer edges are slightly more ellipsoidal hence the name.

A modified V-hull boat has a keel starting at about 20% from the bow ending 75 to 80% aft of the bow and has an inverted airfoil shape. A flat pad blends in aft of the keel assisting planning and attitude at speed. A bracket having a bottom shape and size to float a designated amount of weight and a downward angle facing down at the aft on the bottom to act as a positive planning fixed trim tape that ride's above the water at speed or on plane, and adds stability and positive buoyancy for weight of engines at rest or low speed. Chine's are the outside corner of the boat joining the bottom to the side's. The chine's taper slightly inboard aft to relieve friction and drag. Although they do not come together the chine is no way a straight line the outer edges are slightly more ellipsoidal hence the name.

A watersports boat includes a hull having an underside that defines a running surface that contacts water when the hull moves therein. The running surface includes a planing mode trailing edge and a pre-planing mode trailing edge. An aft running surface section of the hull includes port and starboard recesses that extend from a respective step at a forward end thereof aft to a respective aft edge thereof. The steps form the planing mode trailing edge where water disengages from the aft corners of the aft running surface section when the boat travels in planing mode and the aft edge of the recesses form the pre-planing mode trailing edge where water disengages from the aft corners of the aft running surface section when the boat travels in pre-planing mode.