Abstract: A surface effect drilling craft or hovercraft is provided for taking continuous core samples in normally inaccessible environmentally sensitive regions such as wetlands. The hovercraft includes an inner hull including an inner hull floor and a bottom hull disposed beneath the inner hull and a base mounting plate secured to the inner hull floor. A drill tube extends through the base mounting plate, inner hull floor and bottom hull. A drill rig including a multi-sonic drill is mounted on the base mounting plate adjacent to the drill tube. The drill rig includes a fixed lower section, and a pivotable upper section movable between an erected, operative position for drilling and a collapsed, inoperative position during maneuvering of the hovercraft. A drill cap is used to close off the drill tube during this maneuvering.