a hydrofoil sailboard comprising a conventional sailboard , without the usual tail skeg , equipped with two hydrofoils arrayed in a canard configuration , the combined lift of the foils being sufficient to hold the board clear of the water at operational speeds . the main foil , mounted beneath the rear of the board is designed to ride fully submerged and to support the bulk of the weight of the board and sailor . the much smaller canard foil , mounted beneath the front of the board is designed to ride at or near the water surface , and its purpose is control and balance . the main foil is connected to the board by a supporting foil which is provided with ventilation fences . the canard is rigidly connected to the board by a support comprising a rod about which a streamlined fairing is free to swivel . a seal between the fairing and the rod prevents airflow to the canard along the inside of the fairing . the purpose of the swiveling fairing is to eliminate canard ventilation along the outside of the support , to reduce drag , and to enhance steering . the canard is designed to rapidly shed air bubbles that may lodge on it when it is submerged .