A stabilized watercraft having a pointed bow, a transom and curved sides, and a rigid buoyancy tube which extends from the bow to a point past the transom. The tube has a cross-section which is approximately rectangular, but is generally somewhat wider in a lower portion than in an upper portion thereof over at least an aft portion of the boat. The tube has a dead rise in the range of 0° to +15° with the upper surface of the tube being flared outwardly in the range of 30°-80° at the bow portion of the watercraft and an angle of 60°-80° at the stern portion.