Complex sentence: The DynaRig concept calls for an elongated section (to reduce the drag) and this needs to be symmetrical as the rig can be tacked to allow flow in both directions, the mast rotates about deck and heel bearings.
Split into simpler sentences: The DynaRig concept calls for an elongated section (to reduce the drag) and this needs to be symmetrical. As the rig can be tacked to allow flow in both directions, the mast rotates about deck and heel bearings.