4 centimeters and length of 100 inches 254 centimeters the riser section has buoyancy modules that are ellipitcal with the outer diameter varying from 38 inches 96 52 centimeters to 40 inches 101 5 centimeters the nose portions of the fairings are sized to accommodate a 40 inch 101 5 centimeter buoyancy module the distance between the tail portions of the fairings when mounted on such a buoyancy module is 3 inches 7 62 centimeters under these conditions if the fairings are aligned along the minor axis 96 52 centimeters diameter and are not restrained in accordance with this invention from rotational movement of the fairings 39 longitudinal axes with respect to the riser section 39 s longitudinal axis the fairings 39 longitudinal axes can rotate approximately one degree from or out of parallel alignment with the riser section 39 s longitudinal axis this one degree of misalignment results in the tip of each fairing 39 s tail moving either up or down approximately 1 7 inches 4 3 centimeters thus if two adjacent fairings spaced 3 inches 7 62 centimeters apart at the tails are caused to rotate around the riser section in counter directions the fairing tails could interfere with each other fig4 5 illustrate another embodiment of a fairing of this invention showing another means for pressing bearings located on the down current side of the fairing against buoyancy module 13 to ensure that the longitudinal axis of the fairing 39 s nose position is maintained substantially parallel to the longitudinal axis of the riser section 10 fairing 120 is similar in construction to fairing 20 of fig2 3 except that rollers 128 and 129 provide bearing contact between the fairing and buoyancy module 13 and each fairing shell has two upstanding ribs.