Abstract: A capstan winch includes a reel assembly comprising a reel, which rotates, and two generally annular floating flanges which are supported so that the planes in which they rotate converge toward one another, which has the effect of creating an apparent axial movement of the flanges with respect to the reel as they rotate together. The cylindrical surface of the reel is provided with alternating lands and grooves and floating flanges have formed on them alternating inclined faces which correspond with the lands and the grooves. The inclined faces are angled so that the faces which correspond to each land on the reel are generally parallel to one another. The inclined faces which correspond to each groove converge. Consequently, substantial lateral forces are exerted on a cable being wound onto the reel only when the cable overlies the grooves and frictional forces on the cable are minimized.

Abstract: A capstan winch (10) includes a reel assembly comprising a reel (12), which rotates, and two generally annular floating flanges (20) which are supported so that the planes in which they rotate converge towards one another, which has the effect of creating an apparent axial movement of the flanges with respect to the reel as they rotate together. The cylindrical surface of the reel (12) is provided with alternating lands (19) and grooves (18) and the floating flanges (20) have formed on them alternating inclined faces (26 and 24) which correspond with lands (19) and grooves (18). The inclined faces (24 and 26) are angled so that the faces (26) which correspond to each land (19) on the reel (12) are generally parallel to one another. The inclined faces (24) which correspond to each groove (18) converge. Consequently, substantial lateral forces are exerted on a cable being wound onto the reel (12) only when the cable overlies the grooves (18) and frictional forces on the cable are minimized.

Abstract: A fairing for reducing the drag produced by a lead-in cable which is being used to tow one or more seismic streamers forming part of a wide streamer array comprises a plurality of fairing sections, each having a central bore to receive the lead-in and a streamlined profile. The sections are coupled together end-to-end by swivel couplings which permit rotation of the sections relative to each other, so that each section can adopt the optimum orientation for drag reduction. Drag reduction is further enhanced by providing the upper and lower surfaces of the leading edge of each fairing section with respective sets of longitudinally extending ridges/grooves.