A seismic survey system includes a winch having a winch cable coupleable
to a source array towable between two deflected lead-ins, a positioning
system for determining a current position of the source array and a
controller for adjusting the winch to modify the current position of the
source array to a desired crossline position. The winches may be attached
to the deflected lead-ins or mounted on a tow vessel. The winches exert
lateral forces on the source array, derived from the deflected lead-ins,
to control the inline position of the source array. A method includes
positioning a seismic source array in tow behind a vessel comprises
determining a current position of the source array and adjusting a
lateral force applied to the source array to move the source array to a
desired crossline position. Optionally, by adjusting the gun cable winch,
the inline position may be controlled.