Abstract: The paper describes solution of the boundary problem for the system long rope with object density insignificantly greater than the density of the water and small rigidity. There is only known a point of hooking the rope on the ship and depth on which the end of the towed object is sunk. Article presents the analysis of the system described above with calculation of his forms and forces of weights, buoyancy force and lift with changeable longitudinal rope’s tension. The results of calculations show capabilities and manners steering form. But what is more important it shows how to steer with the sink of the object on the water of different depths and allows safe maneuvering of the object. Besides, employment of described method and/or similar, (see [1]), for calculating the geometry of the system towed by a maneuvering ship will give better accuracy of the executed measurement by the towed object.