A bundle is a large, pre-fabricated pipe enclosing multiple other pipes and cables of lesser diameter. Ultimately installed on the seabed, these bundles are assembled on land and can range over 7 kilometers in length. When launched, the entire bundle is towed out to the parking location somewhere offshore using tugs deployed on both sides of the bundle. During the tow-out, the bundle is completely submerged, floating a few meters below the sea surface. To mitigate sagging of any portion of the lengthy bundle, it is necessary to make the bundle buoyant over its entire length.
For such a long and expensive item, a towing route is pre-planned. To ensure success, close monitoring of the horizontal positioning, bundle shape and bundle depth during the tow-out operation is a key factor. Position, course and speed of all attending vessels are also of paramount importance of maintaining the shape of the bundle and keeping it on the planned route.
Bundle tracking is accomplished using multiple acoustic beacons attached at intervals along the entire
length of the bundle. Using USBL techniques, the position and depth of each beacon is calculated in QINSy. Shaping algorithms model the bundle between these known beacon positions so that the position and depth of the entire bundle is calculated in QINSy. Position, course and speed of attending vessels is transmitted to QINSy through telemetry.
Visualization of the horizontal position of the bundle and attending vessels is provided by the Navigation Display against a background of electronic charts, satellite imagery and/or DXF drawings.