A shipboard navigation system which allows vessels to be manoeuvred with great precision in hazardous waters by actually superimposing nautical chart data over raw radar and anti-collision data has been proved in its first at-sea test in the narrow approaches to Valdez harbour in Alaska. The integrated Sperry Navigation system was used on board a 75,000 dwt tanker negotiating Prince William Sound to the ice-free port of Valdez where Alaskan oil is pumped from the southern terminus of the trans-Alaska pipeline. The company says that the system allowed accurate navigation to within 100-200 feet during critical manoeuvres through the narrow straits. Sperry's CAS/Channel Navigation Module used a computer generated "map" on magnetic tape of Valdez harbour and its navigation marks and shoals based on chart data and experienced marine personnel familiar with the harbour. The system was developed by Sperry specificially for operations involving navigation on narrow approaches. Because the data is displayed on the collision avoidance system's plan position indicator, navigation and collision avoidance are conducted simultaneously from one coning station. Data concerning a wide variety of navigational hazards can be added to the magnetic tape to re-create on the CAS screen all relevant information needed for safe navigation. The CAS plan position indicator assumes the characteristics of a relative motion "chart", enabling blind pilotage to be carried out without reference to the large number of sensors normally required. The integrated navigation system uses a central computer to process navigational data from several sources such as satellites, Loran and Decca to provide an optimum estimate of the ship's position.

  • Availability:
  • Corporate Authors:

    Seatrade Publications Limited

    Fairfax House
    Colchester CO1 1RJ, Essex,   England 
  • Publication Date: 1978-11

Media Info

  • Pagination: p. 73
  • Serial:
    • Seatrade
    • Volume: 8
    • Issue Number: 8
    • Publisher: Seatrade Publications, Limited
    • ISSN: 0037-0428

Subject/Index Terms

Filing Info

  • Accession Number: 00180413
  • Record Type: Publication
  • Source Agency: Seatrade Publications Limited
  • Files: TRIS
  • Created Date: Sep 27 1978 12:00AM