The paper addresses long-term losses due to hull and propeller degradation, short-term involuntary dynamic losses due to weather factors, ship motion and steering, and losses resulting from ballasting/loading practices. By hull degradation is meant the unavoidable mechanical, chemical and biological deterioration of the hull; by propeller degradation is meant propeller blade roughness. It does not address losses due to propulsion plant degradation, but shows that losses resulting from the latter effect are separable from those under discussion by the performance monitoring techniques described. Performance monitoring of the total system is achievable by an extension of the approach presented to include the propulsion plant relationships. Alternatively, it can be achieved by incorporation of existing plant performance techniques such as described by Attwood into the speed performance monitoring system described. The paper does not address voluntary speed losses in rough weather resulting from a reduction of power ordered by the ship's master to avoid intolerable levels of certain aspects of ship behavior in weather. Such losses are dependent on the subjective judgment of the captain and are difficult to estimate. Measures and criteria for these losses have been addressed by Lloyd and Andrew and are not considered further in this paper.

  • Supplemental Notes:
    • Shipboard Energy Conservation '80, presented by the New York Metropolitan Section of SNAME, New York, New York, September 22-23, 1980.
  • Corporate Authors:

    Society of Naval Architects and Marine Engineers

    601 Pavonia Avenue
    Jersey City, NJ  United States  07306-2907
  • Authors:
    • Logan, K P
    • Reid, R E
    • Williams, V E
  • Publication Date: 1980

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00322765
  • Record Type: Publication
  • Report/Paper Numbers: Session 1-B
  • Files: TRIS
  • Created Date: Nov 29 1980 12:00AM