Engineers in a ship repair yard in Singapore and a London firm of marine consultants may have an answer to the mystery of why 10 large tankers carrying crude oil have been lost in the past year. The engineers, during a routine check discovered small cracks in the hull of a very large oil tanker and promptly informed two naval architects working for Fraser & Co. They recently completed a computer simulation of the way one 10-year old VLCC was loaded with various grades of oil. They concluded that changes in the way this ship is now used--to carry different densitites of oil rather than just one grade as was the practice 10 years ago--have caused it to be unevenly loaded, seriously weakening its structure. This conclusion is disturbing for operators and crews of other large tankers built at the same time; the Betelgeuse and the Ocean Concentration (which broke in two in Rotterdam harbour recently) were nearly identical ships of the same age. The two naval architects, David Jones and David Adam, have made known the results of their study. The most serious result was that during one "normal" loading of oil the tanker was overstressed along its length by 58 per cent for a short period. When the loading was complete, the crude instruments built into the ship indicated that everything was back to normal. No one on the ship--including the chief officer responsible for loading the different grades of oil around the seven main tanks--could possibly have had a precise idea of what was happening to the ship's structure. One way to prevent the insidious weakening of these older ships, Jones and Adams say, is to equip them with a simple and relatively cheap computer. The computer could also continuously monitor the position of the loads on board, sounding a warning when overstressing seemed imminent, and providing a "black box" record of every time the ship was loaded. Such a computer might cost about 13000 pounds sterling. No further information in article.

  • Availability:
  • Corporate Authors:

    IPC Magazine Limited

    King's Reach Tower, Stamford Street
    London SE1 9LS,   England 
  • Authors:
    • Stansell, J
  • Publication Date: 1980-7-31

Media Info

  • Pagination: p. 350
  • Serial:
    • Volume: 87
    • Issue Number: 1212
    • ISSN: 0262-4079

Subject/Index Terms

Filing Info

  • Accession Number: 00319826
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Oct 27 1980 12:00AM