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Contents

1959: Vol. XXXVI, No. 1

The Decca System for Ship Acceptance Trials

Submitted
July 26, 2018
Published
2018-04-11

Abstract

This newsletter describes the Decca procedure used nowadays in the Netherlands for conducting ship acceptance trials, such as speed, turning circle, etc... Results of some of the trials are given and a worked-out example is added as an appendix. For speed trials carried out during daylight, the accuracy (standard error) is of the order of 0.1 to 0.2 % of the hourly speed. A few night trials resulted in an accuracy of 0.4 %, but the possibility of a slightly larger inaccuracy during night trials cannot be excluded. A graph of the relation between speed, depth of water and ship’s draft is given in section 2. In section 12 the results are given of simultaneous determinations of speed on the measured mile and by means of Decca; the difference in speed from the two methods is 0.25 % only. Section 14 summarizes the advantages of the Decca method. For speed trials on the measured mile, reference is made to newsletter no. 28, 1958 (*).