In order to obtain the fundamental data concerning the method of fixing the ship's position during its coastal sailing, the authors measured the errors of the radar bearing (EB) and the radar distance (ED), in a range of less than 12 nautical miles (NM). Furthermore, the accuracy of the radar fixes was evaluated by comparison with the cross bearing fixes. Through the EB distributed within±1°, most of them were maldistributed on the minus side and the mean values of the ED were negative in all ranges. We estimate that the main cause for these tendencies was that some errors were included in the Gyro Compass and also in the personal equations when matching the range marker or cursor line with the target and reading the dial gage. The standard deviations of the EB and the ED were 0.56 degree and 0.023 NM respectively, and the radar fixes showed higher accuracy than the cross bearing fixes in most ranges.
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