Abstract: Charles H. Smiley (1) states that the interpolated value of the Greenwich Hour Angle of teh sun, by the Nautical Alamac, is subject to significant error. The error derives from the fact that the interpolation tables for the two-hour interval between tabular values of GHA are all computed on the assumption that the hour angle of the apparent sun increases at the uniform rate of 30o per two-hour interval. The actual range of this increase is from 29o 59.3 to 30o 00.5'. The maximum possible error is 0.7'. Smiley has discovered that teh average of all errors, taking into account all times of day and all days of the year is 0.14'. Therefore, the errors are inconsistent with a precision of 0.1' in tabular values, and the maximum errors are inconsistent with the accuracy of observation attainable in surface navigation.
Published in: NAVIGATION, Journal of the Institute of Navigation, Volume 1, Number 4
Pages: 87 - 94
Cite this article: -,, "TECHNICAL NOTES AND COMMENTS", NAVIGATION, Journal of The Institute of Navigation, Vol. 1, No. 4, 1946-1947, pp. 87-94.
Full Paper: ION Members/Non-Members: 1 Download Credit
Sign In