Published online by Cambridge University Press: 23 August 2006
K. H. Zevering has recently proposed a way to calculate the position of a moving observer, from the intersection of position circles, that differs from the methods hitherto accepted by mariners1. Zevering concludes, from discrepancies between his own results and that of other methods, that those others are in error. However, the discrepancies result from incorrect assumptions in his proposed method, which give rise to erroneous answers. My comments will be restricted to the simplest case of two observations only, and will assume that the Earth is, for our purposes, spherical.
1 Zevering, K. H., (2006). Dependability of Position Solutions in Celestial Sight-Run-Sight Cases – Part 1., The Journal of Navigation, 59, 155–166.CrossRefGoogle Scholar
2 In European Journal of Navigation, (2003) “The K-Z Position Solution for the Double Sight”. 1, 3, 43–46. That paper was rendered unintelligible by a combination of mistakes, both typographical errors and author's errors. Typographical errors were noted in a later issue, vol.2 no.2, but not the substantial errors made by the author. Although he has acknowledged some of those errors elsewhere, (in “The Navigator's Newsletter”, issue 84) they remain uncorrected in EJN.
3 In “The Navigator's Newsletter”, issue 81 (fall 2003) and subsequently in issues 82, 84, 85, 86, 87 and 88.
4 “The Navigator's Newsletter”, issues 83 and 87.