NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Brad Morris
Date: 2016 Apr 11, 21:25 -0400
Jerry
The Kriegsmarine navigated using the MHR-1 (and sometimes the MHR-2). The slide rule is accurate and very fast to use.
In fact, printed on the MHR-1 is an admonition to use the F-Taffel, but only when the singularities of the rule are approached.
If you want to read more about the slide rule, NavList is virtually choked with information about it (and it's British predecessor, the Bygrave slide rule).
So you need not worry that the navigator used a lot of scrap paper. It's likely that the navigator rarely pulled the F-Taffel off of the shelf. That is, given the speed and accuracy of the MHR-1.
Brad
Hi Paul, I read your analysis with interest. Thank you very much for sharing it. I can see how that the corrections for time and latitude can be a source of error. In my opinion, the biggest drawback to the use of the F-Tafle (compared to the similar H.O. 208) is the frequent and sometimes tricky interpolation that is required. As a beginner, I am uncomfortable with estimating and so take up a lot of time doing the interpolation mathematically. With the corrections for time and latitude sometimes a double interpolation is required. The U-boat navigator must have gone through a lot of scrap paper and graph paper. The 1941 Nautical Almanac also requires considerable interpolation. I guess it was a way of making the tables as compact as possible. It certainly makes one appreciate the modern Almanac and inspection table sight reduction tables like H.O. 229/249. Jerry
