This program calculates the position of a ship at sea, when two lines of possible positions are provided. The intersection of these two position lines (obtained e.g. by astronomical sextant-measurement) gives the final position-fix.
Two position lines for the ship must have been calculated before, e.g. by the program "PositionLine-V34.html", based on astronomical observation measured by a sextant. - Enter the values for the estimated latitude and longitude of the ships position (= "Dead Reckoning Position 1"). Then enter the Azimuth1 of the previously calculated direction to the celestial body, like sun or moon. Then enter the difference Δh1 between the calculated and measured distance of the DR1-position from the image-point of the celestial body. Positive value means measured position closer to the celestial body, negative further away than DR-position. If your ship has moved from point DR1, enter the course and the distance to the point where the second measurement has been performed. Then enter Azimuth2 and Δh2 observed and measured at this second point DR2. Then klick CALCULATE. The results give the position DR2, and then the actual position by latitude and longitude, the deviation from the DR2-position is given in nautical miles and angular direction. Angles are counted from North 0..360 degrees. Degrees should be entered as positive numbers for directions North and East, and as negative numbers for directions South and West. (Angular minutes can always be entered positive).
This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the license or any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License (www.gnu.org/licenses/) for more details.
If errors are encountered, kindly send a note to firstname.lastname@example.org. Author: Heiner Müller-Krumbhaar - Last update 14.dec.2022.