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NavPac and Compact Data


Digital Publication Number: DP 330

NavPac and Compact Data 2021-2025 cover The purpose of this publication is to provide navigators and astronomers with simple and efficient methods for calculating the positions of the Sun, Moon, navigational planets and stars over several years to a consistent precision with the aid of a pocket calculator, personal computer or laptop.

The software package NavPac runs on an IBM PC or compatible, and enables navigators to compute their position at sea. Its manual is included on the CD-RoM which also includes part of the Royal Navy's Admiralty Manual of Navigation (Volume 2). The package contains features additional to the book, e.g. calculating great circle and rhumb line tracks. There are also functions for calculating rise and set times of celestial objects and determining the altitude and azimuths of navigational objects.

NavPac is used world-wide by the Royal Navy (RN), other navies and by navigators who require an independent means of navigation. The RN Initial Warfare Officer (IWO) qualification is the equivalent of the Standards of Training, Certification and Watchkeeping (STCW) navigational watch certificate, and by obtaining the Ocean Navigation Certificate, which is an element of the IWO qualification, the student uses NavPac as installed on RN vessels. The tables and coefficients and the algorithm for determining position at sea from observations made with a marine sextant have been used by navigators since 1981. NavPac v4.1.1 is supplied with NavPac and Compact Data 2021-2025.

Additional astronomical data files are stored on the CD-RoM, which can be read into any personal computer. Astronomers, navigators, surveyors and general users will find these data files ideal for making astronomical calculations where positions of the Sun, Moon, planets and bright stars are required.

"NAVPAC provides astronomical data and is a fast, reliable, authoritative method of solving Spherical Great Circle, Spheroidal Rhumb Line and astro-navigation calculations ... NAVPAC is in Royal Navy service and is the Royal Navy's preferred method for obtaining astronomical data and solving the above calculations".

Para.201, BR45(1) — Admiralty Manual of Navigation, Volume 1 (10th edition).



You can purchase your copy from Admiralty Paper Distributors.


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Last modified: Wednesday, 31 March 2021 at 03:49:28 BST