Find your position at sea with no previous celestial navigation experience.
GPS Backup with a Mark 3 Sextant
By David Burch
$19.95 ...item# 1997
No power, and batteries used up? This book and an inexpensive Mark 3 sextant lets you carry on. Alternatively, if you want to learn a basic celestial navigation position fix for any reason with minimum investment, this book shows how to do that.
It is a short book; mostly tables. You can read it in an hour or two, master the sights in less than that, and find your position the next time you see the noonday sun.
Our guiding principle for this booklet was to provide a means of learning and executing a position fix at sea when a vessel has lost its GPS navigation. We wanted a solution that is compact and inexpensive, using tables and procedures that are easy to learn and use. This goal led to our proposing a minimum kit that mariners would not hesitate to add to their gear to cover the unlikely situation it would actually be needed. Mariners who cross oceans in small boats realize they must be self-reliant and cover all contingencies.
For mariners who do not have the opportunity to learn the full range of celestial navigation, this booklet and a Mark 3 sextant serve as an inexpensive backup that can be used to navigate across any ocean.
The almanac pages included have been custom designed to facilitate fast, easy solutions for Lat and Lon from the sun, plus we include a unique new Regiment of the North Star for easy Latitude by Polaris sights on any date.
Needless to say, as a marine navigation school dedicated to promoting safe navigation practice and prudent seamanship, we recommend learning the full range of celestial navigation, which includes much more than just finding your Lat and Lon once a day by the sun. But we, as a practical training resource, face the reality that an increasing number of mariners intend to count on the GPS, along with backup GPS and batteries. If that is the case, may we recommend you have a look at our economical GPS backup kit. It can be thought of as a deep backup, or just something fun to do underway.