Sunday, September 7, 2008

Emergency Navigation, 2nd Edition

International Marine has released a new edition of David Burch's significant book, Emergency Navigation with a new subtitle: Find Your Position and Shape Your Course at Sea Even If Your Instruments Fail. This valuable book has been out of print for a few years and it's good to see it back in print.

Burch, the author of Fundamentals of Kayak Navigation (now in its fourth edition), is founder and president of the Starpath School of Navigation, a chatty intellectual who knows more about the principles of navigation than most. In Emergency Navigation, he draws upon a wide range of sources for a wide range of navigational principles, including Polynesian and Viking methods. His description of Polynesian Star Paths is a good example of the clarity with which he writes:

"The concept of a star path comes from island navigators of the tropical Pacific. The 'path' is a sequence of stars with nearly the same declination, which means they rise at nearly the same place on the horizon throughout the tropics (the Tropics Rule). By learning the sequence for the bearing from one island to another, Polynesian navigators have, in essence, established sets of celestial sailing directions. They follow one star as it rises above the horizon until the next in the sequence appears, at which time they shift to the new star for orientation. In this way, they keep track of a particular bearing on the horizon throughout the night. The same technique can be used with setting stars. It is easy to see how indigenous star paths could evolve into finely tuned routes that account for both prevailing currents and the leeway of traditional craft. Poor choices would be removed from the lore by natural selection."

Burch doesn't confine his methods to traditional ones. The book is based on the presumption that one or more essential navigation tools are lost or malfunctioning -- your compass, your chronometer, your tables, whatever -- and he demonstrates how to use whatever is available to make up the deficiency. At one point, he shows how to use a pair of polarized sunglasses to find the sun when it's below the horizon or obscured by clouds. So while a lot of the material is based on indigenous methods, a lot of it isn't. Worthwhile for any navigator, bluewater or coastal, nonetheless.

By the way: in spite of its title, Fundamentals of Kayak Navigation is by no means a basic text -- it's quite comprehensive and as such can be somewhat intimidating and more than many kayakers need. For a simpler approach, check out Ray Killen's Simple Kayak Navigation, below.

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