Navigation aids

Compasses are the most useful and commonly used navigation aid. Other methods of finding direction, such as use of the sun, the stars and the moon are helpful at times, and more details on such methods are in Gatty (1977 p. 218–233) and Phillips, Phillips and Foley (1989 p. 91–104). As computer technology enters the realm of navigation, smaller and more accurate navigation aids, such as the Global Positioning System are available (see Chapter 31). Altimeters are also of value in certain circumstances.