This book has been written to give a comprehensive background for the understanding and use of the two radio aids and the Radio Magnetic Indicator. It is not in any way a substitute for practical training and instruction.

The important fact to be remembered is, that to make full use of instrument navigation systems, it is necessary to hold an instrument rating. An I.M.C. rating is not the same thing and, useful as it is, represents only a proportion of the training required.

The instrument descents into Guernsey and Jersey are included to give that extra depth of understanding to the basic exercises, and as an introduction to the more advanced techniques.