Abstract :
The paper indicates the progress in development and usage of long-range radio aids to navigation in the last decade, and is almost exclusively concerned with air navigation. Some indication is given of the changing operational requirements, and of the extent to which the choice of future aids is likely to be affected by them and by economic and international considerations. The main features and anticipated performance of new aids are summarized, and particular reference is made to aids which are in an advanced state of development but have not been the subject of papers presented to The Institution. The conclusions reached are that for at least 10 years considerable use will be made of self-contained aids, utilizing Doppler or inertia principles, particularly for air navigation. Ground-based systems will still need to be used to complement the self-contained aids, and for marine purposes where justified. Economic considerations, however, are likely to limit the deployment of the more expensive ground-based systems to those regions or routes where particular problems of congestion or navigation arise, and these considerations will doubtless govern the final choice of such an aid.
