In 1947 it was felt by the Ministry of Transport that although the radar to be installed by the Mersey Docks and Harbour Board at Liverpool would demonstrate the suitability of this type of equipment in meeting the requirements of the larger ports, it was probably beyond the resources of many small ports and indeed was too elaborate for their needs. It was therefore decided that the Ministry's Operational Research Group should survey representative small ports in the United Kingdom in order to estimate the advantages that could be expected if shore radar were to be fitted and to discover what limitations there were likely to be in such fittings. As a sequel to this inquiry, it was proposed to select one port as the site for a trial, to be sponsored by the Ministry, in which a simple radar installation would be employed. The vital importance of having direct radio communication between ship and radar station was fully recognized from the start, and it was assumed throughout the investigation that this facility would be ancillary to the radar, the pilots probably carrying portable transmitter-receivers.
The need for investigations into the detection of ice by radar became apparent when merchant ships started reporting that ice formations were inconsistent radar targets, and that ships relying upon radar to navigate through ice areas could, in some circumstances, have their safety endangered.Certain investigations, notably those carried out by the U.S. Coast-guard Service and by the Swedish Defence Research Institute, resulted in the publication of a great deal of useful descriptive information but it was not accompanied by measurements of the actual echoing power of ice targets. With the object of carrying the matter further, a special enquiry was made during the 1950 and 1951 North Atlantic ice seasons, when a number of British ships plying North Atlantic routes completed questionnaires in which the sizes and shapes of ice formations were noted together with their radar detection ranges. This enquiry was instituted by the Operational Research Group in the Marine (Navigational Aids) Division of the British Ministry of Transport, which later analysed the data collected and issued a report. There were, however, certain limitations in this investigation. For example, the performance of the radars was not known, because of their inherent differences and the fact that none of the ships carried instruments, such as echo-boxes, for checking performance; further, propagation conditions at the time of making the observations were not established.
In present designs of radar sets for merchant ships, the radar-equipped ship is represented as being at the centre of its own P.P.I. picture. But there is a case for having an off-centre display. In this article are discussed possible advantages to be obtained from such a display, when the set is being used for collision warning away from a coast-line. The author recognizes that some of the opinions expressed are of a controversial nature.
The view is taken in this paper that an automatic navigation system should be capable of weighing up data and issuing instructions, in the same manner as a human navigator. Conventional information tends to offer static rather than dynamic data.It is suggested that there are several stages of development towards completely automatic navigation: (i) a dynamic interpretation of the existing navigational situation, (ii) the automatic prediction of future situations, (iii) automatic navigational advice, (iv) automatic control of a ship under the supervision of a navigator. Such control would not take care of all situations but would be particularly suited to some; a list of the information likely to be required for presentation is given.For entirely automatic navigation to be feasible, the whole of the process of transport at sea may have to be reviewed. It is suggested that the trend should be towards presenting error, rate of change and forecast data.
Radar Observer's Handbook for Merchant Navy Officers. W. Burger. Cloth 8-£ x 6 in., i£g pp., illustrated. Brown, Son & Ferguson, 1957, 16s. This is essentially a practical book for the practical seaman. Except for the introductory chapters, almost every sentence contains information which can be put to use either in the manipulation of the radar set or the navigation of the ship. To achieve this, theory has been curtailed and philosophy virtually exiled; the result is a compact book probably comprising the elements of what is required to use radar in a ship, and incidentally to pass the Ministry of Transport radar observer examinations. In general the book follows the arrangement, if not the style, of the Institute's Use of Radar at Sea. Chapter headings include Fundamental Principles, Nontechnical Description of a Radar Set, Interpretation of Display, Use of Radar for Navigation, Plotting and Use of Radar for Anti-Collision. It is up to date in that the true-motion display is described. A number of radar plotting problems (with answers) are appended, and there are some revision questions. The book is brightly written, and the chapters on display interpretation show that the author is not insensitive to the intrinsic fascination of the radar panorama. He has insight and an apt turn of phrase, for example: 'What then makes a set popular with a sailor? The answer is that sets which require little maintenance and need little or no repairs are said to be ' 'popular ". ' 'Echoes of steel ships and most buoys possess a greater amount of reserve brilliance than the sea-clutter. .. " Perhaps the author sometimes allows his aptitude for a transferred epithet to lead to ambiguity, as in his statement that 'The nearer a vessel comes to the coast, the better radar will become as a navigational aid. Its accuracy will increase rapidly.' But of course the radar set itself suffers no such sea-change; it is only the position fix afforded by it which improves in accuracy as reference marks are approached. The line drawings accompanying the text are rather unpolished and in some cases, even if allowance is made for the absence of professional finish, they are insufficiently close to the truth; for example Fig. 9 (pulse shape) and Fig. 45 (obscuring effect of a mast). Also, since the degree of confidence placed in a technical book may often be estimated by the attention to minor details, the publishers would be advised to see that gaffes such as the abbreviation ' c m. ' for centimetre are corrected in future editions. However, these small criticisms should not be allowed to obscure the fact that the author seems to have a good grasp of the principles generally conceded to be correct. This applies not only to the more factual fields but also to the subject that is most controversial of all, as well as being the most crucial, that of collision avoidance. In one of his rarely permitted excursions into philosophy, Captain Burger sums up his attitude as follows: 'The great advantage of radar lies in the fact that for anti-collision purp...
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