In this paper, which was presented at an Institute meeting, held in Britannic House in London on 1 December 1970, the Chief Marine Superintendent of the BP Tanker Company examines the problems of operating large merchant vessels in the Arctic and describes the experience gained from the two voyages of S.S. Manhattan through the North-West Passage. The chair was taken by the President, Rear Admiral G. S. Ritchie, C.B., D.S.C, Hydrographer of the Navy.

It seems likely that the S.S. Andrea Doria of Genoa still lies on the shelf south of Nantucket Island's shoals, resting on her damaged starboard side with her port side only 23 fm. deep under position 40°29′.4 North, 69°50′.5 West; and that 2 miles to the north-west are to be found some-how fixed on the same bottom the two 700 ft bower chains, their windlass, and a large piece of the crushed bows, all detached from the M.S. Stockholm—but not her anchors. The U.S. Coast Guard Cutter Evergreen reported from the scene at the time the sinking of Doria as of 261409Z on the calm summer mid-morning of Thursday, 26 July 1956, New York civil time. A few minutes thereafter Stockholm, having after hours of effort finally cut her bower chains, left the empty scene at low speed and with escort bound for drydock in Brooklyn, her anchors firmly formed into the remains of her bows. Although full power was available and used, she had not been able to move from this unconventional but all too effective anchorage since about 11:09 by her bridge clock the night before when she had come from 18 kt. to a dead stop in something like 2 sec. of time. During the pleasantly warm and moonlit night, of the more than 2000 persons on the scene only a few, mainly those who had actually seen the event with their own eyes and lived on, knew that two ships had been in collision. No one in either ship had expected anything uncommon, at most a routine passing clear of another and unknown ship, until the last minute, and even then only two or three believed collision could, let alone had, come to pass.

In this paper, which was presented at the Quadripartite Meeting of the Institutes of Navigation in Rome, 11–14. May 1970, the author describes the precise acoustic navigation systems designed for use with submersible vehicles as distinct from typical cruising submarines. With recent technical advances in position finding a whole new range of underwater tasks for the submersible has been opened up.

Captain Dickens, an Elder Brother of Trinity House, here describes the history and function of the lighthouse authorities in catering for the needs of shipping around our coasts, and discusses the wide range of navigational aids now in use. The paper was presented at an Ordinary Meeting of the Institute held in London on 18 November 1970 with the President, Rear Admiral G. S. Ritchie, C.B., D.S.C., in the chair.

One of the first lights to be set up to aid mariners was the Pharos erected at the entrance to the port of Alexandria in 270 B.C. and said to have been visible at sea for 40 miles. With the development of maritime traffic, more and more lights have been established so that shipping can proceed in comparative safety around the various seaboards of the world. In the United Kingdom the early lights and beacons were either privately owned, attached to various monasteries or managed by the Trinity Houses, which were corporations of seafaring men.

This paper looks at the cost of navigation and endeavours to establish a relationship, of the type studied by Professor H. Benford, between manning and its associated cost in British shipping. Certain assumptions are made concerning the capital investment and operating costs for navigation equipment and from these the progressive savings are estimated for minimum manning and an unmanned bridge. Captain McKenzie is Managing Director of Marine and General Computer Consultancy (I.O.M.) Ltd.

After some considerable investigation into the costs of marine equipment and accommodation it has been found that there is the greatest difficulty in establishing a base cost on which to examine possible reductions. Equipment, salaries, accommodation and fringe benefits vary so much from company to company and ship to ship that any comparison is meaningless. Thus we must consider some hypothetical ‘standard ship’ and define fairly closely what equipment is already on board and the average salary for staff or crew members. It seems reasonable to look at a modern ship equipped with all the devices which an up-to-date shipowner considers necessary for her operation and—more important—her safety.

The Collision Regulations were long considered as sacrosanct and the question posed by this paper never arose. How to prevent collisions? Simply by applying the Regulations established for that purpose. Nevertheless a revision of the Regulations has been decided upon, to be undertaken by an international conference to be convened in 1972, and meanwhile many public and private bodies have applied themselves to the preliminary studies. As the author is not familiar with all the work now being done in this way a general review will not be attempted, but some thoughts on the subject arise from Commandant Robichon's paper ‘Reflections sur une enqu^tersquo; in the January 1970 issue of the Journal de la Marine Marchande and from the proceedings of the Working Party set up in the spring of 1970 by the Institute of Navigation, of which the author was a member.

Judging from what is written in early Sailing Directions and navigation manuals it would appear that seamen of North-west Europe laid great store in their knowledge of the nature of the bottom in the seas in which they traded. And indeed, even at the present time, mariners are provided (although they may seldom use it) with fairly detailed information about the sea-bed, designedly to assist them in pilotage. A navigator may read, for example, that:

‘The bottom in the Western Approaches appears to consist, mainly of fine or coarse sand, a great deal of broken shell, occasional patches of pebble, gravel, small stones, and, now and then, mud. The sand is mostly white, but in numerous places yellow sand and also black specks are met with…. The greater proportion of yellow sand is found to lie southwards of 49°30′ N and the far larger portion of black specks northwards of that line. This peculiarity is so marked, especially between 9°40′ and 7°30′ W that the mariner running eastwards, and supposing his vessel to be to the southwards of this parallel, should certainly suspect his having been set northwards of his reckoning if the soundings disclose this mixture of black specks to any great extent and with any frequency.’

In the design and analysis of air traffic control systems the considerations which lead to the adoption of a particular route and control structure in a given airspace are partially governed by the traffic demands between given points within the area concerned. When air traffic control plans are being developed for use in a particular area, it is of prime importance to know where the main A.T.C. problems lie and to concentrate planning effort in these parts of the system. The development of routing and control procedures should take into account the degree of risk associated with any particular route structure. In the case of near mid-air collisions (NMAC's) or collisions, quantitative prediction of the risk involved is difficult. In this paper a simple theoretical method for predicting the number of NMAC's for a particular route structure is given. Such a method has been used practically for determining the amount of control required for a particular off-airways area and to help determine the optimum control procedures for air traffic planning in that area.

In this paper the basic principles of avoidance action are developed. It is shown that a unique set of rules exists which will guarantee the safe passage of converging aircraft; when two are involved, if either, or both simultaneously, act according to these rules, it is impossible to have an accident whatever the situation. (This assumes inerrant assessments on the part of Controllers, and it also assumes that the uncontrolled aircraft continues on course.) The rules are consistent with the Rules of the Air. Past attempts to formulate rules are compared.

The action taken by an aircraft in flight to avoid coming dangerously close to some other nearby aircraft we call ‘avoidance action’. This action may be made by the pilot should the other aircraft come within his field of view, or if ground controlled, it will be initiated by the Radar Controller. The pilot works to the Rules of the Air and the Radar Controller works to them whenever it is possible for him to do so. The Rules of the Air do not always help the Radar Controller because, in every case, except for two aircraft approaching each other head-on, one or other has the right-of-way and ‘an aircraft which has the right-of-way shall maintain its course and speed.’ This means that an aircraft which has the right-of-way must not take avoiding action. The object of this paper, therefore, is to attempt to propose a set of avoidance action rules which will assist Radar Controllers in their task.

In this paper, which was originally published in Navigation, Paris, July 1970, the distinguished General Secretary of the French Institute of Navigation, Professor Pierre Hugon, a Gold Medallist of this Institute, examines some of the premises adopted by M. W. Richey in his paper on the Institutes of Navigation presented to the Australian Institute of Navigation in October 1969 (this Journal, 23, 99). It is interesting to note the extent to which the conclusions in these two papers differ in emphasis.

Following in the footsteps of my friend Mr. M. W. Richey who, at the twentieth anniversary meeting of the Australian Institute of Navigation in Sydney on 10 October 1969, presented a remarkable address on ‘The Institutes of Navigation in the 70's’, I am impelled to state the position of the sister Institute in France by examining once again the very principles of such an undertaking and discussing its future character. This unpremeditated essay concerns a duty and a faith which, though they must not give way to doubt, are nevertheless open to question.

The recent collisions in the English Channel and the Dover Strait have caused a great deal of public disquiet in this country and the United Kingdom's Department of Trade and Industry's Safety of Navigation Committee were invited to discuss what, if any, measures should be recommended to Imco to improve the routing system in the Strait. The Institute of Navigation, with its French and German counterparts, was largely responsible for the introduction of the routing scheme in force in the Strait and has since its introduction in 1967, by means of a series of international working groups, kept a watchful eye on how things were going, and on occasions made recommendations for its improvement.

In the October Journal, p. 538 and Table I on p. 539, it is shown that the number of collisions per fog day (abbreviated below to c/fd) has fallen by some 20 per cent since routing was introduced in 1967. It is not legitimate to assume without further argument that this is a case of cause and effect.

As a serving ship-master I have made many voyages in an 18,000-ton deadweight tanker (and an occasional trip in 50,000 tons) through the Dover Strait to Continental and U.K. ports. I should like to supplement Commandant L. Oudet's article on the ‘Reversal of the Traffic Flow in the Dover Strait” with a few comments from my own experience.

On page 533 of the October 1970 issue of the Journal (23, 4), the following passage appears:

‘At a recent meeting of the Safety of Navigation Committee of the Board of Trade, those present were advised by the Mercantile Marine Service Association that they had independently circulated a simple form of the present plan and the proposed reversal of routing to some 2300 Masters of their Association. Of the 500 replies received at that time, two-thirds supported the plan for reversal’

We have not yet heard the full story of the Pacific Glory—Allegro collision and it may be jumping the gun to make any comment, but one thing seems to be clear about the handling of very large single-screw ships. Because of their unwieldiness an avoiding action must be initiated while still at a considerable distance from the threat, if it is to have any effect. This distance is beyond that at which the eye of a navigator can accurately assess the risk of collision or the need to manœuvre. He must, therefore, depend upon instrumental information for making his decisions; in other words, in clear weather as in thick, he must use his radar and plot continuously if he is not to hazard his ship. If the argument is put forward that this will require two men on watch together and that the state of manning does not permit this to be done, the answer is that a change in organization must be made to make it possible.

The two following incidents might be of interest as an example of situations which arise today, and which well illustrate the standard of seamanship and watchkeeping which are encountered.

Mr. Anneveld's paper (24, 50) would have us believe that the effects of coriolis force on a ship may become appreciable as ship size increases. It is true that the drift angle does increase as the ship's size increases, because the coriolis force given by equation (1) increases as (length)3·5 and the resistive forces increase as (length)3 (on the assumption of geometrically similar ships and Froude scaling). However there is a fundamental flaw in his argument because equation (2) only applies to a vessel with zero forward speed. Moreover the effect of coriolis drift will also be to induce a yaw angle on the ship (because the centre of pressure is forward of the centre of gravity, where the coriolis force may be assumed to act) and this will automatically cause the helmsman or autopilot to apply starboard rudder in the northern hemisphere. This will immediately produce a force on the ship in the port direction, i.e. opposing coriolis force.