bluuebunny/crossref_metadata_2025 huggingface dataset:
Air Traffic Control by Programmed Navigation
Authors: Ramsayer K.
Published: January 2010

This paper proposes that the navigation and control of all airliners should be automated from take-off to landing. Each aircraft will fly according to a prescribed flight plan, to be fulfilled in position, altitude and time within prescribed tolerances. The optimal flight plan is elaborated by a central air traffic control station and transmitted by data link to an airborne computer which monitors the navigation of the aircraft. The navigation itself is based on an integrated Inertial/DME/DME system. Separate airways are proposed for the general aviation. The paper was presented at the 19th Technical Conference of I.A.T.A., Dublin, October 1972.

The permanent growth of air traffic demands rigorous regulation. The most efficient form of regulation is the careful elaboration of a flight plan, taking into account the total air traffic in the area and the rigorous fulfilment of this flight plan. The flight plan will be elaborated at a central air traffic control station by computer, taking into account both air traffic and the meteorological conditions, especially wind. This flight plan is transferred by radio to the computer in the aircraft and comprises essentially the three-dimensional coordinates of take-off point, destination and way points as well as the corresponding times; also the precomputed values of ground speed, rate of climb and rate of descent.
Traffic in the English Channel and Dover Strait: I—Traffic Surveys
Authors: Johnson D. R.
Published: January 2010

The Dover Strait is not the most congested stretch of narrow water in the world but it is the gateway used by ships of almost every kind on passage to and from nearly all the important ports in northwest Europe, Scandinavia and the United Kingdom. While the recent increase in shipping may not continue at its present rate, the modern trend towards larger vessels and higher speeds has enhanced the hazards to navigation in narrow waters and port approaches, while the volume and nature of modern cargoes have dramatically increased the risk of widespread pollution in the event of any major snipping casualty.
II—Circumstances of Collisions and Strandings
Authors: Wheatley J. H. W.
Published: January 2010

In recent years there has been a growing concern about the continuing occurrence of casualties in the Dover Strait. The unfortunate incidents in the Varne area early in 1971 raised questions about how casualties occur and what circumstances or combinations of circumstances are most likely to lead to a collision or stranding. Information was also required as a basis for estimating the risk of a casualty occurring in the Dover Strait and for assessing the effectiveness of proposals for improving the safety of navigation.
The Distribution of Collisions in Japan and Methods of Estimating Collision Damage
Authors: Fujii Yahei , Yamanouchi Hiroyuki
Published: January 2010

The estimation of collision danger is often required by harbour authorities and others for planning fairways or for increasing the safety of navigation. Fujii1 gives an approximate formula for the probability of collision in a waterway where the density of traffic, the size distribution of ships and the average speed are known. Fujii's formula is however only applicable where the traffic has been surveyed and traffic patterns are well known. Some simple method is required for estimating collision danger, especially for harbours where traffic patterns are complicated and the information available on marine traffic engineering is comparatively small.
Navigation in the Vertical Plane
Authors: Calvert B. J.
Published: January 2010

It is generally felt that by causing aircraft to follow accurate climb and descent paths the flow of traffic in terminal areas can be improved. This paper, which was presented at a meeting of the Institute held in London on 29 November 1972, with the President, G. E. Beck, in the Chair, discusses the special constraints involved in vertical plane navigation. These arise from difficulties in the accurate measurement of position, and the limitations of aircraft response. The need to fly at differing speeds and in various configurations, while minimizing passenger discomfort and external noise, is also considered.
I—A Mariner' View
Authors: Jones K. D.
Published: January 2010

In clear-weather conditions well trained mariners experience little difficulty in dealing with multi-ship encounters in all circumstances. In restricted visibility they do not display the same confidence in manœuvring even in the open sea, and the problem is amplified as the waters narrow and the traffic density increases. The plea of the mariner would be to find an anti-collision system that would make manœuvring in fog at least as straightforward as in clear weather. To satisfy such a request it might seem that there would need to be two systems, one for fog and another for clear, but it seems probable that a system evolved to work safely in fog would also be acceptable in the less demanding conditions of clear weather; this would in time be the only system adopted.
II—Some Navigation Radar Problems
Authors: Houseley P. J.
Published: January 2010

Captain Jones has indicated that the navigator needs improved technical assistance in avoiding collisions during conditions of inadequate visibility. When the aided eye fails to distinguish the aspect of a vessel until it is much closer than the optimum distance at which a risk of collision ought to be recognized, then visibility is inadequate. For large ships a warning can be required before the distance closes to three miles, for example, whereas a visibility limited to three miles is commonly experienced. However, more guidance on this point is still needed from navigators.
Voyage Delay Decisions
Authors: Wepster A.
Published: January 2010

Reduce speed, stop engines, navigate with caution. There can be little doubt that there will be very few legal obligations that are so consistently ignored as Rule 16 of the Collision Regulations at Sea. Yet the circumstance to which Rule 16 applies, reduced visibility, is only one of the causes for reducing speed and the factors involved in the decision to accept delay may prove interesting and revealing. It is the purpose of this paper to stimulate further investigation into the subject, an investigation that will certainly require the cooperation of ship owners associations and master mariner organizations and which could well be carried out by the Marine Science Departments of such advanced educational institutions as for example University of Wales Institute of Science and Technology in Cardiff.
Errors of Some Sextant Sights with a Bubble, from the Queen Elizabeth 2
Authors: Wright Frances W.
Published: January 2010

As a passenger on the Queen Elizabeth 2 on a westward crossing of the Atlantic in late May 1972, I took sextant sights with my standard marine Plath sextant and also with the ‘bubble’ attachment for this instrument. Inspired by Francis Rogers' discussion of the development of bubble sextants, my project was to compare the accuracy of the bubble sights with that of the conventional marine sextant sights, which require the horizon.
The Leap-Second of 31 December 1972
Authors: Sadler D. H.
Published: January 2010

Details have been given in this Journal (Vol. 25, pages 3 2–42) of the new system of Coordinated Universal Time (U.T.C.) introduced on 1 January 1972. In accord with the agreed recommendations a positive leap-second was introduced at midnight on 30 June 1972 when the value of U.T.1–U.T.C. (DUT1) changed from −0s.64 to + 0s.36. However, the Bureau International de l'Heure has now announced that another positive leap-second is to be introduced at midnight on 31 December 1972, when (according to current estimates) U.T.1–U.T.C. will be about −0s.2; on 1 January 1973 DUT1 will thus be +0s.8, in excess of the maximum permitted value of of 0s.7.
The Ranee Tidal Energy Installation
Authors: Gougenheim André
Published: January 2010

An article on the French tidal energy schemes appeared four years ago in thisJournal(16, 51). One of these was planned for the estuary of the Ranee, a small coastal river that falls into the Channel between Dinard and St. Malo, the other for the extensive sea-area stretching from MontSaint-Michel to the Chausey Islands, and from Cancale to Granville. These schemes had been drawn up in the years immediately following the second world war, at a time when the power-outlook in France seemed somewhat gloomy: demand was increasing continually with no quickly available new source in sight. It was, it is true, believed that ultimately nuclear energy might well be applied in industry but the time-lag was over-estimated and, in addition, it was feared that the cost would not be competitive. Tidal energy, therefore, was hailed as a welcome solution, and it seemed no wild dream to envisage its exploitation over so wide an area as the bay of Mont-Saint-Michel.

It was this that lay behind the Chausey Islands tidal energy scheme. Hitherto, hydraulic power had been drawn only from rivers; the sea might raise unexpected problems and it would have been rash to embark on so far-reaching an enterprise without first finding the answer to all the difficulties encountered on a smaller scale. In 1950 the Ranee estuary was accordingly chosen as a pilot-scheme, on a power-producing scale of about one-fiftieth. Initial studies were immediately pushed ahead, and building started at the beginning of 1961. Progress was rapid, but so much was involved that it took five years to complete the civil engineering work and another year to finish installing the equipment. Like all great enterprises that do credit to the nation's industry and contribute to the development of its economy, the plant was officially opened by the President of the French Republic on 26 November 1966.
Why Decca Works
Authors: Powell Claud
Published: January 2010

Radio position-fixing systems employing the continuous-wave hyperbolic principle, such as the Decca Navigator and Loran C, are now used by ships and aircraft numbering tens of thousands and the theory of their operation has become part of the syllabus in many courses of instruction on navigational aids. Although accepting that these systems produce position-lines along which the difference in the distance from the user to a master and slave station is constant, and that such a line is obtained by time-difference measurement in the form of phase comparison between the two received signals, it may be asked whether this process is affected by the doppler frequency-shifts that will occur if the craft is moving with respect to the stations. Surely, the question goes, these must complicate or modify the behaviour of the system and give rise to an error unless the receiver is stationary ? It sometimes seems to come as a surprise to learn that, far from being adversely affected by it, the operation of these systems is a practical example of the phenomenon to which Prof. C. J. Doppler gave his name: they work not in spite of his ‘shift’, but because of it.
The Analysis of Marine Casualties
Authors: Foster William C.
Published: January 2010

The Coast Guard is the leading agency in the United States for analysing collision statistics and generally preventing marine casualties. In this paper, which was presented at an Institute meeting held in London on 30 November 1966, Captain William C. Foster, Chief of the Merchant Vessel Inspection Division, Office of Merchant Marine Safety of the U.S. Coast Guard in Washington, describes the manner in which accidents of all kinds are investigated. The lecture was illustrated with examples of some of the extremely detailed forms which those involved in marine casualties are required to complete and of the statistical casualty returns; these are not reproduced here.

Marine casualties and accidents, whether or not loss of life is involved, are investigated by the U.S. Coast Guard for the purpose of determining the cause of the casualty and the persons, if any, who are responsible and to obtain information for the prevention of similar casualties. The Coast Guard regulations require the owner, agent, Master, or person in charge of the vessel involved in a marine casualty to notify the nearest marine inspection officer whenever a casualty results which causes physical damage to property in excess of $1500, material damage affecting the seaworthiness or efficiency of the vessel, any stranding or grounding, any loss of life, or injury incapacitating a person for a period in excess of 72 hours. When a casualty occurs in international or foreign waters, this notice is frequently given upon the American vessel's arrival in the continental limits of the United States on forms CG-2692 (Report of Vessel Casualty or Accident) and CG-924E (Report of Personal Injury or Loss of Life).
Automated Determination of the Position of Ships by Satellites
Authors: Freiesleben H. C.
Published: January 2010

It has recently been suggested that 24-hour satellites might be used as navigational aids. To what category of position determination aids should these be assigned ? Is a satellite of this kind as it were a landmark, because, at least in theory, it remains fixed over the same point on the Earth's surface, in which case it should be classified under land-based navigation aids ? Is it a celestial body, although only one tenth as far from the Earth as the Moon ? If so, it is an astronomical navigation aid. Or is it a radio aid ? After all, its use for position determination depends on radio waves. In this paper I shall favour this last view. For automation is most feasible when an object of observation can be manipulated. This is easiest with radio aids, but it is, of course, impossible with natural stars.

At present artificial satellites have the advantage over all other radio aids of world-wide coverage.
The Cost and Value of Automation at Sea
Authors: King G. A. B.
Published: January 2010

Some degree of automation is a necessary part of commercial shipping because it can reduce labour requirements, permit some redeployment of crew and help improve ship efficiency. It has sometimes, however, been applied indiscriminately.

The ship must be considered in its entirety and navigational requirements, for example, are only a sub-system. The value of an investment in automation cannot be measured solely in terms of labour saved, since some of the cost may be recouped in improved performance, saved time, enhanced safety and widened knowledge. It is particularly difficult to place a true value upon the latter two. Training, expensive specialist maintenance and the cost of spending money have to be added to first costs.

Whilst the contribution of each sub-system and its component units can be evaluated to see whether investment is justified, a measure of automatic control in the modern ship is not only desirable but inevitable. As manufacturing techniques and scientific knowledge advance, the shipowner can also expect to be able to equip his ships with cheaper, better and more compact equipment, and this will be a further encouragement to reconsider his operational methods from time to time.
The Luminous Intensity and Range of Lights
Authors: Blaise Pierre , Pétry Paul
Published: January 2010

In this paper, M. Blaise, Chairman of a committee of the International Association of Lighthouse Authorities, and the General Secretary of the Association, M. Pétry, comment on certain changes impending in the notation of luminous intensity and the range of marine lights. They conclude that the changes will be of benefit to navigators at sea and engineers.

In November 1925 the International Hydrographic Review published a report under the title ‘Observations of Visibility Lighthouses’. Since then notable progress has been made towards a standardization of methods. Relatively recently (1966), the International Association of Lighthouse Authorities (I.A.L.A.) published a recommendation for the notation of the luminous intensity and range of lights.
The Crisis in the Increase of Tonnage
Authors: Oudet L.
Published: January 2010

The increase in the size of ships is no new phenomenon. The nineteenth century saw a greater revolution in ship-building than that which we are now witnessing. In construction, wood gave way to iron, and in propulsion steam took the place of wind. These changes were not made without provoking a conservative reaction: when Admiral Courbet, then still a young officer, prophesied the end of sail he became the target of much sarcasm. His opponents could not admit that a free source of motive power could ever be abandoned. Everything that is really important and new begins by being regarded with a mistrust that is eventually swept aside: once the possibility of doing better than before exists in fact, no obstacle can stand in its way.

The sea imposes little restriction on the size of ships. Unlike roads, sea routes are not confined within dimensions which limit the dimensions of the traffic they carry. For ships, restriction comes in at each end of the route, in ports, where the depth of water limits their draught. In consequence, we have seen the size of ships increase, during the last decades, in two specifically characteristic ways.
Navigation and Radio
Authors: Beck G. E.
Published: January 2010

The use of radio as an aid to navigation is a matter for continual discussion within the Royal Institute of Navigation, and it is the subject of fresh papers in almost every issue of our Journal. Two notable presidential addresses by the second holder of the office, Sir Robert Watson-Watt, in the early 1950s surveyed separately the air and the shipping industries and, as was proper from one so directly associated with the origins of radar, made close reference to this form of navigation aid.
Relative Navigation
Authors: Holder L. A.
Published: January 2010

Liverpool has long been a major seaport and the present centre of nautical education at the Department of Maritime Studies of Liverpool Polytechnic has developed from the Liverpool Nautical College over several decades. Most of the students have a background of experience in merchant shipping and the port industry. The courses include those for certificates of competency, the examinations being conducted by the Department of Trade and Industry. The other main courses are the B.Sc. (Honours) course in Nautical Studies, H.N.D. in Nautical Science and post-experience and special courses in radar and recent developments in ship operations. Higher degrees (M.Phil and Ph.D.) are obtainable by research and an M.Sc. course is in preparation. When qualified, the students and graduates have gone to a wide range of posts at sea and ashore in the maritime industry, the majority being actively engaged in ship operations.
Navigation in the French Merchant Navy
Authors: Hugon P.
Published: January 2010

In this paper the Secretary General of the French Institute of Navigation reviews the progress made in navigation in the Marine Marchande over the last twenty years. The article of course refers specifically to a particular fleet, but it gives a remarkably clear picture of the development of navigation in merchant shipping as a whole, at any rate in the western world. Professor Hugon is an Honorary Member and Gold Medallist of this Institute.
Ocean Science
Authors: Lighthill James
Published: January 2010

In this paper the Lucasian Professor of Applied Mathematics in the University of Cambridge studies the role of ocean science in the service of mankind, and examines the interaction between the many disciplines which make up that science. The paper, which was written in May 1972 (and a version of which was published in the Bulletin of the Institute of Mathematics and its Applications for February 1973), was presented at a conference held in Greenwich on 12–14 September 1973 to celebrate the hundredth anniversary of the Royal Naval College. (Note: the National Institute of Oceanography referred to in the text is now known as the Institute of Oceanographic Sciences.)
The Presentation of Navigational Information
Authors: Treadgold M. G. , Walters D. J.
Published: January 2010

The definition of the word ‘navigation’ has been discussed frequently in meetings of this Institute and a very flexible thing it appears to be, varying its scope to suit the lecturer. This is not really surprising however, since whatever we think of as ‘navigation’ is only part of the wider business of living. In aviation for instance, the business of ‘conducting a craft as it moves about its ways’ can legitimately include seeing that the fuel tanks are full as well as pulling back on the stick to avoid hitting the top of the hill.
Authority at Sea
Authors: Oudet L.
Published: January 2010

It took three years to gain acceptance for the provision, in crowded waters, of two parallel channels for the main traffic, each reserved for streams travelling in opposite directions. It then took another four years to obtain the corresponding marking in the Dover Strait, which served as a testing ground for the system. However, since this came into operation in 1967, there has been an amazingly rapid expansion of the organization of crowded waters. At a time when new schemes are being brought to the attention of seamen, it is important to take a close look at the authority which such regulations possess.
Visual Signals for Manœuvre at Sea
Authors: Sohnke F.
Published: January 2010

Having followed national and international shipping periodicals of the past years, one can readily observe that a signalling device installed on a vessel giving early and permanent signalling of the ship's course and manœuvre is urgently needed. In this report I will attempt to give brief information on previously known ideas, analyse them, draw conclusions and make a new proposal.
‘The Schuler Pendulum and Inertial Navigation‘
Authors: Lee J. A.
Published: January 2010

Mr. Bell and Professor Stratton have in the October Journal shed interesting light on the nature of inertial navigation as applied to navigation around a planet. It is a pity that Mr. Bell has repeated that in such inertial systems vehicle position and velocity are deduced from measurement of acceleration. This idea is certainly misleading so far as understanding error propagation in these systems is concerned, if not actually wrong.
Calvert's Manœuvres and the Collision Regulations
Authors: Clissold P. C. H.
Published: January 2010

The aim of this paper, which was presented to the last meeting of Icotas (London, 14 January), is to show how the manœuvres proposed by Calvert (Journal13, 127) and by Hollingdale (Journal14, 243) could be incorporated in the International Regulations for Preventing Collisions at Sea. Calvert's objective was, as Hollingdale points out, to establish a set of manœuvres whereby a collision situation may be converted into a ‘miss’ of specified magnitude.
Computer-controlled Path Guidance with Reference to Radio Navigation
Authors: Kundler Walter
Published: January 2010

The use of shipborne computer-controlled navigation systems has increased considerably during recent years. The expected advantages depend on the type of vessel; in cargo ships the safety aspect is predominant, whereas in research vessels the accuracy and reliability of position fixing are of primary importance.

Generally, computer-controlled navigation systems include a collision avoidance facility operating in conjunction with the radar. This basic equipment is usually extended by a position fixing system, calculating the latitude and longitude from the signals of position fixing transmitters and achieving optimum accuracy by sophisticated weighing techniques (Integrated Navigation). A further step in automation is the automatic guidance of the ship on preselected tracks.
Aircraft Characteristics and Air Traffic Systems
Authors: Attwooll V. W.
Published: January 2010

It is likely that in the future aircraft designs will be increasingly tailored to optimize the traffic system rather than the economics of the aircraft considered in isolation. In this paper Mr. Attwooll, of the Mathematics Department at the Royal Aircraft Establishment, discusses the effect on the properties of air traffic systems of the individual characteristics of aircraft. This paper (published by permission of the Ministry of Defence), which reflects Mr. Attwooll's personal views rather than any official policy, was read at a meeting of the Institute in London on 28 November 1973 with the President in the Chair.
I—North Sea Oil
Authors: Gaskell T. F.
Published: January 2010

There have been many new developments in the North Sea during the last seven years since gas was first discovered in the B.P. West Sole field. First, half a dozen other gas-fields have been found and a large quantity of methane has already been piped to Britain. Secondly, oil has been discovered in the northern part of the North Sea between Scotland and Scandinavia. One may well ask why this large source of energy was not discovered many years ago. The reasons are much the same as applied to the gas discovery; the North Sea 10 years ago was not a very good prospect from a geological point of view, and in any case the techniques of exploration and production in offshore areas were not adequate until recently, especially in a place such as the North Sea wher severe storms and tidal streams make operations difficult and hazardous.
Ship Casualties in the Baltic, Gulf of Finland and Gulf of Bothnia in 1971–2
Authors: Kostilainen Valter , Hyvärinen Maija
Published: January 2010

The problems associated with marine traffic engineering in the Baltic area are difficult to solve, and casualty statistics are extremely important as a basis for safety and anti-pollution activities. A statistical analysis has been made of the data relating to a total of 283 ship casualties in 1971–72; the results are presented and the discussion covers local and seasonal distribution, distribution by other time-dependent variables, and weather, visibility and the use of navigation equipment at the time concerned. The statistics further cover the type of ship involved, its nationality, loading condition, age, speed, and the damage arising. This paper was presented at the November meeting of a Navigation Group in Helsinki.
‘Martelli's Tables’
Authors: Black A. N.
Published: January 2010

As the hitherto anonymous reviser who prepared the current G.H.A. edition of Martelli's Tables, was interested, instructed and surprised by Captain Cotter's article in the Forum on this subject. I was surprised that he should write of them as if they were things of the past. In fact they are available off the shelf at my local chart agents, and no doubt elsewhere, so a demand presumably exists today, and they are in current use. From some of the comments which he makes, and the extract from Table 5 which he reproduces, it appears that he has not seen the current edition.
An Examination of Criticisms of Automatic Radar Plotting Systems and their Advantages in Relation to Manual and Semi-auto Systems
Authors: Harrison A.
Published: January 2010

Much of Captain Wylie's note (this Journal, 27, 111) is undoubtedly correct, particularly the part headed ‘automatic versus manual’, which restates the strong operational requirement for automatic plotting. The earlier part, however, contains some truth, some error, and shows a notable omission. A detailed analysis would take far too much space, so I will deal with three points only.
Why the Rules Need Changing
Authors: Clissold P. C. H.
Published: January 2010

The Regulations for Preventing Collisions at Sea were formulated before the invention of radar, and radar has invalidated one of the principles upon which the Rules are based. This principle is that when two vessels are in risk of collision one shall get out of the way, and the other shall stand-on (except in the cases where two vessels are meeting end-on, and where the stand-on vessel finds herself so close that collision cannot be avoided by action of the giving-way vessel alone). This assumes that if one vessel can see another she also can be seen, and this is of course likely to be the case where visual sighting is concerned. From radar observations one cannot know if the other ship has observed you, and it is unlikely that we shall know this with certainty, for radar and other aids may fail. Providing there is sufficient sea-room and not too much traffic, this drawback can usually be overcome by taking early and substantial avoiding action (as recommended in the Annex to the Rules). If one ship makes a manœuvre which cancels the avoiding action taken by the other there is still time for second thoughts; but in crowded waters there may not be so. Even when both vessels are navigated correctly, the imprecision of radar predictions may lead to dangerously close passings.
A Programme for Revision
Authors: Parmiter G. V.
Published: January 2010

On the one hand, there is the inevitable reluctance to change Rules that have stood the test of time but I think this reluctance comes mainly from the older officers in their last few years of service, who, very understandably, do not wish to have to learn new Rules and find that their instinctive and almost automatic reaction to any situation gained through years of practical experience has now all to be changed.

On the other hand there is a very strong body of opinion which feels that the old Rules, designed for quite different circumstances and unable by their basic concepts to be suitably amended to meet modern conditions, must be completely re-written—amendment to the existing Rules just will not do.
Wave Climatology
Authors: Kipper John M. , Joseph Ellis J.
Published: January 2010

In a valuable paper published in July 1960 (Journal, 13, 253) Hanssen and James described the system developed by the U.S. Hydrographic Office (now U.S. Navy Oceanographic Office) for selecting the optimum track for transoceanic crossings by applying long-range predictions of wind, waves and currents to a knowledge of how the routed vessel reacts to these variables. In the present paper the authors, both of the Marine Sciences Department of the U.S. Navy Oceanographic Office, propose a method, based on this earlier work, of using climatic charts on the North Atlantic to avoid regions of high frequency storm conditions and thus improve ship efficiency. Essentially this method is for ships not being routed by a central forecasting office. An earlier version of the paper appeared on the verso of the U.S. North Atlantic Pilot Chart for March 1969.
Pilotage or Conning Radar
Authors: Stewart J. P.
Published: January 2010

This paper describes the four main functions of radar in the Merchant Navy, expresses views on the controversial matter of mode of display and indicates possible solutions to the problem. Mention is also made of the desirability of properly engraving the relative bearing ring and the necessity of being able to take true and relative bearings at one and the same time if required.
The Metrication of Navigation
Authors: White G. J. A.
Published: January 2010

In his original paper, Turner drew attention to the proliferation of units used to measure the same dimension. Granted the decision to adopt a metric system in this country, there could be no question but that SI was the correct one to adopt. It is not precisely the same as the traditional metric system at present in use on the Continent, but it seemed likely that it would become so, and, as the British Standards Institution pointed out, one change from Imperial to SI was far more logical than a change to traditional metric, followed by a change to SI.

SI avoids all the difficulties mentioned by Turner, but, as B.S.I, state (and Turner indeed infers in his statement that ‘speed (will be measured) in kilometres/hour’), we cannot abandon the hour and the day, which SI would require to be expressed as 86·4 kiloseconds and 31·4496 megaseconds respectively. Angle, too, presents a problem. The radian is quite irreplaceable in some mathematical fields but one cannot express a right angle or a complete revolution as a rational figure in radians. Horscroft revives the metric grade of one-hundredth of a right angle, but, as he points out, this logically demands a new basis for time measurement.
The Schuler Pendulum's Fatal Flaw
Authors: Bell Frank Coffman
Published: January 2010

Schuler himself genially but clearly warned here and there in his 1923 paper that he had not proved his principle, and indicated that the general proof was not within the range of his own limitations, thus inviting his readers to be critical of what amounted to interesting suggestions cheerfully offered. Professor Stratton's commentary (Journal, 21, 507), ‘The Schuler pendulum and inertial navigation’, by its scope, clearness and authenticity, could make effectual the remark that Schuler's calculation of acceleration is not correct except in one and the same great circle and possibly a few other special cases. Schuler jumps to the conclusion that it holds for any spherical motion, thus neglecting much of kinematics. The following standard analysis uses the moving trihedral and the intrinsic equations of ordinary differential geometry. There are many other methods having their own advantages.
Right- and Left-hand Dominance in Navigation
Authors: Coombs L. F. E.
Published: January 2010

This is a survey of a subject for which there are few positive conclusions on the reasons for existing controls and control practices. The position of the operator of a vehicle or craft, the preferred side for the control or conning position and the ‘rules-of-the-road’ for land and water transport and also air transport seemed to have evolved through innate and conditioned human preferences such as ‘handedness’, through customs and traditions and, possibly to a lesser extent, by arbitrary rule making. In general, man is outwardly laterally symmetrical but has a dominant side and a preferred-hand. Within the majority of ethnic groups right-hand preferring people make up 90 per cent of a population. However, despite innate preferences about which there is inconclusive evidence and the influences of a ‘right-handed’ world imposed upon the maturing child, man can acquire through learning and training a sufficient degree of ambidexterity to operate effectively the controls of complex man/machine interfaces. As long as tools, vehicles and all other artifacts remained essentially simple to use or operate they could be controlled, governed or steered by either hand or by one hand—usually the preferred—or by both hands. However, the preferred hand with any of these combinations would ‘lead’ and would provide precision or ‘fine’ control. The introduction of writing and similar tasks requiring coordination of mind, hand and eye has always reinforced the ‘right-handed’ world. For convenience this survey is divided into three major evolutionary paths: sword, steering oar and left-hand circuit.
‘By the Mark’
Authors: Hewitt R. L.
Published: January 2010

Yachtsmen, like other mariners, are being encouraged to ‘think metric’—to become accustomed to metres in Tide Tables, Pilots and Light Lists, and to make use of the new metric charts as and when these become available. Along with these changes to books and publications we can expect the introduction of metric tide gauges, and of echo sounders calibrated not in feet or fathoms but in metres. In a few years time even those yachtsmen who normally never correct their charts, or who do not think about renewing them until they are covered with cocoa stains, will be forced to work in metres.
The Treble Bearing Problem
Authors: Cotter Charles H.
Published: January 2010

It may come as a surprise to many navigators that the interesting and valuable, although seemingly little-used, method in which three successive bearings of a single fixed mark are used to find course made good, has a history of not more than about half a century.

When two or more suitably placed marks are in sight the course made good may readily be found from a series of fixes by cross bearings, and this technique is commonly used by coastal navigators. When, however, a single mark alone is available the reliability of running fixes depends upon the accuracy of estimations of courses and distances made good in the intervals between successive bearings. A table for finding the distance of a mark from two bearings and the distance run in the interval between observations was inserted in the first edition of Raper's Practice of Navigation in which the author informs his readers that the table was constructed at the suggestion of Sir Francis Beaufort and that it first appeared in the Nautical Magazine.
‘A Prospect of Navigation’
Authors: Mabuchi Shigeaki
Published: January 2010

It is interesting to consider navigation and the problem of traffic control with the common underlying concept of randomness, though Anderson's presentation seems more oriented to thermodynamics than to information theory. But the underlying philosophy is the same: entropy never increases.

In order to decrease entropy without the help of Maxwell's demon we have to introduce work or energy, that is we measure the state of a specific object and control that state with the aid of the information gained.
Marine Traffic in the English Channel and Dover Strait
Authors: Johnson D. R. , Wheatley J. H. W.
Published: January 2010

The paper describes and reviews some of the work done by NPL over a period of twelve months in a climate of growing concern about the present and future safety of marine traffic, especially in narrow and restricted waters. The increase in number, size and speed of ships in the last decade emphasizes the need for information on the characteristics of marine traffic affecting safety of navigation, while the use of very large tankers and new types of carrier has increased the potential consequences of pollution to the environment in the event of a serious casualty. The situation in the Dover Strait is further complicated by crossing traffic and by the existence of fishing grounds.
The Distribution of Collisions in Japan and the Method of the Estimation of the Collision Danger
Authors: Fujii Yahei , Yamanouchi Hiroyuki
Published: January 2010

The distribution of ship collisions in Japan is investigated and a method for estimating the number of collisions in harbours and straits is proposed, making use of maps of collision locations and the results of traffic surveys.

There are two major sources of information on marine casualties in Japan: the Report on Marine Casualty Statistics, made by the Ministry of Transport, and Report on Casualties Requiring Rescue, made by the Maritime Safety Agency. The former is based on the compulsory reports from either ship operators or owners, and casualties to foreign vessels are not included. A bibliography of collisions in the vicinity of Japan was made by taking the original report cards, overlapping data being carefully analysed.
The Mathematical Principles of Collision Avoidance
Authors: Hollingdale S. H.
Published: January 2010

This paper is primarily concerned with principles, not with practical implementation. It is therefore reasonable to start by constructing a simplified model of the physical situation in the hope that its analysis will provide guide lines for practical action.

Consider two vessels on a collision course in the open sea. An acceptable system of manoeuvres to ensure a safe passing should satisfy the following requirements;

(i) Each vessel must make a positive contribution to the safety of the encounter.

(ii) A mariner must be able to decide on his course of action on the basis of information readily available to him, i.e. on the compass bearing of the threat, not on its true motion or aspect.

(iii) All vessels must be able to operate in accordance with the same set of rules, i.e. use a standard diagram showing the prescribed manoeuvres as a function of compass bearing only.

(iv) The same set of rules must apply whether the two vessels are in visual or in radar contact.
Traffic Separation and Routing Schemes
Authors: Wepster A.
Published: January 2010

The principles and practice of routing are well established and well known today, 12 years after the conception and 5 years after the introduction of the idea in Western European waters. It is the accelerated rate of change that makes it necessary to review the present situation and consider some permanent form of review, and plan development and improvement when necessary. The changes are technological, social, political and economic. The technological changes seem predictable, are measurable and can be caught in mathematical models, and consequently are ideally suitable for modern research techniques. The econometrist endeavours to do the same with economic changes. The much later application of mathematics to often empirical data is however bound to render results with greater variance in the answers.
Traffic Regulation and Pilotage
Authors: Rhodes C.
Published: January 2010

Queen Elizabeth I when enunciating the doctrine of freedom of the high seas said ‘…the use of the sea is common to all…’. Until very recently a more appropriate phrase might almost have been ‘a free for all’ for, except for the internationally agreed Rules for the Prevention of Collisions at Sea and the demands of safe navigation to avoid stranding, the seas were free for all to sail as and how they pleased. However, rapid advances in technological development in the last decade or so, combined with changes in transport economics and national ideologies, have brought about dramatic changes in the sea transport industry—both in the size and speed of vessels and in the nature of the cargoes they carry. Inevitably the risk and seriousness of accidents has increased proportionately and in some cases become so intolerable, both socially and economically, that the public attitude towards the traditional freedom of the sea began to change and that freedom was curtailed.
What Constitutes an Acceptable Risk at Sea?
Authors: Maybourn R.
Published: January 2010

This conference is looking at a range of issues having a bearing on the flow of traffic and the safe conduct of vessels at sea. It seems clear from many of the papers that more needs to be known of the manner in which ships react one with another and, by implication, regulation of traffic at sea can no longer be a matter within the sole competence of the experienced and dedicated mariner, as it has been in the past. If optimum safety is to be achieved, both the mathematician and the operational research expert will also have their parts to play in assessing the merits of possible solutions.
Traffic Regulation and Pilotage
Authors: Rhodes C. A.
Published: January 2010

Enunciating the doctrine of the freedom of the high seas, Queen Elizabeth said ‘… the use of the sea is common to all, neither may any title to the ocean belong to any people or private man…’. It might have been more appropriately phrased if she had said—the sea is a free-forall, because until comparatively recently the common interpretation of the freedom of the sea has been the right for all to sail as and how they please, unhindered and unrestricted except for some internationally agreed rules for preventing collision and the demands of prudent seamanship to avoid stranding. Indeed masters and owners alike considered it their unquestioned right to use the waters of their choice and, in close quarter situations, it was often the man with the strongest nerves who won the day.
A Survey of Marine Accidents with Particular Reference to Tankers
Authors: Grimes C.
Published: January 2010

The committee which looked into the scientific and technological aspects of the Torrey Canyon disaster in 1967 recommended that an assessment should be made of the probable future frequency of large-scale oil pollution along the United Kingdom coastline so that the scale of effort necessary to meet such threats could be determined. The Defence Operational Analysis Establishment of the Ministry of Defence, which has considerable experience in the collection and analysis of large amounts of data, was considered best suited to undertake such an assignment.
The Radar Detection of Dangerous Storms
Authors: Perry R. E.
Published: January 2010

Aircraft such as the Comet normally fly above cloud formations, but their approach to the airport involves a long and more or less gradual descent which may take them through adverse weather conditions. Violent thunderstorms, for example, which are fairly common in some parts of the tropics, constitute an obvious danger, and the provision at airports of an effective system of cloud warning could provide an added measure of safety along air routes.
Recent Developments in the Study of Bird Navigation
Authors: Matthews G. V. T.
Published: January 2010

Since the publication in 1951 of a paper read to the Institute on bird navigation, a number of significant advances have been made in this field and a brief review of such progress will not be out of place. Most of this recent work has been concerned with the ability of birds to home to an area previously known to them. A useful summary, in English, has been published on the experiments done in Germany on the simple, inherited, one-direction movements of young birds on their first migration. The use of the Sun as a compass, in at least many cases, appears to be well established.
The Use of Radar for Preventing Collisions at Sea
Authors: Wylie F. J.
Published: January 2010

The use of radar for preventing collisions at sea seems to have raised four main problems in applying the International Regulations for Preventing Collisions at Sea. These are: (I) In what, if any, measure radar contact covers ‘sighting’ within the meaning of Article 28; (2) whether the position of another vessel can be ascertained by radar in the precise sense intended in para. 2 of Article 16; (3) how, if at all, the use of radar should be considered to modify the ‘existing circumstances and conditions’ which, under Article 16, govern the use of moderate speed in poor visibility; (4) the application of the Steering Rules (Articles 17–27) when radar is in use.
Time Determination and Time Keeping
Authors: Jones Harold Spencer
Published: January 2010

The rotation of the Earth provides the ultimate standard of time. As the fundamental unit of time we can use either the mean solar day or the sidereal day; these two units are related in a definite manner, so that when one is determined, the other can be inferred. The purpose of any timepiece is to subdivide the day into shorter intervals, and so give the time at any instant. No timepiece will give exact time; the error of the timepiece at some definite instant and the rate of change of that error, or, briefly, the rate, must be determined in order to extrapolate for the correct time at some subsequent instant. The accuracy of the extrapolation will depend upon the uniformity of the rate of the timepiece. Radio time signals sent out from an observatory, which is responsible for the determination and distribution of time, provide the most convenient means for deriving the error and rate of a timepiece. For normal navigational purposes an accuracy of about 0·05 seconds is adequate. But for the purpose of frequency control a very much higher precision is needed—but a precision in time interval rather than in absolute time. Some of the radio-aids to navigation depend upon the accuracy in standardization of frequency, so that high accuracy in time interval has become, indirectly, a navigational requirement.
Wind Statistics and their Application to Airline Operations
Authors: Williams E. Brook
Published: January 2010

During the course of the Second World War, consideration was given to the means for operating post-war air routes. Concurrently, discussions were taking place as to the type and performance of the aircraft likely to be available. It was, however, quite obvious that, as we had had no previous experience at the higher altitudes at which these operations would be carried out, account would have to be taken of the winds which would be experienced, and steps were taken therefore to procure these data whereby to plan the routes.