bluuebunny/crossref_metadata_2025 huggingface dataset:
Collisions in Western European Rivers
Authors: Horka Archie
Published: January 2010

Captain A. Wepster's able and professional analysis of this subject, contained in the January issue of theJournal, confirms what many seamen have long known. That these rivers—the Schelde, the New Waterweg, the Weser and, finally, the teeming Elbe, from Brunsbuttel seaward—are the world's most difficult and demanding stretches of navigation for seamen and pilots. The Captain's excellent treatment focuses attention on this and in his final paragraph he offers several considerations which, if followed, could reduce the number of collisions.

I refer to page 29; ‘Improving River and Port Authority Organizationsand, if necessary, traffic control. On page 17, with reference to changing pilots in Flushing Roads in the Schelde; who has not, when proceeding outbound, ‘overshot’ the mark when approaching the pilot ground off the Commercial Harbour ? There follows the business of making a complete circle midst moving traffic as an apologetic pilot comes a puffing to the bridge, showering abuse on the man he relieved because 'he failed to slow down in time’.

I would add a specific recommendation to those offered by Captain Wepster: For vessels outbound from the Schelde, to disembark their pilots and take on Oostgat or Wandelaar pilots at a point approximately three miles upriver, say at Sloehaven. A pilot station could be maintained at that point in the manner of the present pilot office at the Flushing Mole.
‘Radar and Rule of the Road’
Authors: Swallow G. , Kemp J. F. , Clissold P. C. H.
Published: January 2010

The amendments and additions to the existing (1960) Regulations for Preventing Collisions at Sea which were offered in theJournal,20, 103, by Captain Burger and Captain Corbet have been studied with interest. While clearly we have the same objectives at heart it will be seen from the comments that follow that the proposals are virtually unacceptable.

Rule 16 (b)

It is felt that the proposed re-wording is inappropriate as the words ‘hearing, apparently forward of her beam’ and ‘the position of which is not fully ascertained by sighting’ do not make sense in one sentence. Moreover, the proposed addition of the word ‘particular’ before ‘caution’ is not likely to deter the delinquent any further than the original wording.

It is agreed that the present wording of Rule 16 (b) may leave something to be desired in the interpretation which can be put on ‘ascertainment of position’; this has in fact been evident by some of the different interpretations which have been given by the Courts.

In the Nippon Yusen Kaishav.China Navigation Co. case of the pre-war era (1935), Lord MacMillan said, ‘In order that the position of a vessel may be ascertained by another vessel within the meaning of the Regulation she must be known by that other vessel to be in such a position that both vessels can safely proceed without risk of collision’.
A Mariner's ‘equinoctial dial’ of 1634?
Authors: Taylor Gordon E.
Published: January 2010

Recently the author was asked to suggest how an old (Scottish?) sun-dial, inscribed on a slate slab about 50 cm across and 3 cm thick, could be put into working order and set up correctly to tell the time. Upon examination the dial was found to be of considerable historic interest. Although it was quite a well-known type of dial—an equatorial—the furniture and inscriptions suggested a definite connection with the sea. Moreover, no other identical instrument is known to exist; possibly the publication of this note may help to bring other specimens to light. For this reason it is felt that a description of the various features of this multi-purpose dial will be of some interest.

Both surfaces of the dial are shown in the accompanying photographs. For clarity, a fine talcum powder was sprinkled on the dial to fill all the incised markings which would otherwise be invisible. Unfortunately the gnomon is missing. This gnomon would have passed vertically through the dial extending on either side for not less than 10 cm. Probably two circular discs with pointers were mounted centrally on the upper surface, with one of these discs bearing an arm with the ‘dioptera’, but unfortunately these items are also missing. The discs would have been capable of rotating around the gnomon. It would appear that some modifications became necessary after its construction as the four holes around the inner circle have spoilt the lettering.
A Radar Display for Collision Avoidance
Authors: Wikkenhauser G.
Published: January 2010

In the October issue of theJournal(19, 529), Commander Clissold puts forward a type of radar display which might be useful for collision avoidance, as it intends to show the aspect of the ship representing the danger. To achieve this a long afterglow screen would be used and the display would be oriented head-up, i.e. ship's head at the top of the picture to correspond as closely as possible with a possible visible situation. An electronic cursor, bearing line, would indicate a danger of collision if on constant bearing. This type of display is said to show tracks true relative to own ship's course.

Apart from the fact that 30 seconds afterglow, decaying exponentially as an excited phosphor screen would, might be too short for showing up tracks efficiently, there are some other difficulties as well with such a display. Obviously aspects of target ship would not be shown but implied only by the afterglow track. Furthermore, a display of this kind would be a true-motion type display not necessarily north stabilized but nevertheless showing all motion of other ships in true, if own ship's speed is compensated for in displacing the origin of the radial scan. The difficulty will arise if own ship changes heading and unless this heading change is also compensated for, like in a north-up stabilized true-motion display, smearing of all echoes will occur. A heading change of own ship, therefore, will produce additional apparent tracks of other ships and the apparent displacement of fixed targets.
A Note on Hariot's Method of Obtaining Meridional Parts
Authors: Pepper Jon V.
Published: January 2010

In an article in thisJournalsome years ago, the late Professor E. G. R. Taylor and Dr. D. H. Sadler drew attention to and discussed Hariot's calculation of meridonal parts. The question was raised but not answered as to ‘how Hariot discovered the extremely complex and far from obvious method’ that he used. This note draws attention to a possible, and indeed a very likely, way in which the method may have been discovered.

The conformal property of the stereographic projection of the surface of a globe from a pole on to its equatorial plane has been known since antiquity. It is used in the design of the astronomer's astrolabe. Hariot's manuscripts contain in more than one place a diagram for a proof of the property. One of these is reproduced in a recent article on Hariot. Halley, in an article on meridional parts, says of the conformal property, ‘But this not being vulgarly known, must not be assumed without a Demonstration’. From this result he obtains the formula for meridional parts, unaware that the same proof may have been used almost exactly a hundred years previously. In fact, he says, ‘I hope I may be entituled to a share in the emprovements of this useful part of Geometry’ on the basis of ‘having attained … a very facile and natural demonstration of the said Analogy’.
The Journals of Captain James Cook
Authors: Ritchie G. S.
Published: January 2010

FOR some 15 years past, Dr. J. C. Beaglehole has been editing the Journals of Captain Cook for the Hakluyt Society. These embrace the three great Pacific voyages, and it is a happy circumstance that the two volumes covering the third voyage, and which complete a series of four massive volumes, have been published by the Cambridge University Press in 1967 in good time for the 200th anniversary, on 26 August this year, of the sailing from Plymouth of Cook in the Endeavour on his first great voyage to the Pacific.

Having loosed the topsails as a signal for sailing and hoisted a Jack at the fore topmast to inform Mr. Banks to come on board on 25 August 1768, Cook sailed in Endeavour next day. The undramatic entry in his journal began—‘At 2 p.m. got under sail and put to sea having on board 94 persons including Officers, Seamen, Gentlemen and their Servants, near 18 months provisions, 10 Carriage guns, 12 Swivels with good store of Ammunition and stores of all kinds’.

Now, with these four volumes, the Hakluyt Society, for the first time, has made available to us the daily entries set down by Cook from that first day of sailing in 1768, throughout the three voyages, until his final entry on 17 January 1779.
Temperature Frequencies Near the Flight Level of S.S.T. Aircraft
Authors: Wehry Werner
Published: January 2010

Temperature frequencies near the flight level of S.S.T. aircraft are here treated with regard to the areas Western Europe–North America–North Pacific. The used values are taken from charts of the 50-mb level (ca. 20 km.). They are divided into three groups: (1) Temperatures higher than standard temperature, i.e. higher than - 56° C (Figs. 1, 2) showing very clearly the big North Pacific warm area, (2) values higher than -46° C (standard temperature plus 10° C) (Figs. 3, 4), mostly expressing the polar warming in summer, and (3) temperatures lower than -65° C (Fig. 5), only occurring in winter and concentrated in the European sector of the Arctic. These effects are described along some flight routes.
Radar Training for Blind Pilotage
Authors: Wepster A.
Published: January 2010

For some years the principal maritime nations have provided sea-going and future Masters and mates with some form of radar simulator training. These training courses, although differing in duration, subject material, training method and technique, had one common aim: to familiarize responsible sea-going personnel with radar as an instrument. They taught understanding of the various instrument controls, picture or display interpretation, plotting and anti-collision tactics based on the existing international Rules of the Road and Admiralty Court jurisprudence: and all this for open-sea conditions where the Master is sole master of the situation and with no outside adviser at his disposal. Many Masters and mates have followed these very necessary and useful training courses and many more will undoubtedly follow, for nobody should today go to sea in a responsible position as Master or officer of the watch without such training. Recently, pilot authorities have started to send their pilots to the same courses and again this is a step in the right direction.

A recent survey by Burger and Corbet (Welsh Institute of Technology) has furthermore shown that those trained do not seem to obtain full advantage of the acquired knowledge, once they are back in actual practice. This fact plus the fast technical advances in electronics and consequently new radar techniques should eventually lead to the institution of refresher courses.
Groundings
Authors: Van de Ree Andries
Published: January 2010

In this paper, which appeared in an earlier version on the back of a U.S. Naval Oceanographic Office pilot chart of the North Atlantic, the author first of all examines the causes of groundings; four typical cases are then described and analysed and lessons drawn from them. Finally, conclusions are drawn about the human behaviour patterns which lead to grounding, suggestions made about the effect of these patterns and the mariner's mental and physical fitness.
Radar Navigation Simplified
Authors: Bramhill W. F.
Published: January 2010

This paper describes a radar technique developed in the course of practical experience in cross-channel ferries, high-speed very manœuvrable craft. The principles of the parallel index system of radar navigation are treated in the Admiralty Manual of Navigation, Vol. I.

A practical radio operator does not have to translate consciously the sounds that he hears into morse symbols and then into letters of the alphabet. In the same way an experienced radar operator can become adept at interpreting a relative radar display without actually drawing the vector triangle; the saving of time is important in multitarget situations. The emphasis in the system described here is upon the relative motion which is directly observed on the radar screen.
Some Human Factors of Aircraft Accidents Involving Collision with High Ground
Authors: Ruffell Smith H. P.
Published: January 2010

As air traffic is expanding rapidly, more and more people are exposed to the possibility of accident. Although safety per passenger-seat mile continues to improve; because of the increasing capacity of aircraft this does not necessarily mean that the accident rate per trip follows the same pattern. The majority of accidents happen during take-off and landing but they are not necessarily associated with loss of life. The application of crash survival factors to structure and improvement in the restraint equipment for crew and passengers; the provision of rapid exit facilities and the reduction of the chances of conflagration have all played their part in improving the chances of survival.

Accidents involving collision with high ground on the other hand are almost always catastrophic and usually fatal to all the occupants. The statistics issued by I.A.T.A. show that some 40 per cent of all passenger deaths, in the airlines contributing figures, are due to this cause. Because of this it is imperative to consider every aspect of them that might lead to their reduction.
The Ethics of Using Large Tankers
Authors: Kemp J. F.
Published: January 2010

COMMANDANT OUDET'S paper ‘The Black Flood’ is a masterly analysis of the circumstances surrounding the loss of the Torrey Canyon. We have come to expect contributions of this standard from Commandant Oudet, so much so that one wonders whether the sort of international tribunal which he advocates would be more effective in pointing to the lessons to be learned from casualties than Commandant Oudet's own work has been for many years past. In his discussion of the Torrey Canyon loss, Commandant Oudet raises the question of whether the size of tankers should be limited. This question has been voiced elsewhere with the implication that, economics apart, the trend towards larger and larger tankers is a bad thing. It deserves a more detailed study.

To simplify this study a hypothetical case is considered in which a company has to transport oil at a rate of 200,000 tons per week between two ports where the round voyage takes two weeks. In theory this could be done using one 400,000-ton tanker, two 2000,000-ton tankers, …sixteen 25,000-ton tankers, …forty 10,000-ton tankers…. Economic considerations favour the use of large tankers provided there is sufficient water at the two terminals and enroute, but is this morally justified in view of the possibility of repetitions of the Torrey Canyon incident?
Line of Position from a Horizontal Angle
Authors: Seddon J. Carl
Published: January 2010

A horizontal angle between two charted objects provides a line of position and two angles between three or four objects will provide a fix or running fix except in the unique case of a ‘swinger’ or ‘revolver’. The method is faster than the conventional three-arm protractor.

A pelorus is frequently used to obtain two or more bearings for a position fix with generally sufficient accuracy. In rough weather the fix may not be particularly accurate, especially if the charted objects are a long distance away, such as lighthouses. If greater accuracy is desired, one solution is to use a sextant held horizontally to measure the two angles between three charted objects, plotting the fix by means of a three-arm protractor. The angles must be less than the 120-degree capability of the sextant and must be taken essentially simultaneously unless the snip's speed is slow. In some cases, it may be found that two objects lie to starboard and two to port, but the angles between the pairs exceed 120 degrees. The three-arm protractor cannot be used in this case. The method to be described will provide a fix or running fix without using a three-arm protractor.
Application of a Manœuvre Diagram to Multi-ship Encounters
Authors: Jones K. D.
Published: January 2010

The four papers which follow were presented at the Conference organized jointly by the European and American Institutes of Navigation in Hanover from 2–5 October 1973. A summary of all the papers was given in the last number of the Journal.
Precision Clocks as a Basis for a Navigation System
Authors: Jones S. S. D.
Published: January 2010

The technological history of navigation and that of time measurement have proceeded side-by-side for centuries and have interacted one upon the other. Improvements in navigation sensors have stimulated corresponding improvements in chronology and, more recently, improvements in the technology of time measurement and frequency control have in turn stimulated developments in navigation techniques.

Prior to the seventeenth century the available methods of time measurement were very crude but, in terms of accuracy, were consistent with the performance of the very imprecise sensors that were available for dead reckoning. The sand-glass provided a reasonable match, in terms of accuracy, to the Dutchman's log.
The Place of Time/Frequency and Space Technology in Relative Navigation
Authors: Wright T. M. B.
Published: January 2010

Radio-navigation systems in which position is determined as the intercept of two range-difference hyperbolae require a minimum of three transmitters to provide a pair of base lines, which are inclined to each other at an angle as close to 90° as practicable. Calculation of position in such systems, e.g. Decca, Loran &c., is generally a relatively complex process as the hyperbolae intersect at a random and widely varying angle.
An Examination of Criticisms of Automatic Radar Plotting Systems and their Advantages in Relation to Manual and Semi-auto Systems
Authors: Wylie F. J.
Published: January 2010

Criticism of the automatic (computerized) plotting systems has so far concentrated on the supposed danger of inadvertent hiding, through immaculate presentation, of the effects of radar, gyro and applied own speed errors, which could lead to false assumptions on the situation being made. However, although not stated in the criticism, the errors in question affect all methods of plotting, so that if the charge is valid it is a challenge to the usefulness of radar plotting as an aid to avoiding collision at sea.
Shipping Routes—an Eastern Maze
Authors: Thompson P. A.
Published: January 2010

While a great many areas in the world which contain shipping focal points have been designated as routing areas, and in most cases very successfully organized to ensure a safe flow of vessels through them, one area remains outstanding without any attempt having been made to regulate or control the traffic. This is the stretch of waterway in the Malacca and Singapore Straits from One Fathom Bank, lying some 28 miles to the westward of Port Swettenham, to Remunia Shoals off the SE. corner of Malaysia, a route containing many navigational hazards ranging from shoal-water to periods of seriously reduced visibility, and being used by high density traffic including vessels of every type and size.
Inter-relation of Temperature and Wind on the Route London—New York at 50 mb
Authors: Crossley A. F.
Published: January 2010

The statistical relation between wind and temperature in the lower stratosphere is not only of theoretical interest but is of practical concern for the operation of supersonic aircraft since for example the incidence of abnormally high temperature together with strong head-winds could substantially increase the time of flight and reduce the pay-load. Temperature and tail-wind component have been correlated on the great-circle route between London and New York at 50 mb. The route was divided into six legs of approximately 500 nautical miles; at the mid-point of each leg, temperature and tail-wind component for an eastbound flight were obtained from daily charts for the period of the International Geophysical Year and its extension, July 1957 to June 1959 (U.S. Weather Bureau, 1960–63). Seasonal correlation coefficients were evaluated for each leg and for the route as a whole. The seasons in the lower stratosphere in middle latitudes differ from the conventional seasons except in summer (June–August). Although autumn has been taken as September–November, it appears that the transition to the winter type of circulation is usually completed by late October so that November should strictly be included in winter. However, the period December to March has been taken for winter; conditions in March are very variable from one year to another but on balance this month is probably more appropriate to winter than to spring.
The Dioscures Project
Authors: Manuali B.
Published: January 2010

In January 1967 the Centre National d'Etudes Spatiales and the Secrétariat Général à l'Aviation Civile agreed on the definition of the main characteristics of the Project Dioscures, a system for telecommunications, air traffic control and navigation by means of satellites. Since then, technical studies have been carried out and the main equipment is being developed. The proposed system will enable air traffic control centres to provide continuous position determination for aircraft in the common visibility zone of two geostationary satellites. Furthermore, it will establish dependable and good-quality communication links between aircraft, control centres and other users (airlines and shipping companies, meteorological services, &c.). The system will initially be implemented over the Atlantic, mainly to serve the North Atlantic region, to be progressively expanded to cover the whole world.
Comparison of Radar Sea Echoes with Stereophotogrammetric Pictures of the Sea Surface
Authors: Freiesleben H. C.
Published: January 2010

Using a Kelvin-Hughes radar photoplot an investigation of sea-clutter patterns on the radar screen was carried out during two voyages in the Atlantic during 1964 and 1965. A physical explanation of sea clutter has not yet been produced. The Use of Radar at Sea states (page 101): ‘In almost all sea conditions there will be an area of sea clutter around the ship. The fronts of waves give stronger echoes than the backs and therefore the clutter area will not be symmetrical about the ship.… If the movement of the sea is largely due to swell there will be a wider space between echoes although they will extend to some distance. Lines of rollers sometimes produce very distinct echoes.’
Amending the Collision Regulations
Authors: Parmiter G. V.
Published: January 2010

A previous paper, developing the idea of automated routing of vessels stated ‘the full scope of automated systems at sea is inconceivable in terms of compliance with the old (collision) Regulations. Only an entirely new code of manœuvre will give the dimensions and scope needed.’ Again, it was suggested that the Collisions Regulations would need to be completely re-thought and re-written in the light of present capabilities and possibilities. This paper, while not endeavouring completely to re-write the Collision Regulations, tries to outline the form the new Regulations should take without entering into too much detail, with particular relevance to the traffic separation schemes presently under consideration by Imco and leading to the future prospect of complete automation as envisaged in the article under reference.
Exploration with a Computer on Rhumb-line Sailing
Authors: Moss B. J.
Published: January 2010

The navigator is frequently faced with the task of finding the course and distance along a rhumb-line between two places on the Earth's surface.

The following paragraphs tell of a two-part investigation into the methods of calculating rhumb-line courses and distances.

Part I deals with a comparison of the methods used and the results are presented in graphic form.

Part II considers the various corrections that may be applied to mean latitude sailing to get better results.
Direction Indication Lights
Authors: Anguish H. V.
Published: January 2010

A Recent Admiralty Notice to Mariners (No. 1555/1968) advises that a vessel trading the southern North Sea and the English Channel has been fitted with experimental direction indication lights in order to indicate to an approaching vessel the direction in which she is altering course and the duration of the alteration. The positioning of these lights are 10·5 ft. higher than the after masthead light and 4 ft. outboard on each side of the centre line, and they are coloured red to port and green to starboard. When altering course the appropriate light flashes until the vessel is steadied up on her new course.
The Maritime use of V.H.F. Radio-telephony—Present and Future
Authors: Corbet A. G. , Thomas D. H.
Published: January 2010

During the last decade virtually every merchant vessel of any consequence has been equipped with v.h.f. radio-telephony equipment. It had been hoped by many that the emergence of this remarkable and widely available communication facility would have been recognized in the recently (1972) agreed International Regulations for Preventing Collisions at Sea, as a means of helping to ensure that no cancelling actions would be taken by two vessels trying to avoid each other. However, for a variety of reasons, this opportunity was not grasped by the Imco working party on the Collision Regulations and consequently was lost at the International Conference held in October 1972.
The Vinland Map
Authors: Taylor E. G. R.
Published: January 2010

The Vinland Map, published with considerable publicity as ‘the most exciting cartographic discovery of the century’ by Yale University Press in 1965, has now, on the evidence of spectographic analysis by Walter McCrone Associates of Chicago, been virtually proved to be a modern forgery. The details, which have appeared widely in the press and were the subject of a meeting at the Royal Geographical Society on 4 February 1974, need not concern us here. The interest in Professor Taylor's paper written in 1963 well before the map's publication, is that working from measurements on a facsimile reproduction and with her own unrivalled knowledge of early cartography she was able to establish, at any rate to her own satisfaction, that the Old Map, as she calls it throughout, was a fake. She was the first scholar to cast serious doubt on the map's authenticity, and needless to say her views were hotly contested.
II—Position Fixing in the North Sea
Authors: Blaiklock K. V.
Published: January 2010

Means for position fixing in the North Sea using Decca have expanded greatly over the past 10 years, since the first rig was positioned in 1964, and without precise knowledge of position much of the work observed at sea is valueless. Some offshore problems have therefore changed or have been solved, others remain.
I—The Diameter of Evasion for Crossing Encounters
Authors: Oshima Ryozo , Fujii Yahei
Published: January 2010

The traffic capacity of a crossing of two fairways is one of the most important problems in marine traffic engineering and a few papers published in Japan deal with this subject, either by theoretical analysis or mathematical simulation. However little is yet known on the size of domain or diameter of evasion, without which any quantitative estimation of capacity is almost impossible. Partly for this purpose a year-long observation was performed in the eastern part of Bisanseto, a strait in the Seto Inland Sea, where the number of crossing encounters is the largest in Japan.
II—The Probability of Stranding
Authors: Fujii Y. , Yamanouchi H. , Mizuki N.
Published: January 2010

Fujii shows that the collision diameter is about 1/10,000 of the ship length; this figure is to be interpreted as meaning that skilful manœuvres decrease the collision frequency to about 1/10,000 and, since the geometrical collision diameter is of the same order as the ship length L, attention has to be paid to ‘collisions’ which include even slight contact. The probability of a mismanœuvre which leads to stranding is studied using the marine traffic accident ‘library’ of the Japanese Association for Preventing Sea Casualties and the Report on the Marine Traffic Survey of the same Association. The library includes records of casualties in the original cards both of Marine Casualty Statistics and Statistics of Marine Accidents Requiring Rescue. The authors were members of the working group which prepared both the library and the Report. In this paper stranding includes any kind of grounding unless intentional, e.g. after collision or fire, and includes groundings with slight damage such as bottom contact.
III—The Effect of Darkness on the Probability of Collision and Stranding
Authors: Fujii Yahei
Published: January 2010

There is no doubt that visibility influences the probability of collision and stranding and even a full moon, which gives a brightness of only 0·2 lux, seems to reduce the probability compared with a dark night; there is a much greater difference in the brightness by day (several thousand lux even with cloud) and at night. However the number of accidents in a seaway is influenced by many factors, such as traffic density, average speed, encounter condition, visibility, the helmsman's skill, availability of information &c. Of these factors, traffic density has most influence on the probability and this influence must be removed in order to study the influence of brightness. The present writer has shown that the danger of collision is roughly proportional to the square of the traffic density, and therefore proportional to the square of the traffic volume. Diurnal changes in the number of accidents and in traffic volume are therefore used to estimate the ratio of the danger by day and by night.
An Abacus for Windward Performance
Authors: Elliot J.
Published: January 2010

The prudence of determining the best windward and running courses for sailing yachts can be seen from Fig. 1 in which the heart shaped curve represents a polar diagram of yacht performance with respect to the true wind direction. It is a diagram of yacht velocity V and the angle α between the yacht's track and the true wind direction. The gap in the curve dead to windward is an area over which no performance is possible, whereas any destination lying outside this zone can be reached directly; there is only one sailing angle at which a destination lying between X and Y can be reached the quickest. A similar situation occurs on the running point of sailing where the curve may have an inflexion, i.e. there is profit in tacking a course downwind.
‘Behaviour Patterns in Encounters between Ships’
Authors: Spooner G. R.
Published: January 2010

A few hours after reading the above article in the October Journal an incident occurred which highlighted the dangers indicated by Captain Kemp. At night, but in clear weather and deep water, and with no navigational hazards, a ship was reported at Green 30, 3 miles, with a C.P.A. of 2 cables to starboard. This was unnecessarily and dangerously close and the officer-of-the-watch (a relatively inexperienced watchkeeper) proposed standing on to 1 mile and then altering 10 degrees to port to open the range.
A New Use for the Traverse Table
Authors: Sorab Pesi
Published: January 2010

There are occasions when it can be useful to plot bearings from objects not shown on the chart, for example a radiobeacon or a lighthouse outside the coverage of the chart in use. The traverse table may be used for this purpose in the following manner:

1. Establish the latitude and longitude of the object (radiobeacon, lighthouse, &c).

2. Choose a convenient latitude from which to plot the bearing and calculate the difference of latitude between it and the object.

3. With the bearing as course extract from the tables the departure corresponding to this d. lat.

4. For the middle (or mean) latitude derive the corresponding d. long. and apply it to the longitude of the bearing object.

5. Plot the bearing, as a position line, through the chosen latitude and the longitude thus derived.
Rules for Today's Circumstances
Authors: Kemp J. F.
Published: January 2010

There are three main reasons why the rules for preventing collisions at sea need revising:

Rule 21 is unsatisfactory. This is particularly the case in encounters between vessels of widely different speeds and manœuvring capabilities when Rule 19 may require an unreasonable manœuvre from the slower and more ponderous craft and Rule 21 at the same time prohibits manœuvre by the more easily handled craft.

If in an encounter the giving-way vessel does not take action in good time, Rule 21 requires that the other vessel must maintain a collision course until the situation becomes so dangerous that action by one vessel is insufficient to prevent collision. For a rule which is intended to prevent collision this seems hardly credible, but in fact Rule 21 does legislate to maintain a risk situation from a time where disengagement might be comparatively easy to a point where it is almost impossible.

It is often suggested that moderate speed in fog should be a function of the performance of the ship in question, but if Rule 21 is to be observed when vessels sight one another, then it ought to be a function of the performance of the vessel required to give way. This of course may not be known until the sighting.

Because it is unnatural to maintain course and speed into a dangerous situation, Rule 21 is frequently disregarded, particularly by navigators of fast and highly manœuvrable craft.
Rules for Use with Radar
Authors: Burger W. , Corbet A. G.
Published: January 2010

Since the introduction of the present (1960) Regulations for Preventing Collisions at Sea, we at Cardiff have noticed that the actions taken by Masters and senior officers, during simulator exercises, have been bolder and, perhaps, taken somewhat earlier than they were previously. Unfortunately, however, the actions taken by two ships approaching each other often cancel out. This is not always dangerous because the initial actions have generally been taken early enough for further action to be taken but, it does lead to unnecessary delays and frustration. We think, therefore, that it is desirable that any new Regulations should contain a set of rules of action for a vessel detecting another, on a collision course, by radar only.
Unitized Cargo Transportation
Authors: Van de Ree Andries
Published: January 2010

The transport of cargo is not of itself a navigational subject; it is however the purpose of nearly all marine navigation and a development such as ‘containerization’ which is having such a profound effect on the nature of shipping cannot fail to be of interest to navigators at sea. In this paper, a version of which appears on the U.S. North Atlantic Pilot Chart for May 1969, Mr. Van de Ree of the Ship Analysis Division of the U.S. Navy Oceanographic Office describes the background to the development of unitized cargo handling and transportation, its economic advantages and its significance for the pattern of trade at sea.
Engineering and Economic Aspects of Inertial Navigation
Authors: Sullings F. J.
Published: January 2010

It may be useful to outline the progress made in the field of inertial navigation for civil transports made since the last meeting of the Institute held to discuss the subject. After experimental evaluation work, mainly in the U.S.A. but also in this country, the first production equipment made specifically for civil use was the Sperry SGN 10 equipment made for Pan American Airways and first fitted in 1965.
Reduction of the Effect of Component Errors in Inertial Navigation Systems
Authors: Smith S. G.
Published: January 2010

The basic concept of case and cluster rotation in inertial navigation (IN) systems is introduced, and the reduction in the errors caused by changes in gyro and accelero-meter biases is illustrated. The general properties of cluster rotated systems are summarized and it is concluded that, although errors inside the Schuler loops may be drastically reduced by rotation, care must be taken to avoid error sources outside the loops.
Collision Avoidance in the Air
Authors: Hunter I. M.
Published: January 2010

This paper describes and attempts to assess the viability of the airborne collision-avoidance system based on time-frequency techniques which is proposed, for use within ground-based control systems, by the Air Transport Association of America.
The Loss of Two British Trawlers—A Study in Wave Refraction
Authors: Pierson Willard J.
Published: January 2010

The author is Professor of Oceanography in the School of Engineering and Science of New York University and this paper was prepared for the Imco joint ad hoc group for the study of external forces affecting ships. Reviewing the circumstances attending the loss of the trawlers Blue Crusader and Boston Pionair in 1965 he attributes them to high pyramidal seas caused by the crossing of wave trains refracted in water of varying depth. The use of model experiments, air photography and laser altimeters is suggested for verifying the theoretical conclusions, in the light of which corrective measures might be taken when navigating under such conditions.
Ocean Voyaging under Sail
Authors: Tilman H. W.
Published: January 2010

When advancing years put the Himalaya out of reach my thoughts turned to sailing and the chances of combining this with climbing, two activities that have much in common. After an apprenticeship in the form of two voyages with Bobby Somerset—whom I still regard as the maestro in small boat matters—I acquired Mischief solely with a view to crossing the Patagonia ice-cap. The ice-cap had not then been crossed and since all attempts from the Argentine side had failed I thought of tackling it from the sea. Mischief, 45 ft. long, 13 ft. beam, 7 ft. 6 in. draught, of about 30 tons T.M., had been built in 1906 as a Bristol Channel pilot cutter.
A Stranding in the West Indies
Authors: Oudet L.
Published: January 2010

In January 1971 the liner Antilles sailing among the islands of the same name ran aground in the neighbourhood of the Grenadines, between the islands of Mustique and the Pillories. Nobody was injured but the ship was lost. An inquiry by a maritime court in the following October acquitted the Captain and this came as a great relief to the seafaring fraternity because it was difficult to see how a sailor at the top of his profession could knowingly have navigated with such imprudence. The fatal rock was not shown on the chart and everyone knows that charts are not perfect: the Master had been the victim of the inevitable.
Navigational Globes: Ancient and Modern
Authors: Cotter Charles H.
Published: January 2010

‘There are two kinds of Instruments by which Artificers have conceived that the figure of this so beautifull and various fabricke of the whole Universe might most aptly be expressed, and as it were at once presented to the view. The one exhibiting this Idea in a round solid is called a Globe. The other, expressing the same in a plaine, they tearme a Planisphaere or Map.… The Planisphaere, indeed, is a fine invention.… But yet that Other, being the more ancient, hath also the priority in Nature, and is of the most convenient forme; and therefore more aptly accommodated for the understanding and fancy (not to speake any of the beauty and gracefulnesse of it), for it representeth the things themselves in proper genuine figures.’
Traffic Distribution and Collision Rate/Size Correlations Derived from Dover Straits Survey Data
Authors: Goodwin E. M.
Published: January 2010

After reading the first two reports on the surveys of marine traffic in the Dover Strait conducted by the National Physical Laboratory, it was decided to investigate the possibility of applying the results to two points raised in recent issues of the Journal.

The first question studied was one suggested by Beattie, in his article on the first of the above traffic surveys. It was noted that there was quite a variation in the number of ships per hour passing through a given area. This could have been caused by a systematic tendency for ships to come through in clusters or could be a perfectly random variation. If the variation was completely random then the frequency distribution of ships per hour should follow a standard statistical distribution known as the Poisson distribution. For each of six separate distributions obtained from the results of the surveys on 26 February to 1 March 1971 and 27 April to 29 April 1971, the appropriate theoretical Poisson distribution was fitted and tests made to assess how close the theoretical and observed distributions were. The results of the calculations are summarized below in the table.
Marine Traffic Engineering: An Introduction to Marine Traffic Engineering
Authors: Silverleaf A.
Published: January 2010

The principal purposes of this introductory paper are to identify and describe the main aspects of marine traffic engineering, and to suggest ways in which traffic engineering principles and methods developed for land and air transport systems may be applied to marine problems. Traffic engineering is a relatively new branch of engineering science, but it was quickly and widely recognized as essential in ensuring that all forms of land and air transport operate safely and efficiently. However, although sea transport is a long established activity, it is only during the past few years that marine traffic engineering has begun to emerge as a separate aspect of this broader scientific discipline.
Modelling Encounter Rates in Marine Traffic Flows with Particular Application to the Dover Strait
Authors: Draper J. , Bennett C.
Published: January 2010

A general programme of work with the overall aim of reducing the incidence of collisions in the Dover Strait has been commissioned by the Marine Division, Department of Trade and Industry. As part of the programme the Operational Research Unit in DTI is developing mathematical models of traffic flow, using inputs of data provided from the surveys mounted by NPL and described in the paper by Johnson and Wheatley.
The Constraints on Traffic Flow Imposed by the Terminal
Authors: van Dixhoorn Ir. J.
Published: January 2010

A Marine terminal influences the flow of traffic which sails at a lower speed and is congested. Navigation must be in accordance with the total amount of traffic and not, as in the open sea, in accordance with one or two other ships. Shore based authority must be accepted. The flow of traffic along the coast passing a terminal meets this congestion, certainly if the terminal is in shallow water frequented by large vessels. Crossing also adds to the congestion for the passing flow of traffic. The congestion will be less if the marine terminal and outer channel can accommodate the total traffic flow.
A Survey of Marine Accidents (with Particular Reference to Tankers)
Authors: Grimes C.
Published: January 2010

A Survey of marine accidents has been carried out as part of a study aimed at predicting the probable future frequency of accidents likely to result in pollution of the United Kingdom coastline. The survey covers all marine accidents in the North-western European area, i.e. North Sea, English Channel, Irish Sea &c, and all tanker accidents world-wide; it covers the 10-year period 1959–68 inclusive.
Ship Manœuvring Characteristics
Authors: Paffett J. A. H.
Published: January 2010

Successful ship handling depends upon acquiring the right information, making the right decisions and performing the right manœuvres; this paper concentrates upon the last of these. Manœuvring here is taken to include starting, stopping and steering. The ship is a vehicle with remarkably low resistance to motion; merchant ship drags commonly lie in the range one-hundredth to one-thousandth of the all-up weight force. This is comparable with that of a railway wagon (say 1/500 of its weight) and the low drag accounts in part for the ship's extreme economy as a carrying machine.
A Shipowner's View of Traffic Regulation
Authors: Adams R. B.
Published: January 2010

The shipowner is the customer and his views are coloured by whether what he buys, and ultimately is going to pay for, is what he wants. It is difficult to reconcile even the conflicting interests of various divisions of a single company for, say, a Dover Strait scheme. The division may operate passenger ships, cross-Channel ferries, deep-draught tankers or conventional cargo ships. The main product that shipowners are buying is increased safety, with a marginal bonus in some types of traffic regulation of possibly saving time in conditions of poor visibility, provided the scheme is cost effective. Most shipowners recognize a moral responsibility for ensuring the best possible conditions for safe operation of their ships and for avoidance of environmental pollution.
Shipboard and Shore-based Equipment and its Uses
Authors: Foley F. M. , Heal H. T.
Published: January 2010

When considering what equipment is to be fitted either in the ship or ashore in order to ensure safe navigation in conditions of high traffic density, we can to some extent be guided by looking at what has happened in the aircraft world where these problems have been present for a long time. Here considerable use is made of radar and of radio navigational aids. Before assuming too readily that the same will apply in the marine world, we should perhaps recall that radar and the hyperbolic radio aids were born during World War II, and that since then fundamentally new techniques in navigation have been developed which should be examined to see if they have any bearing on our present problem.
Human Factors which Affect Reliability and Efficiency
Authors: Jones K. D.
Published: January 2010

In assessing the human problems which may occur in the development of a traffic system in an offshore area, some lessons may be learnt from the work which has been done on the similar problems arising in port approaches. There are several fundamental differences between the port and offshore problems such as the direction and density of traffic flow, the parochial as opposed to the international legislation and the difficulties that attend the positive identification of passing traffic. These considerations mean that it must not be supposed that the solutions which have been discovered in the port approaches may be simply transferred to the offshore case, but the similarity of aims in the two systems make a comparative study worthwhile. Basically, each authority must first legislate to allow control and guidance of the traffic. From this right to control must stem the obligation to organize the traffic into a scheduled stream, but this regulated stream will only reduce the risk of conflict if the schedule can be maintained by surveillance, communication and the cooperation of the mariner.
Manœuvre in Response to Collision Warning from Airborne Devices
Authors: Ratcliffe S.
Published: January 2010

Two of the proposed airborne collision-avoidance devices at present under discussion are the A.T.A. time-frequency system and a later proposal termed SECANT. The present paper attempts to discuss the geometry of the escape manœuvres associated with the use of one or other of these devices; the electronic problems involved in these ingenious but intricate devices will here be largely ignored, and discussion will be confined to the problems facing two conventional aircraft in an encounter at an appreciable altitude.
A Shipower's View of Traffic Regulation
Authors: Adams R. B.
Published: January 2010

Many may consider it presumptuous of the guinea-pig to voice an opinion on the experiment to which he is to be subjected. I hope this is not so, because I view the shipowner not as the guinea-pig but as the prospective customer for any advances which are made in marine traffic engineering technology. The shipowners of the world are undoubtedly going to pay directly or indirectly for any traffic regulation schemes which are set up. It is certainly not part of my theme that the customer is always right—he may not know what he wants until he has been subjected to a promotional advertising campaign and he may be excessively gullible in swallowing such propaganda—but there is possibly value in the customer saying what he thinks he wants and airing doubts he may have before he is subjected to these pressures. I therefore welcome the opportunity to give a shipowner's view on traffic regulation.