It is probable that within the next ten years marine transport technologists will be faced with some difficult choices in relation to ship propulsion for an era of high fuel prices. They will have to consider (i) the continuation of conventional power driven vessels with greatly improved engines, or low speed operations; (2) the development of high speed nuclear powered ships; and, (3) the use of sail. Whether the latter will be adopted to any significant extent for ocean transport will depend on the oil supply situation in the 1980s and 90s; developments in ships' engines; and, more importantly, the philosophy then prevailing relating to the conservation of the world's non-renewable resources.

There are a number of ways of reducing the running cost of existing ships by making use of power sources which are freely available to them in their environment. This paper first of all considers briefly some possibilities other than wind power and then discusses the use of wind as an auxiliary source of propulsion in power driven ships.

Ocean Currents. Ship navigators of course already make considerable use of ocean currents when planning economical voyages. However a number of rafting voyages made for various reasons in the last few years point to the possibility of sending bulk cargoes at slow speeds across some parts of the seas carried principally by the currents. The principal problem is perhaps the pure financial one of taking the capital value of the cargo out of circulation for the time involved in such transportation.

The big square-rigged ship, contrary to popular or ignorant view, was (or could certainly be) a most effective machine for the conversion of the sea winds into power in and by her sails, and could make useful long voyages carrying heavy bulk cargoes at minimum cost and minimum loss, while at the same time offering that rarity of these days—a good measure of contentment and satisfaction for her officers and crew. She was not—and I should think never was—a lumbering old ‘windbag’, more or less drifting about the seas from one port towards another, hopeful of arriving somewhere some day. When for example, we sailed in the four-masted barque Parma from an outport in Spencer Gulf, South Australia, bound non-stop towards Falmouth, Plymouth, or Queenstown for Orders (as the old charter parties read), with five thousand tons or more of grain in sacks stowed thoroughly well down below, we did not set out hopefully on a drifting-match vaguely in the direction of North Europe, some 15, 000 miles away.

The pattern of surface winds on an ideal non-rotating uniform Earth would be related to the distribution of surface temperatures. This would lead to atmospheric pressure gradients which, in turn, would produce surface winds. The effect of the Earth's rotation produces the so-called ‘Planetary Wind System’, and the actual pattern of surface winds is often considered to be a modification of this. But many factors influence the global wind system to such an extent that the explanation of any part of the system at any given time is a matter of considerable complexity. Moreover, experience has amply demonstrated that despite the close attention of physicists the accurate forecasting of winds for more than a day or so ahead has not met with hoped-for success.

If sailing vessels are to return to the oceans to carry freight, then, because of different hull and sail characteristics, the climatological routes will have to be re-assessed, probably by means of computer methods. Weather routing techniques for assisting a sailing vessel to follow the safest and most economic route across an area where barometric depressions are dominant will have to become more refined, and updated and transmitted by radio more frequently than is the case at present.

This paper reviews the research carried out at the University of Hamburg on the predicted performance of the Dyna Ship, a project for an advanced sailing merchantman. The proposed rig incorporates a series of unstayed hollow rotatable masts with terylene sails set along aerodynamically curved yards. The masts and sails are handled hydraulically by remote control from the wheelhouse.

Sailing ship research at the Institut für Schiffbau (IfS) of Hamburg University probably began with a paper presented by Thieme to the Schiffbautechnische Gesellschaft (S.T.G.) in 1955 on the mechanics of sail propulsion. When during 1961–6 the Hamburg Research Council promoted a broad research programme on wind forces on ships, covering all current modern ship types, the opportunity was taken to include also the problems of wind propulsion. This part of the investigation was especially stimulated by an inquiry by Wilhelm Prolss, who proposed a new height-restricted wind propulsion system for large ships in line with modern technology and aerodynamics, now known as the Dyna Ship.

Since 1960 there has been a revival of interest in the Chinese, or junk, rig for small sailing yachts, and an increasing number of seagoing cruising boats are now appearing with it. It may therefore be appropriate to consider what, if any, application the rig could have to commercial sailing vessels in the western world.

The rig carries only one fully-battened sail on each mast, and may have any number of masts from one upwards. In its larger sizes the sail, complete with its yard, battens, and boom, is very heavy, and the whole weight has to be carried by one or more halyards from the masthead. Traditionally, and preferably, the mast is completely unstayed, being supported only at the step and the partners and standing up like a tree, or cantilever.

It is difficult, somehow, to be completely convinced that the world's fuel supplies are about to dry up leaving us in a state of nature with modern technology marooned hard and fast up the proverbial creek. The end of the world itself has been prophesied at regular intervals since the beginning of time and has not yet come to pass. Again, throughout recorded history mankind, with only minor hiccups, has somehow always managed to go forward technically and never backwards. It is difficult somehow not to relax into a comfortable state of Micawberism and to reckon that something is bound to turn up in the fifty or so years we seem to have left to buoy us all up again and carry forward the kind of civilization we all take for granted. It is not surprising therefore that some basic air of unreality tends to cling around any discussion on a return to the use of wind power for propelling ships. It must be the first time ever that mankind has seriously discussed a return to an outdated and largely dead major technology.

‘Kalman Filter Techniques’

M. J. Dove whose paper ‘Kalman Filter Techniques in Marine Integrated Navigation Systems’ was published in the January number of the Journal was described as coming from Southampton College of Technology. This should have read School of Maritime Studies, Plymouth Polytechnic.

This paper, by the Assistant Chief Electro-dynamic Engineer of the British Aircraft Corporation, was originally presented at the Annual General Technical Meeting of the Guild of Air Pilots and Navigators in September 1976.

This paper discusses a programme being carried out jointly by the British Aircraft Corporation and Hawker Siddeley Aviation into the design of flight decks for civil transport aircraft scheduled to enter service in the 1980s. The flight decks of today have evolved as a result of experience gained since manned flight began; it would be foolhardy to ignore this background and in applying new technology care must be exercised in preserving, as far as possible, conventions and practices which have long been established.

This paper was presented at a meeting of the Bristol Channel Branch of the Institute i n Cardiff on 28 April 1976.

The work and life of John Thomas Towson falls neatly within the professional group so aptly styled by the late Professor E. G. R. Taylor as the Mathematical Practitioners. Born in Devonport in 1804, Towson was educated at Stoke Classical School in that town and on leaving school followed his father's trade as a chronometer maker. When only 22 years of age Towson invented a device for banking the balance of a chronometer and his invention was communicated to the Society of Arts in 1826.

In 196 two papers by Captain Wylie on ‘Legal aspects of radar and collision’ were published in this Journal (18, 203, 402). Captain Wylie here reviews some of these cases, and other similar cases, in the light of the further information that might have been available on the bridge had the vessels concerned been equipped with modern automatic radar plotting equipment.

The object of this series is to examine the circumstances of a number of collisions, selected at random, to see whether the various encounters would have been likely to develop adversely had either or both ships been equipped with a fully automatic radar plotter (FARP). The argument could of course have been developed using various devised situations, but it was felt that a more convincing result would be achieved against a background of documented disasters. All the incidents chosen have been the subjects of Court Cases or Official Investigations; only in the Andrea Doria–Stockholm collision was there no conclusion, as the case was withdrawn from the New York District Court after the taking of evidence from the deck officers.

Acoustic transponders are employed in underwater navigation in situations in which a high degree of accuracy is required. Typical applications include underwater search, mapping, photography by a submersible or a towed vehicle and positioning of underwater work systems. The network of transponders, of which there may be only two or three, or which may be very extensive, is implanted by a support ship or by a submersible. The network can be located geographically by a satellite navigation equipment to an accuracy of 0·25 nm. This accuracy (or even accuracy within ± 1 mile) is sufficient to locate the network after a period of disuse. Acoustic navigation of a vehicle is accomplished relative to the network, to accuracies of the order of several feet.

Throughout history man has navigated himself or his vehicle; while some of the methods he has used have remained unchanged through the centuries, other methods have been developed, and when superseded by later developments often lost. The stone age cave dweller used navigation, after chasing his quarry, to find his way back to his cave and this particular form of the art of navigation is little changed today. On the other hand the arts and the techniques which enabled early Polynesian navigators to sail the South Seas, and the crews of Arabian dhows to return to their home ports unerringly, may well be lost for all time. We do not propose to regret this; it is part of the evolutionary process that as each skill is lost it is replaced by a greater skill. The modern marine sextant can trace its ancestry back to the practice of measuring the height of a star in finger breadths used by those Arab navigators. Aerial navigation entirely, and from our limited knowledge we suggest ship navigation also, is at a point in its development where the man is being replaced by the machine, and it may be that we should assess the best way to ensure that we, as navigators, remain master of that machine.

Early in 1976 the Navigation Research Centre of the Netherlands Maritime Institute started research to develop a ‘maritime risk criterion number’ for a specific sea area. The need was urgent as the Navigation Research Centre (NRC) became more involved in marine traffic studies in the North Sea and the approaches to Dutch harbours. The main purpose is to calculate the criteria for traffic patterns in a given area as an element in the information needed to find the best regulatory solution for the overall traffic situation. The criterion should give due recognition to such elements as the traffic density, the course and speed distribution of the traffic, and the danger classes of the ships participating in the traffic.

To fulfill any specific task a certain navigation accuracy is in general required. If this requirement can be achieved by different systems the cost effectiveness will be decisive. Apart from missions which allow large position errors, medium or high navigation accuracies will normally be desired, obtained either by high technological standards or by an unsophisticated system with an updating procedure. The cost of highly sophisticated systems increases exponentially with increasing accuracy, so that our object was to find an appropriate updating system.

The first reference to western techniques of navigation in Japan is in the Genna-Kohkaisho or The Navigation Arts in the Age of Genna by Koh-un-Ikeda, written in 1618 just sixty-three years after the first Portuguese visit to Japan. During these sixty-three years the Japanese had built some western-style sailing vessels and actually used western techniques for navigation to south-east Asia. The author shows a good grasp of western navigation. For instance Ikeda had asked his teacher, the Portuguese captain Gonsaro (Japanese pronunciation) ‘Is there any method of obtaining the latitude when the sky is clouded for a short time just as the Sun or the star transits the meridian?’ Captain Gonsaro answers ‘It is of course impossible, no one in the world can ever do it.’ Ikeda suggests the possibility of estimating the altitude of the Sun or star on the meridian and one can see now that this foreshadows the famous ex-meridian method that was developed much later.

Fragments of documents and instruments identifiable as almanacs, together with the comments of ancient writers and the circumstances surrounding historical deeds indicate that almanacs have existed from the earliest attempts at the organization of time into units larger than the day. The value of such works to navigation was slight when voyages beyond sight of land were few and of short duration; nor were they readily available when books had to be hand copied. Yet the contents of almanacs had an influence on sailing; the average mariner, being neither more ignorant nor less superstitious than the merchant or farmer, was likewise subject to occult predictions when almanacs were in the hands of the astrologers.

John Hamilton Moore (1738–1807), a well-known teacher of navigation, was born in Edinburgh, educated in Ireland, and subsequently joined the Royal Navy at Plymouth. In about 1770 Moore established a Nautical Academy in Brentford, Middlesex, and in 1772 he published his popular epitome of navigation under the title The New Practical Navigator and Daily Assistant. Later he established himself at 127, Minories, near Tower Hill, where he not only taught navigation to ‘Gentlemen designed for, or belonging to the sea‘ but carried on the business, aided by his sons and son-in-law Robert Blachford, of chart-seller and purveyor of nautical instruments. In the preface to the twelfth (1796) edition of his Practical Navigator, Moore presumed that he had been enabled to have made gradual but progressive improvements in navigation as his ‘knowledge became extended through investigation’ and as his ‘judgement matured by experience’. In this edition of his work Moore styled himself as ‘Teacher of Navigation, Hydrographer and Chart-seller to His Royal Highness the Duke of Clarence’. There can be no doubt that Moore's Practical Navigator was favourably received; and, indeed, a twentieth edition was brought out by Joseph F. Dessiou (1790–1842), a master in the Royal Navy who, on retiring from sea-service, was employed in the Admiralty Hydrographic Office where he specialized in the study of tides. Dessiou's twentieth edition of Moore appeared in 1828, some 21 years after the death of its original author.