bluuebunny/crossref_metadata_2025 huggingface dataset:
Operating and Flight-planning Techniques for the Viscount
Authors: Chadwick R. H.
Published: January 2010

At the end of the summer of 1952, a series of proving flights were started on B.E.A. routes with the prototype Viscount airliner, the V.700 G-AMAV. One of the objectives of this proving flying was to design operating and flight-planning techniques to be used when normal scheduled services were commenced.
‘The Equatorie of the Planetis’
Authors: Jones Harold Spencer
Published: January 2010

In the course of collecting data for a general history of scientific instruments, Dr. Price came across the manuscript that forms the subject of this volume in the Library of Peterhouse, Cambridge. It attracted his attention because of its subject matter, because it was written in Middle English, and because the date 1392 frequently occurred. As Chaucer's Treatise on the Astrolabe was written in 1391 and is apparently incomplete, it seemed at first sight possible that the Peterhouse manuscript might be a missing part of Chaucer's Treatise, which at that time was the only instrument tract written in Middle English known to Dr. Price.
The Usability of Airfields in Gusty Winds
Authors: Wadsworth J.
Published: January 2010

The use of an airfield is controlled to a certain extent by the wind, and if the cross component of the wind on the runway exceeds a certain strength, it becomes hazardous for an aircraft to land or take off. The effect of a cross-wind component on aircraft in flight is to cause drift, whereby the path of the aircraft over the ground is inclined at an angle to the direction in which the aircraft is steered. A pilot about to land in a cross-wind must execute a certain manoeuvre to counteract the drift, otherwise on touching down the aircraft will tend to move sideways across the aerodrome, thus putting a strain on its undercarriage and perhaps tipping over on to one wing.
The Navigation Collection at the Science Museum
Authors: Chilton D.
Published: January 2010

The word Navigation still retains the broad meaning it had in 1570, when John Dee wrote: ‘The Arte of Navigation, demonstrateth how, by the shortest good way, by the aptest Direction, & in the shortest time, a sufficient Ship, between any two places (in passage Navigable,) assigned: may be conducted: and in all stormes, & naturall disturbances chauncyng, how, to use the best possible meanes, whereby to recover the place first assigned’. But for the purposes of the Science Museum it is convenient to restrict the scope of the so-called Navigation Collection to objects illustrating the development of methods of determining a vessel's position and course. Exhibits illustrating the other aspects of navigation are placed in the Marine Engineering and Aeronautical collections.
The Accuracy of Dead Reckoning in the Air
Authors: Hudson W. , Palmer E.
Published: January 2010

I was unable to attend the lecture by Mr. C. S. Durst on ‘The Accuracy of Dead Reckoning in the Air’, and I was, therefore, very interested to read the paper in the April Journal. There are many implications, and Mr. J. B. Parker has endeavoured to suggest some in his article.
The Time-distance Radar Plot
Authors: Wylie F. J.
Published: January 2010

Dr. Atkinson puts up an interesting hypothesis which I hope will not appeal to many sailors, because I do not think it offers what the navigator needs and I believe that it could be misleading. As far as concerns other plots discussed in the Journal or The Use of Radar at Sea, the criticism that they do not use all the information available is, I think, quite invalid.
Early Pole Star Tables
Authors: Waters D. W.
Published: January 2010

I cannot subscribe to Dr. Freiesleben's thesis that until the French Revolution induced a change of mind there was a big gap between men of science and seamen. It may be, as he states, that ‘in the eighteenth century there was still a remarkable gap between scientific doctrine and practice’ and it would be interesting to know the causes if this were so, but in the sixteenth and early seventeenth centuries there was, particularly in England, a quite remarkable and organized liaison between scientists and seamen with the specific purpose of improving the art of navigation. The object, as Thomas Digges expressed it in 1579, was ‘to reduce Imaginative Contemplations to Practical Conclusions’; in other words, it was to make scientific discoveries and inventions to improve the accuracy of navigation. A few examples must suffice in the space available to support this statement.
The Visibility of Stars during Twilight
Authors: Millman Peter M.
Published: January 2010

One of the problems in arctic navigation by astro is the twilight period. At this time, if the Moon is below the horizon, suitable objects for sextant observation are not easy to find. The difficulty is aggravated by the fact that on certain flight paths the arctic twilight may last for many hours. It must also be remembered that in these areas the behaviour of the magnetic compass and of radio aids are often unreliable and this increases the relative importance of astro-navigation. With the introduction of the periscopic sextant into air navigation it has become possible to pre-set the instrument for a given star or planet and satisfactory observations may be possible when the heavenly body is still below the level of casual perception for the unaided eye. In this connection it is necessary to know what stars are likely to be seen under twilight conditions if efficient flight-planning is to be carried out.
The Future of Marine Electronics Captain
Authors: Wylie F. J.
Published: January 2010

This paper was presented by Captain Wylie at the Full Assembly meeting of the Radio Technical Commission for Marine Services in New York on 26 October 1956. The subject is dealt with under three headings: Communication, Navigation and Anti-collision.

To the landsman of the western world, telecommunication is as unremarkable a part of his life as his toothbrush. To the seaman in the old tradition, it may occasionally be anathema, but to the modern mariner that feeling of isolation which came when the last mail had been collected and the shore telephone line disconnected, while sometimes a blessed relief, is becoming an anachronism. On shore, the use of the telegraph service has receded very greatly as a result of the increasing efficiency and availability of the telephone. More and more people discover and insist upon the advantage of personal contact by speech. At sea there is little difference in the desire, but a great deal in its gratification, due to lack of facilities and to failure to provide an integrated system which will serve the ship from mid-ocean to her anchor berth in port.
II—The Use of Balloons in Meteorology
Authors: Harrison D. N.
Published: January 2010

Although early meteorological records were naturally confined to the weather experienced at the surface of the Earth, as soon as meteorology began to be a science it was realized that what went on above the surface was important and that the physics of the air needed to be studied in three dimensions. An obvious illustration is the use made of cloud observations—the nature and structure of clouds, the method of their formation and their movement. Something could be learnt on those questions by observations from the ground, aided by such a simple instrument as the nephoscope. Most people, and certainly all concerned with navigation, know that the movement of clouds may be very different from the wind at the surface. It was also realized that since the atmosphere is a heat engine a knowledge of the temperature of the upper air was required. Anyone who has climbed a mountain knows that the temperature falls, and this was confirmed for the free atmosphere by observations with kites. It was clearly of interest to know whether the fall of temperature was maintained until the absolute zero was reached, and if not, why not. It is in the measurement of temperature and wind in the upper air that balloons have found their chief use.
III—Some Electronic Solutions
Authors: Hansford R. F.
Published: January 2010

The advent of true-motion radar has been a great step forward in the problem of allowing a ship to operate safely in congested waterways. Harbour radar, however, is still a requirement for two reasons; first of all it can well provide far more immediate information than is available from true-motion radar. Fig. 1 emphasizes this by showing how much additional information can only be available directly from a static site. Consequently it allows shore authorities to be advised of what is happening in conditions of bad visibility where they would otherwise be devoid of most information. This raises the problem of how the information is to be used.
I—Navigation in Polar Regions
Authors: Anderson E. W.
Published: January 2010

The main problem in polar navigation is one of direction, and the problem has two facets. First we have to measure direction and then we have to describe it. Generally, the seaman has a gyro-compass by which he can measure the heading of his ship. As you know, the gyro-compass is simply a gyro which keeps pointing towards the pole. If we have a gyro close to the north pole and pointing north, it will continue to point in the same direction however the ship turns beneath it. So also will it continue to point in the same direction if the Earth turns beneath it. In twelve hours it will be pointing south instead of north.
II—The British Transantarctic Expedition
Authors: Lowe George
Published: January 2010

Captain Scott went to the pole over the Ross Barrier, up the Beardmore Glacier (Fig. 1) which is about 100 miles long, and then on to the south pole, coming out by the same route. The great Norwegian explorer Amundsen went in from the other side over the shelf, up one of the glaciers and on to the pole. Admiral Byrd flew in and out again in 1929. Apart from these expeditions very little has been done in Antarctica and nearly all of it, apart from the fringe, is untouched.
II—The Relative Plot
Authors: Wylie F. J.
Published: January 2010

The mariner is, on the whole, a cautious creature. When he takes action, he likes to know within fairly narrow limits how much is necessary and where that much will take him in relation to all potentially dangerous objects. He has as much respect for the fire as for the frying pan.
The ‘Box’ or Pocket Sextant
Authors: Wright Frances W.
Published: January 2010

Last summer I sailed in R.M.S. Newfoundland from Boston to Liverpool and took the opportunity of keeping up a navigational plot using a minimum of charts and instruments. The sextant I used was a box sextant and it occurs to me that some description of this instrument may be of interest to navigators. Box sextants are lightweight and usually have a sling case which enables them to be carried or packed away easily. They are much less expensive than the standard sextant, and since they are precision-made instruments will last just as long. Good results can be obtained with them both in coastal navigation and offshore.
Modern Nautical Tables
Authors: Burton S. M.
Published: January 2010

H.M.S. Dryad's memorandum (Journal, 9, 444) speaks of ‘only those tables required’. But what this word ‘required’ does or should mean could be debated ad infinitum. The main division comes as between a set of tables intended to be an instrument of practical navigation and one intended to be an instrument of technical education, and the dividing line between the two would be a very blurred and disputable one indeed. My own set of nautical tables came into existence because I was convinced at the time that a set of tables, ‘streamlined’ for sea use was urgently needed, and in so far as logarithmic methods may be still used I still consider that my first edition was a better instrument of navigation than any of the four later ones. But whereas I knew that I wanted such a set of tables for my own use, and was of the opinion that everybody else did (or should), I became aware that I was in a comparatively minute minority. In fact it became slowly and painfully borne in upon me that something like 90 per cent of all navigators would use all their sea-going lives the tables they were first taught on. This meant that I had to consult the schools and examining authorities and include all their academic needs, and so my streamlined volume soon began to develop a corporation. I did, of course, try again with my Four-Figure Navigation Tables, but that is another story.
The Region of Collision
Authors: Sadler H. J.
Published: January 2010

Since the advent of radar, the need for correct interpretation has become only too clear from the record of so called radar-assisted collisions. The practical navigator has been shown various methods of noting PPI data and solving the problem of how best to avoid collision. We have the practical system of plotting, either with ship's head or true north upwards. We are now being offered some ingenious graphs and tables by Captain Wylie, Mr. Slater and others (Journal, 9, 161, 448). The navigator has an opportunity to study these methods and use them at sea, in clear weather, in conditions where he can assess the advantages of each method and also their accuracy.
Some Organizational Aspects of the International Geophysical Year
Authors: Day Archibald
Published: January 2010

The objects of the International Geophysical Year have been fully described in the Journal. The idea itself was first conceived in 1950 at a social gathering in the home of Professor J. A. van Allen, in Maryland, U.S.A. The small group included Professor Sydney Chapman of Great Britain and Dr. Lloyd Berkner of U.S.A., now respectively the President and Vice-President of the special committee for the International Geophysical Year. They considered that recent advances in geophysical science were such that an interval of fifty years, such as lay between the First and Second Polar years, would be too long. Moreover an interval of twenty-five years from the Second Polar Year would coincide with a period of maximum sunspot activity. Later in the same year the International Council of Scientific Unions adopted the idea and in the following year set up the special committee; at the same time the nations adhering to I.C.S.U. were invited to form national committees, of which there are now more than sixty. Their programmes make up the vast international world-wide effort. A duration of eighteen months, July 1957 to December 1958, for the Year was agreed.
Landing Forecasts for London Airport
Authors: Proctor J. D.
Published: January 2010

The weather at an airport affects the ability of an aircraft to land in so far as it controls the pilot's vision of the runway as he approaches it. This aspect of weather is at present described by (a) Runway Visual Range (RVR) as measured along the runway by Air Traffic Control, (b) Visibility as measured from and by the Meteorological Office, and (c) the amount and height above the airfield of the lowest cloud. Weather minima are specified in terms of RVR or visibility and of cloudbase by each Company for each type of aircraft using each available type of approach aid on each runway at each airport, such that an aircraft should not try to land in worse conditions. A landing forecast known as a TAF is issued regularly for each airport and specifies among other things visibility and cloudbase, giving either single values for each, or subsidiary ‘possible’ values indicating temporal variations or values with a small probability of occurrence. Examples are: ‘Visibility 10 miles TEMPO (temporarily) showers Visibility 2 miles’. ‘Fog Visibility 500 yards GRADU (gradually becoming between) 0400–0600Z mist Visibility 1 mile’. The TAF for the destination is seen by the aircraft captain before departure and during flight: if it is unfavourable he may decide to increase the fuel reserve reducing the payload or to delay departure or to divert. A wrong TAF may have costly and occasionally dangerous results.
Collision at Sea despite Radar
Authors: Wylie F. J.
Published: January 2010

The question is being asked more and more, why, despite the use of radar, collisions at sea in fog still occur. There are evidently many answers to this question and all or nearly all of them hinge on some aspect or other of human fallibility. Yet these answers may be grouped into two distinct categories, one of which covers failure to get the most out of the radar and ancillary equipment, and the other the problems of behaviour with which the radar information brings the mariner face to face in fog for the first time.
Navigation with No Aids At All
Authors: Darwin Charles
Published: January 2010

Some of the readers of the Institute's Journal may be amused at the following experiences in navigation, which I had fifteen years ago. In February 1942 I was crossing the Atlantic from Halifax N.S. to Liverpool in a convoy, and the passengers were of course never told anything about our position from day to day. I had no instruments, and not even a table of logarithms or of sines and cosines, but I did have much leisure and a good supply of blank paper, and I occupied myself by trying to find out where we were. On two occasions I told my estimates to the Chief Officer of the ship, who was not allowed to make any answer at the time, but on each occasion four or five days later he told me how far I had been from the true position.
Columbus the Seaman?
Authors: Taylor E. G. R.
Published: January 2010

Commander waters's review of Professor Morison's recent book on Columbus (Journal 10, 216) should be read in the light of the following facts, published in 1932 by the City of Genoa. They were supported by facsimiles of the documents from which they derive. The Great Discoverer was born in 1451, the son of a wool-weaver of Genoa. The family moved for a time to Savona, and were living there in 1472 when Christopher, in signing a deed, described himself as ‘a wool-worker of Genoa’. He went to Lisbon not before 1476, and while there visited Madeira to buy sugar for two Genoese merchants. He made a brief business visit to Genoa in 1479, when he said he must soon return to Lisbon. In all this there is no hint of a person who has knocked about the sea from the age often. There is no evidence that on the voyage to Guinea Columbus travelled as a sailor, while as regards the voyage to Iceland, he said it was made in February 1477, that the south of the island lay in lat. 73°N., not 63°N., and that he sailed 100 leagues (400 miles) beyond it and found that the sea was not frozen. The authenticity of this voyage may be left to the judgment of the reader.
A History of the Air Collision Problem
Authors: Roessger E.
Published: January 2010

The regulations governing visual avoidance of collision in the air and the carriage of aircraft lights were originally based on marine practice and extended to include the third dimension in aviation. These regulations were established first by the International Convention for Air Navigation and finally by the International Civil Aviation Organization.
Air Traffic Control and the Relative Position Indicator
Authors: Butler R.
Published: January 2010

The post-war development of air transport has temporarily out-paced the ability of the air traffic control service to provide for safe conduct which is always expeditious, and it has certainly out-moded the concept of visual avoidance. To alleviate the situation in the areas of high-density traffic in the United States, the Air Transport Association of America outlined a requirement for an airborne collision warning device.
The Psychological Aspects of Air Collision
Authors: Missenard A.
Published: January 2010

A thorough investigation is normally made of all the circumstances relating to an air accident. In-flight collisions can be of particular interest and should certainly be studied by doctors and psychologists. The human factor is said to play a part in 55 to 80 per cent of all accidents, and is basically psychological rather than physiological.
Two-range Decca as an Aid to Hydrography
Authors: Powell C.
Published: January 2010

The conventional Decca Navigator system is of the type in which pairs of stations generate patterns of hyperbolic position-lines. One station, the master, is common to each pair so that a chain of three stations suffices to provide the two intersecting position-lines required for fixing. Among the advantages of this arrangement are the absence of any limit to the number of users of a single chain and the compactness of the position-fixing instrument (the receiver) which can readily be installed in the smallest craft. These two features contribute considerably to the success of Decca as an aid to surveying as well as to navigation.
An Improved Hydrographic Survey Radar
Authors: Hall D. M. , Barker P. H. , Anderson N. D.
Published: January 2010

When a resurvey of New Zealand coastal waters was started by the Royal New Zealand Navy, it was realized that many areas could not be covered accurately by visual fixing of landmarks and would require accurately laid beacons. It was also known that if accurate radar ranging could be provided, then a reduction could be made in the number of beacons to be laid and in the time required for the survey. As the standard Admiralty survey radar type 972M was not available as a complete equipment the Dominion Physical Laboratory were asked to develop a radar. This paper outlines some details of the radar and the operational results after two years installation on board H.M.N.Z.S. Lachlan during the survey of Hawke Bay.
Admiral Sir Francis Beaufort
Authors: Collins K. St. B.
Published: January 2010

Rear-Admiral Sir Francis Beaufort, K.C.B., F.R.S. died on 17 December 1857. He was Hydrographer of the Navy from May 1829 to January 1855. We, in the Royal Naval Hydrographic Service, regard him as one of the greatest figures in the history of the navigational sciences, and lest you should think that opinion too highly coloured by professional and national pride I will quote a press notice which appeared in a New Orleans newspaper in 1844, fifteen years after Beaufort had assumed office as Hydrographer.
Dead Reckoning and Wind Finding Accuracy over the North Atlantic
Authors: Willis D. C.
Published: January 2010

Since the original survey by Powell, the requirement for aircraft over the Atlantic to maintain their flight-planned or recleared track has been established. The following figures covering flights made by Trans-Canada Air Lines between Canada and the U.K. during the period 8 November 1956 to 16 March 1957 are intended to provide evidence as to the accuracy of estimates necessary in recent calculations appearing in the Journal. Indications of the accuracy of navigators' found winds and of mid-Atlantic position lines are included.
The Influence of Atmospheric Conditions on Radar Performance
Authors: Saxton J. A.
Published: January 2010

The paper reviews the influence of gaseous absorption and of precipitation of various forms in the atmosphere on the performance of centimetre-wave radar equipment, special reference being made to the phenomena to be expected at a wavelength of 3 cm, in view of the wide use of this wavelength for marine navigational radar. The greatest adverse effect is caused by widespread heavy rain, which leads to serious reductions of detection range, particularly in tropical-equatorial regions. The influence of super-refraction in the atmosphere is also discussed, and it is shown how skip effects may occur at times at certain ranges.
The Use of Self-contained Range and Azimuth Measuring Apparatus to Detect Collision Courses
Authors: Morrel J. S.
Published: January 2010

Some readers of the January issue of the Journal may have noticed rather strongly discrepant statements on the subject of self-contained detection devices in the several papers on collision avoidance. For example, on page 43 Gaudillère suggests either constant bearing or constant closing speed as an indicator of impending collision between aircraft; and on pages 82–87 Whitfield and Cade suggest that ships may determine transverse velocity (and hence may identify a collision course) by using a differentiated doppler radar return. But on pages 25–26 the author of this note states that the derivatives of range and azimuth required for this use are in fact too small for successful physical measurement.
The Use of Aircrew-interpreted Devices for Preventing Collision in the Air
Authors: Calvert E. S.
Published: January 2010

In recent years the problem of preventing collision in the air has become urgent because of increased speeds and traffic densities. Some operators now install what have come to be known, perhaps optimistically, as ‘anti-collision’ lights, and at the meeting of the third Air Navigation Conference of I.C.A.O., it was suggested that one or other of these systems, or some new system, should be adopted internationally. Agreement was not reached at that meeting, and the question was discussed again by the Airworthiness Committee as an ‘exchange of views’ item in July 1958. The present memorandum was prepared mainly for the use of the representative of the United Kingdom at that discussion.
Airline Navigation in Polar Areas
Authors: Pedersen E. S.
Published: January 2010

In 1952 the first transpolar flight by a commercial aircraft was carried out. During the six years that have since passed, S.A.S. aircraft have made 1635 flights across the arctic region representing approximately 26,000 flying hours. Our experience in polar navigation has been built up first on a large number of charter flights, then on regular flights on the sub-polar route to Los Angeles, and finally on regular flights across the Arctic Ocean to Japan.
The R.C.A.F. Meridian Convergency Computer
Authors: Webb P. R.
Published: January 2010

The R.C.A.F. Meridian Convergency Computer is designed to help the navigator get the best performance out of a precision gyro which can be compensated for Earth rate, such as the N-I, the C-8, the LDG-I and the polar-path. These gyros are characterized by a low drift rate and provision is made for the effects of Earth rotation to be compensated for at the observer's latitude. Any heading set on the gyro will remain on the gyro provided the gyro remains at the same place. The only drift observed will be the random drift of the gyro itself.
I—Synthetic Training Aids in the Royal Air Force
Authors: Wilson J.
Published: January 2010

Synthetic training aids in use in the Royal Air Force today range from a sectioned miniature valve used in teaching basic electronics through a wide range of devices of increasing complexity until we reach the Victor Flight Simulator linked with an N.B.S. (Navigation and Bombing System) trainer, which rivals in complexity, and probably surpasses in cost, the famous ERNIE.
III—Training in the Use of Shipborne Radar
Authors: Swallow R. G.
Published: January 2010

Many of the problems arising out of the use of radar in poor visibility can be laid at the door of ‘incorrect appreciation’ of the information available on the PPI, coupled with the lack of timely action to avoid, if possible, a close-quarter situation. To this must be added the over-confident ship handler who has never yet been faced with a collision situation in poor visibility and who may be complacent until too late.
The Evaluation and Use of the Dectra Navigation System
Authors: Hare E. W.
Published: January 2010

Dectra is a long-range radio navigation system designed to give accurate position fixing coverage over specific areas, and in particular over long trans-oceanic crossings. The position of an aircraft or ship equipped with a Dectra receiver is continuously available in the form of dial indications relating to coordinates of a Dectra lattice, and in addition this information can be presented pictorially on a normal Decca flight log. The system is at present functioning over the North Atlantic, and flight trials have been in progress since May 1957. This paper discusses the experience gained and the results obtained in the trials.
Air Trials of the Decca Navigator System
Authors: Keeling H.
Published: January 2010

The introduction of the Mark 10 Decca promised certain advantages over existing types and it was therefore deemed expedient to examine the potentialities of the equipment, its operational accuracy and general suitability for airline operation. The Ministry of Transport and Civil Aviation in conjunction with British European Airways were subsequently involved in two series of tests which began in early 1957 and continued into 1958. These tests were designed to determine the operational suitability of the Mark 10 Decca receiver and, in addition, provide a direct comparison between the performance of Mark 10 and Mark 7 equipment. All the flights were made, by day and night, on B.E.A. routes within the cover of the English chain. Ample opportunity was afforded to study the equipment under typical service conditions.
Clarifying the Rules of the Road at Sea
Authors: Clissold P.
Published: January 2010

It may not be humanly possible to draw up a code of rules for international use which are completely comprehensive and clear in every particular. The Rules for Preventing Collisions at Sea are not, and it would be useful to know the accepted interpretation of doubtful points. Criticism of the Rules is not here intended, and all references to the impact of radar upon their interpretation is omitted, as this question is now being studied by a Working Party. Suggested correct interpretations are added in brackets.
‘The Earth but a Satellite of the Sun’
Authors: Atkinson R. d'E. , Taylor E. G. R.
Published: January 2010

I Have read Professor Taylor's article with great enjoyment. There are, however, two matters of fact on which, though they do not affect her main thesis, the record should, I think, be set right, (a) The earliest experimental proof of the Earth's revolution round the Sun was neither Bessel's detection of the relative parallax of 61 Cygni, nor Henderson's determination of the absolute parallax of α Centauri (both of which occurred in 1838) but Bradley's very beautiful discovery of aberration in 1725, together with his slightly later explanation. The discovery was made in a deliberate search for parallaxes; and although that particular proof of the Earth's movement was not then achieved, it was at once recognized that aberration provided a different and equally cogent one. Bradley's work was indeed resisted, in some quarters and for a short while, for reasons which Professor Taylor will by no means find unexpected. His later discovery of one term in the nutation was also a discovery of something which would have embarrassed Ptolemy, and delighted Newton; it certainly tended to confirm the picture, if that were needed. By the time parallaxes actually were discovered, though there still were individuals, sometimes of high rank, whose prejudices were stronger than their intellects, the only point of genuine doubt was the question how far away the nearest stars really were.
Blind Landing
Authors: Charnley W. J.
Published: January 2010

A description is given of the basic principles and method of operation of a single-channel automatic blind landing system developed by the Blind Landing Experimental Unit. The system uses the internationally accepted radio aid ILS for approach guidance to the point where more accurate information is required and then two new guidance elements, magnetic leader cable and radio altimeter, are introduced for the final landing. One of the great advantages of the system is its flexibility and if new guidance elements are developed the system will be easily adapted.

Extensive flight tests have been made in all weathers and the performance achieved is much better than that obtained in manual landings in good visibility.

In considering the application of the system to civil aviation the outstanding problem Is that of safety and reliability. Various suggestions are discussed briefly and the possible requirement for an independent pictorial monitor is mentioned. Early thoughts on a monitoring system are described.
Electronic Sector-scanning Asdic
Authors: Tucker D. G.
Published: January 2010

A new system of electronic scanning is described in which the narrow receiving beam of an acoustic echo-ranging equipment (i.e. asdic) is swept over a wide sector at a very high speed. Since the transmitted pulse covers the whole sector, and the scanning is done at least once per pulse duration, an effectively instantaneous search of the sector is made without any loss of information. The results of trials at sea are shown and possible applications to surveying and navigation are briefly discussed.

The use of underwater acoustic echo-ranging systems in the form of echo-sounders (as fitted on most ships nowadays) and asdics (as used, for example, for submarine detection during the war and now applied to whale-finding and fish-finding) is well-known.1 These existing systems use a single beam of acoustic energy, the pulse being transmitted by a transducer (or loudspeaker), and received, after reflection from the sea-bottom or whale or other object, by the same or a different transducer (this time used as a microphone). The time difference between transmitted and received pulses measures the range of the bottom or object, and is recorded on a chart by a stylus moving at a speed equal to the velocity of sound in water multiplied by the ratio of the width of the chart to twice the maximum range of detection. The transmission of the pulse marks the left-hand edge of the paper, and any echo received causes a mark at a point in the stylus sweep corresponding to the range of the object causing the echo. The paper is meanwhile moving at right angles to the stylus sweep, so that the next pulse transmission marks on a line adjacent to the previous one.
Navigating the ‘Small World’
Authors: Mudie Colin
Published: January 2010

Colin Mudie was navigator of the ‘Small World’ transatlantic ballooning expedition and designer and maker of the ‘gondola’ in which the voyage was completed by sea after the balloon was forced down. Besides Mudie the crew, as many will know, consisted of his wife Rosemary, Arnold Eiloart and his son Timothy.

To be the navigator of a balloon is somewhat of a contradiction, for an aerostat or balloon travels only with the wind. Once it is airborne, navigation, in the sense of controlling or directing its path or course, becomes extremely limited. It is possible to search, by ascending or descending, for a wind-stream in another direction but the wastage of gas and ballast involved makes this impracticable for a flight of any duration. It is also possible to produce some slight effect on the down-wind course of the balloon by slowing its speed by means of a drag and using the resultant wind to slew the envelope sideways. A paravane might also be used over water, but the overall effect would be unlikely to amount to more than a few degrees. In fact the only time that the balloon navigator has any real choice of direction is at take-off, when he can either go with the existing breeze or stay put. Thus it is that for the balloon navigator more than any other perhaps the greater part of the navigation is done beforehand with reference to the wind forecasts and meteorological charts.
Errors in Radar Appreciations
Authors: Wylie F. J.
Published: January 2010

Captain H. Topley in his article on radar plotting errors (11, 167) has endeavoured to simplify the arithmetic and introduce an approximate formula which will be of practical use to the navigator. He admits that his approximation has limitations and it appears to me that some danger may arise from the difficulty which the non-mathematical navigator may have recognized when he has passed the point at which the formula will be safe to use. Further, Topley tends to concentrate on the errors in the estimated course and speed of the other vessel and to give rather less attention to the problem of errors in the closest position of approach (C.P.A.). The latter may be by far the most significant factor.
The Collision Regulations through a Translator's Eyes
Authors: Azad S. A.
Published: January 2010

IT is not often that the exact meaning of the Collision Regulations is the subject of a dispute in a court of law. However, a translator would be shirking his duty if he were to put the easiest interpretation upon each phrase.

The author recently attempted to translate the Collision Regulations into the Urdu language. This article presents his main findings on the subject of drafting.

Two defects recur too often to be greeted at each encounter and it would be convenient to deal with them collectively. They are:

(1) The use of unnecessary words, and

(2) The use of different words to convey the same purport.
The Early Years of the Royal Society
Authors: Jones Harold Spencer
Published: January 2010

This year the Royal Society celebrates the third centenary of its foundation. In this paper Sir Harold Spencer Jones, the late Astronomer Royal, who was the Institute's first President, describes the early years of the Society and shows how closely some of its work was related to navigation.

For some two thousand years, until well into the seventeenth century, the writings of the ancient Greek philosophers, and in particular those of Aristotle, were regarded as the supreme fountain of wisdom and the source of all knowledge. The break with the Aristotelian dogma may be said to have started with the publication by Copernicus in 1543 of his De Revolutionibus Orbium Coelestium whereby the Earth was displaced from proud position as the centre of the Universe, fixed and immovable, and asserted to be not only rotating around an axis but also to be merely one of a system of planets revolving around the Sun as a centre. Copernicus had refrained for thirty years from publishing his theory as he knew that it would be received with ridicule, not merely because it was not in accordance with Aristotelian dogma but also because it would be held to be against the Scriptures. The Copernican theory met, in fact, with widespread opposition and more than a century elapsed before it came to be generally accepted; for long it was regarded as merely a convenient mathematical representation of the motions of the planets without any true physical basis.
Notes on the Research and Development Programme of the U.S. Federal Aviation Agency
Authors: Giesecke Hans
Published: January 2010

The expansion of air traffic in the United States continues at a forceful rate and shows no signs of decelleration. The Federal Aviation Agency (F.A.A.) traffic control statistics of Fig. 1 show total yearly operations and their relative growth. The graphs distinguish between the three major airspace users, i.e. the scheduled air carriers, the military activity at F.A.A. controlled airfields, and general aviation. The term ‘general aviation’ combines all non-military and non-scheduled airline operators, such as business fliers and private individuals who operate their own airplanes. In addition to the total trend the most significant aspect to note is the high percentage of general aviation activity and its explosive growth rate.
The Revision of the Collision Regulations
Authors: Quick J. H. , Wylie F. J.
Published: January 2010

This account of the recent International Conference on Safety of Life at Sea, has been written for the Journal jointly by Captain J. H. Quick, C.B.E., the Professional Officer and Chief Nautical Surveyor to the Ministry of Transport, who was a delegate to the conference, and Captain F. J. Wylie, R.N., the Director ofthe Radio Advisory Service of the Chamber of Shipping and Liverpool Steam Ship Owners' Association, who was an advisor to the British delegation. The account concentrates on those parts of the conference's work which will be of most interest to the seafarer, and in particular on the revision of the International Regulations for Preventing Collisions at Sea.

The Final Act of the conference, with Annexes, including the texts of the revised International Convention for the Safety of Life at Sea and revised International Collision Regulations, will be published shortly by the International Maritime Consultative Organization, from Chancery House, London.

The International Conference on the Safety of Life at Sea (1960) concluded on the 17th June. Forty-five governments had sent delegations and in addition ten other governments were represented by observers. The purpose of the conference was to revise the International Convention for the Safety of Life at Sea (1948) and the International Collision Regulations.
Navigating the Supersonic B-58
Authors: Polhemus William L.
Published: January 2010

This account of the problems of navigating the Hustler, the Convair B-j8 supersonic bomber, was presented at the sixteenth Annual General Meeting of the American Institute of Navigation, held at the United States Air Force Academy in Colorado Springs on 16, 17, 18 June. It is published with the kind permission of that Institute.

In navigating high-performance vehicles with the precision required to get acceptable results, the individual is limited in his ability to assess all the data available about heading, speed, instrument readings, &c, and to act upon this information in sufficient time to get the job done. The same limitations apply to pilots when flight conditions approach the design limits of the aircraft. For these reasons the manual tasks required of the crew of the B-58 have been automated to the extent that transition to a missile environment seems almost complete.
Fifteen Years of Marine Radar
Authors: Wylie F. J.
Published: January 2010

In this paper, by the Director of the Radio Advisory Service, a comprehensive survey i s made of all the main trends of development in commercial marine radar since it first went to sea in 1946. The opinions of a representative group of seamen on the value they get from radar is analysed, and finally some views of manufacturers and seamen on what the future may hold are examined. The paper was presented at the annual meeting of the Ausschuss fur Funkortung held in Kiel on 10, 11, 12 September 1960, and is reproduced with the kind permission of that body.

The last fifteen years represent almost exactly the whole life of commercial radar in merchant ships; in the United Kingdom the first commercial types were beginning to go to sea towards the end of 1946. The period has been an intensely interesting one from almost every aspect of the subject and the writer is fortunate in having been associated with merchant ships, and their owners, for thirteen of these fifteen years and with the subject of radar at sea since 1936.
Some Aspects of Doppler Track Computer Navigation
Authors: Webb P. R. W.
Published: January 2010

The doppler track computer is a navigation device which accepts inputs of ground-speed and track from a doppler radar, and computes and displays miles to go and miles transverse to a selected track. Several types are available on the market.

The heading input to the doppler may be from a magnetically slaved gyro or from a free gyro corrected for Earth rate. Thus, either magnetic tracks or gyro tracks are fed to the computer. Also, navigation may be carried out with reference to airways, mercator, conformal conic, oblique mercator, or polar stereographic charts.
The Calvert Methods of Manœuvring to Avoid Collision at Sea and of Radar Display
Authors: Wylie F. J.
Published: January 2010

These methods were briefly described in the Journal (Vol. 13, No. 2). They were prefaced by some comments designed to draw a comparison between the air and sea problems and collision rates. Statistics are liable to be misleading if not perfectly understood and definitive, and marine collision statistics as much as any. It should be realized that Lloyd's List figures include almost every collision incident to ships of joo tons and over and that a comparable air figure would probably need to include damage to aircraft by aircraft on airfields and in hangars and whether under their own power or in tow.
A Plotting Device for the Radar Observer
Authors: Sadler H. J.
Published: January 2010

To obtain all the available information from radar when visibility is poor, it is widely recognized that plotting is essential. No doubt plotting is carried out whenever possible, but in many merchant ships at sea today the ideal has limitations due to manning difficulties. Where the master has only one officer on the bridge to assist him it is not easy to cope with all bridge duties and carry out plotting in the usual way. To obtain full and accurate information a plotting officer must give his undivided attention to make use of the three known elements, range, bearing and own speed in order to produce the other ship's course, speed and nearest approach and follow up with the change of course and speed that may be required to keep out of the region of collision.
Navigation Using the Transit of an Artificial Satellite
Authors: Shinn D. H.
Published: January 2010

F. G. Smith describes (this Journal, 13, 109) a system for determining position from a single observation, probably lasting for a time of the order of a few minutes, of radio transmissions from an artificial Earth satellite. There are in this system two engineering difficulties which I think Dr. Smith has underestimated; these are the frequency stability and the power required. In order to establish these requirements it is necessary to consider in some detail how Dr. Smith's system would work.
French Schemes for Tidal-energy Installations
Authors: Gougenheim André
Published: January 2010

For a long time, in countries where the tides show a large rise and fall in certain waters, thought has been devoted to the exploitation of the power brought into action by this phenomenon. Anyone interested in the problem will be familiar with the names of Passamaquoddy, Cobscook, Petit-Codiac, San José and Mezen bays, and the Severn, Abervrach and Ranee estuaries. All these stretches of water have been, as some still are, the subject of investigations carried to very different stages, with a view to building barrages to hold the water brought up by the tide, and plants to collect power from its return.
Doppler Correction for Surface Movement
Authors: Grocott D. F. H.
Published: January 2010

If a radar transmitter and receiver are mounted together in the nose of an aircraft and flown at speedVover flat ground towards a vertical reflector (Fig. 1), then the received signal at the reflector differs in frequency from the transmitted signal by +V/λ (the doppler frequency), where λ is the wavelength of the transmitter. The reflected signal back to the aircraft undergoes a further increase of frequency +V/λ, thus the received signal at the aircraft differs from the transmitted frequency by + 2V/λ. This difference in frequency, referred to as the doppler shift, is proportional to the speed of the aircraft.
The Mystery of Andrea Doria
Authors: Bell F. C.
Published: January 2010

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