There is no generally accepted definition of the difference between a map and a chart. A widespread feeling probably exists favouring the old saying that maps are to look at and charts to work on. It is true that the term ‘aeronautical chart’ gained a general currency over alternative terms as contact flying gave way to aerial navigation. But, in this paper, the terms ‘map’ and ‘chart’ will be used as seems appropriate to each occasion, without attempt to conform to any particular definition.

We can get an idea of what was available to the earliest aviators by looking at an Ordnance Survey reprint of one of their nineteenth century maps (Fig. 1). They are printed in one colour only, black on white. By far the predominant feature is the hill shading. Quite gentle hills are hachured with a heaviness which tends to obscure both natural features like rivers, lakes and woodlands and man-made constructions such as towns and villages, roads, canals and railways. Hills are, of course, very important features to those on the ground, since they limit the extent to which other features can be seen. To the soldier, the significance of high ground is self-evident, and it was principally for the ordnance requirements of soldiers that these maps had been developed. But when men began to view the ground from the air, the perspective changed. Hills appeared flattened out and, provided that you knew the height of the tallest in the area and were sure none would impede your take-off or landing, were of minor significance. Lakes and woods, though, were spread out before you in their distinctive shapes, while railway lines and canals presented bold straight lines and curves, and rivers their unique courses, to your view. The need was for new kinds of maps which would give due prominence to such features.

The 2007 Annual General Meeting of the Royal Institute of Navigation was particularly significant; not only did it celebrate the 60th anniversary of the founding, but also celebrated the granting of the Royal Charter of Incorporation to the Institute by Her Majesty Queen Elizabeth II. Our President, Professor David Last, marked the occasion with his Presidential Address which is recorded here.

This paper describes three different antenna systems for mobile vehicle applications. The antennas are either patches or derivatives in all cases. The first is a dual-band telephone antenna with a low profile and wide bandwidth. Operating at 900 MHz and 1800 MHz, with a VSWR of better than 1·7, it is a hybrid construction combining a monopole with a top-loading patch shorted to the ground-plane. Extra-shorted pins provide the upper frequency band coverage. It provides monopole radiation characteristics and can be hidden under a plastic panel or mounted on the vehicle roof. The second is a microstrip patch antenna integrated into a laminated glass windscreen for a vehicle. It is fed using a coplanar waveguide feed printed on the innermost layer of the glass, avoiding the need for a contacting feed within the laminate. The patch and ground plane are meshed for manufacturing in the glass to avoid distorting the heat profile when the glass is shaped and laminated. The patch is easily fed from inside the vehicle and is potentially a very low cost design. The final antenna discussed is a dual-band patch antenna specifically designed for the Globalstar satellite telephone system at 1·6 GHz and 2·45 GHz. It also covers the Iridium band at 1·6 GHz. A single circularly polarised patch is used. Dual-band operation results from truncating the corners of the square patch and judiciously placed slots to achieve a band spacing of 1·5.

In a car navigation system the conventional information used to guide drivers in selecting their driving routes typically considers only one criterion, usually the Shortest Distance Path (SDP). However, drivers may apply multiple criteria to decide their driving routes. In this paper, possible route selection criteria together with a Multi Objective Path Optimisation (MOPO) model and algorithms for solving the MOPO problem are proposed. Three types of decision criteria were used to present the characteristics of the proposed model. They relate to the cumulative SDP, passed intersections (Least Node Path – LNP) and number of turns (Minimum Turn Path – MTP). A two-step technique which incorporates shortest path algorithms for solving the MOPO problem was tested. To demonstrate the advantage that the MOPO model provides drivers to assist in route selection, several empirical studies were conducted using two real road networks with different roadway types. With the aid of a Geographic Information System (GIS), drivers can easily and quickly obtain the optimal paths of the MOPO problem, despite the fact that these paths are highly complex and difficult to solve manually.

One of the essentials of the Collision Regulations is that they should, so far as possible, eliminate doubt in the minds of navigators using them. In recent years, an amendment has introduced a serious, dangerous doubt.

A dynamic state realization for tightly coupling Global Positioning System (GPS) measurements with an Inertial Navigation System (INS) is described. The realization, based on the direct fusion of GPS and INS systems through Kalman filter state dynamics, explicitly accounts for temporal and spatial decorrelation of GPS measurement errors (such as tropospheric, ionospheric, and multipath errors) through state augmentation, thereby ensuring Kalman filter integrity under fault-free error conditions. Predicted system performance for a Local Area Augmentation System (LAAS) aircraft precision approach application is evaluated using covariance analysis and validated with flight data.

Built-in fault detection mechanisms based on the Kalman filter innovations are also evaluated to help provide integrity under certain fault conditions. It is shown that an algorithm based on the integral of Kalman filter innovations outperforms other existing GPS fault detection methods in the detection of slowly developing ranging errors, such as those caused by ionospheric and tropospheric anomalies.

In order to analyse quantitative radar observations of bird movements, one needs to know the dimensions of the air space surveyed by the radar. The present study shows how to calibrate the operational beam width and the maximum range of any radar for cross sections for different body sizes of songbirds. The trial used an X-band fan beam ship radar of 25 KW (Furuno Fr-2125) and a captive balloon. Metal spheres of different diameters, fastened to the bottom of the balloon at defined distances, corresponding to the radar cross sections of song birds, were moved in all three dimensions of the air space. Simultaneously to the location by radar, the position of the suspended sphere was measured by theodolites.

The aim of this paper is to give insight into the day-to-day navigation of a modern day cruise vessel – in this case a state of the art 77,000 GRT vessel – 261 metres long with an 8·0 metre draft, carrying 2270 passengers and 910 crew. The ship operates mainly in the Caribbean in winter and Europe – Mediterranean and Scandinavia – in the summer. The instructions are my own, which supplement the Company's (which at present do not fully cover a full Electronic Chart Display and Information System (ECDIS) operation) and have been written to ensure all Bridge Officers fully understand how I expect to operate the Bridge at sea and in confined waters using ECDIS as the main navigation system. The paper is presented in its user format and is a copy of my orders as written.

In an earlier paper, the writer attempted a quantitative study of a flow-planning system for aircraft intending to fly across Europe. This paper aims to offer each aircraft a clearance giving a reasonable expectation that, throughout cruising flight at least, there will be no conflict with other traffic. Such a clearance is sometimes termed a ‘tube of flight’. Reference i assumed a pattern of traffic flying along rhumb lines, each flight having a starting position chosen at random in a region roughly the size of Europe. Flight was in a random direction and the flight path length was chosen at random from a plausible distribution.

Following the initial development of 20-channel, all-in-view Global Navigation Satellite System (GNSS), GPS/GLONASS/Inmarsat-3, receivers at the Institute of Satellite Navigation (ISN), University of Leeds, a modification programme has been undertaken to allow real-time differential corrections to be sent from one 20-channel receiver to another identical receiver using a serial link between them. The differential correction software incorporates the RTCM SC-104 and RTCA DO-217 format developed specifically for GPS and adjusted by the ISN to allow simultaneous GLONASS operation.

After successful laboratory testing, real-time differential GNSS tests were successfully completed in static mode between Aberdeen and Leeds via the SkyFix differential data-link, and in dynamic mode at DTEO Boscombe Down using a C-band data-link between the ground and a receiver on board the DRA BAC 1–11 aircraft. The aims of the tests were, (i) to demonstrate real-time differential GNSS position-fixing, (ii) to establish the accuracy improvements brought about, and (iii) to examine the effects of data-link latency and satellite PDOP on the solution accuracy.

Dr. Freiesleben, an Honorary Member of this Institute, discusses the geometry of ellipses and hyperbolae on the sphere. These are the curves which correspond to position lines based on the constant sum or difference of distances from two fixed points. Originally applied to astronomical position lines they now have a wider application to electronic fixing systems of global coverage like Omega.

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.

The Royal Air Force has no operational aircraft fitted with Omega but the author was closely associated with two assessments of the system planned and flown by R.A.F. navigators. Both series of flights used the Marconi Elliott AD 1800 equipment. The first flights were from Boscombe Down in mid-1973; the second series, arranged by the Department of Air Warfare at the R.A.F. College, Cranwell consisted of two flights over the North Pole in September 1976.

In this paper, based on an article printed on the back of the March 1973 issue of the Pilot Chart of the North Atlantic Ocean, Mr Fricker analyses three collisions that emphasize the necessity for adhering to the concepts of prudence and safety underlying the Rules of the Road; they are no less essential when navigating by radar in reduced visibility. Terms such as ‘right rudder’, readily understood, have not been altered to conform to English Martime parlance.

Various surveys have been carried out in narrow waters throughout the world and provide data on the traffic volume, traffic density, velocity distributions of ships, &c. Although these surveys certainly contribute to the safety of local navigation they do not give any information on traffic movements between terminal points in a marine traffic system. There are a few papers on voyage distribution based on traffic surveys, statistical reports or questionnaires to mariners and also a few based on radar observation, including one in Osaka Bay in Japan which was carried out by the traffic research group of the Kobe University of Mercantile Marine and Nautical Technical College.

This address by the Secretary-General of Imco was given at a meeting of the Institute in London on 10 March 1976, with a Vice-President, Mrs. Mary Pera, in the Chair.

IT gives me great pleasure to be here today and I should like to thank you most warmly for your kind invitation to speak on the work of the Inter-Governmental Maritime Consultative Organization, or IMCO as it is commonly called. Naturally I do not need much encouragement to talk about Imco but I consider this to be a rather special occasion, because of the long and close association between the Royal Institute of Navigation and Imco. I shall advert again and more fully to this association later.

As you know, Imco is a specialized agency of the United Nations charged with important responsibilities in the maritime field. It was established by the Convention on the Inter-Governmental Maritime Consultative Organization, adopted by the United Nations Maritime Conference held in Geneva in 1948. Imco began life in January 1959 and its Headquarters have been in London from that time.

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.