The problem of presenting barometric height in aircraft altimeters is discussed. The alternative methods of presenting a numerical value are outlined and their characteristics analysed with reference to available comparative evidence providing a quantitative assessment. The properties of various methods of presentation are examined with reference to the varied uses of the altimeter. The conclusions are discussed with relation to the recommendations of the U.K. Altimeter Committee.

It is concluded that no single means of presenting height information will meet all of the roles in which the altimeter is used and that the recommended solution is a combination of a digital counter presentation giving an unambiguous height value combined with a circular scale and pointer rotating once per 1000 ft. providing rate and angular cue information for control purposes. Freedom of choice in presentation can only be achieved by the use of a servo-operated display.

This paper is based mainly on a study carried out in 1976/7 for the UK Department of Industry into the long-term development of air traffic control systems in Europe by a team drawn from the Civil Aviation Authority, the Royal Signals and Radar Establishment and private industry, in which Coopers and Lybrand provided the economic expertise.

Until the early 1970s, air traffic control was almost completely neglected by air transport economists. Economists contributed to the planning of airports and airline operations but not to the third facet of the air transport system. However, in 1970–1, in conjunction with a programme of expansion and improvement of the country's airports and airways, the US Department of Transportation launched a major study of the airport and airways system. This was designed to establish an equitable charging policy between the different categories of user but in the event its recommendations in this area have only recently begun to be followed.

The purpose of this paper is to identify and discuss official British general charts of New Zealand. The principal development period of the general chart ended when the fourth chart was published in 1885; this edition was not superseded until 1964.

The problem considered in this note is that of determining an upper limit for the chance that an error will not exceed some given quantity. Where the pattern (or frequency distribution) of the errors is either known or assumed, the solution to the problem is merely a matter of calculation. This note starts by making the minimum assumptions about the pattern of errors, and then examines the effect of gradually increasing the restrictive assumptions.

A recent oceanographic cruise of the Spanish research vessel, B. O. Cornide de Saavedra, provided a suitable platform from which to survey ship traffic through the strait of Gibraltar covering several days. This was long enough for a representative sample to be taken, 472 ships. It was observed that only 65 per cent of the ships passing through the strait observed the traffic lanes. The current structure of the Alboran Sea may offer economic advantage to a different traffic convention. The present mean traffic is 5·8 ships per hour which represents a density greater than that of the Strait of Dover. This suggests that traffic regulation, in the interests of preventing loss of life and oil spills, may be necessary in the near future, particularly when the Suez Canal has been opened to larger tankers.

Heading errors caused by gyroscope drift affect the positioning precision of pedestrian dead reckoning, and these errors are even greater for smartphone-based reckoning. In this study, an optimised improved heuristic drift elimination (O-iHDE) method is proposed to correct the heading errors on a smartphone gyroscope. Based on an analysis of the improved heuristic drift elimination (iHDE) and enhanced improved heuristic drift elimination (E-iHDE) algorithms, the quaternion method is used to update the attitude and angle threshold judgement conditions, and a method for correcting the quaternion is added to eliminate the heading errors caused by random gyro errors. The analysis of multiple sets of experiments shows that the new method improves the ability to discern and correct the walking route, and the heading accuracy is improved by more than 90%, which extends the effective operation time of pedestrian dead reckoning positioning based on the step-by-step system.

With reference to Captain Emden's paper in the April 1975 issue of this Journal, in which he refers to the control and identification of shipping passing through the English Channel, and the numerous articles by Captain Wylie on the subject of computerized shipborne collision avoidance systems, why not adapt the ship-borne radar systems for land based control of Channel traffic ? A modified shore based system would, with present and predicted traffic movement, be ideally suited to this type of application. As to the problem of operator traffic identification and control, the present civil air traffic control procedures would seem to provide the ideal solution; if all shipping were required to carry dual channel multi-code transponders in addition to the current obligatory navaids.

The Eva G. R. Taylor Lecture is jointly sponsored by the Institute with the Royal Geographical Society, the Hakluyt Society and the Society for Nautical Research to enable a lecture to be given every year by a distinguished scholar in one or other of the branches of knowledge to which Professor Taylor made such notable contributions. The 1999 lecture was presented at a meeting held at the Royal Geographical Society on 30 November 1999. Michael Richey first describes the events leading up to the dramatic announcement by Yale University in 1974 that the famous Vinland Map it had acquired some nine years before might well be a fake; and then the steps taken to try to rehabilitate it. Professor Taylor was almost certainly the first scholar to set down in detail the reasons for believing the map to be a forgery. The map remains a mystery, for while the evidence seems for the most part to point towards forgery, who by and when and why remain in the air. Michael Richey is a Gold Medallist and a former Director of the Institute.

In the near future, Spaced-Based Augmentation Systems (such as the Wide Area Augmentation System in North America) will become operational, permitting the use of GPS as a primary system for all phases of flight. Recently the International Civil Aviation Organisation (ICAO) has recommended the use of un-augmented GPS as a supplemental navigation system for all phases of flight including non-precision approaches. In this paper, the salient features of the Air Traffic Control (ATC) system in India, and the use of conventional navigational aids are described. A new landing procedure is proposed using un-augmented GPS known as ‘a non-precision instrument approach procedure with vertical guidance (IPV)’ for Hyderabad Airport, Runway 27. This procedure, if implemented, would be cost-effective and reliable for many airports in India. An algorithm has also been developed for determining the range and bearing between the departure and the arrival waypoints of an aircraft using the IPV.

Recent statistics are reviewed with regard to deficiencies in standards of seaworthiness often resulting in detention as noted from surveys worldwide. Recent ship loss statistics are analysed, the subject of ownership of Flag of Convenience (FOC) vessels is addressed and FOC registry related to vessel loss data. The increasing age of the world fleets is noted as replacement orders for new hulls have dwindled. Crew costs are discussed and considered in relation to economics and safety of operation. Comparison is made on ship safety between routed and non-routed vessels. Improvements in weather routeing services and safety are noted as a result of employing automated systems.

The new Australian ship reporting system, identifier ‘REEFREP’, will be the core component of a Vessel Traffic Information Service (VTIS) covering the Torres Strait region and the Great Barrier Reef (GBR). It is the first such system to be considered by the International Maritime Organization (IMO) under the terms of the new SOLAS 74 regulation v/8-1, which entered into force on 1 January 1996 and allows for ship reporting systems adopted by the Organization to be made mandatory for all, or certain categories of vessels.

The REEFREP system, planned for implementation on 1 January 1997, extends for some 900 n.m. or about 1500 km along the Queensland coastline. It will be a VHF radio-based system with radars covering three selected focal points in the Torres Strait, off Cairns and in the southern approaches to the inner route. The system will provide a capability for a single Ship Reporting Centre to interact with shipping, enabling the provision of improved information on the presence, movements and patterns of shipping in the area and the ability to respond more quickly to an incident or pollution should this occur.

An interesting feature and a major factor in the system design is the remoteness of most equipment sites and the limited infrastructure available to support communications and data transmission requiring the application of advanced technology and video transmission, solar power generation and software engineering skills of a high order.

This paper discusses the development of Electronic Chart Display and Information Systems (ECDIS) and Electronic Chart Systems (ECS) generally. The role of ECDIS and its implementation is also discussed and compared with the trend by manufacturers to the alternative ECS. International developments in relation to ECDIS and ECS initiatives are looked at briefly and a view on the relationship between government and commercial organizations is presented with reference to the safety of navigation.

This paper, and the following paper, were presented at the 8th Congress of the International Association of Institutes of Navigation held in Beijing, 6–11 September 1994.

Delays in the terminal area lead to increases in the operating cost of the aircraft involved. We assess these costs as one criterion of the effectiveness of the air traffic system in the terminal area, and to give a measure of the desirable expenditure on methods of reducing delay (e.g. improved radar, additional runways or even an extra airport). This note discusses methods of assessing the cost penalty of delays exclusively to the airline operator and gives examples for three types of aircraft, a short-range subsonic jet, a long-range subsonic jet and a supersonic transport.

Terminal area delays occur essentially because aircraft apply for use of the runway, either for take-off or landing, in a random fashion and because the acceptance rate of the runway is limited by the need to maintain safe separation between aircraft on and in the vicinity of the runway. Such delays involve penalty to the aircraft operator in terms of extra time and fuel consumed and hence of extra operating cost.

It is not often that a drama of the sea provides the main story in the news, and it is still more unusual for such an occurrence to continue to occupy the headlines; but the Torrey Canyon disaster was unique in having done this for a whole month and more. Day after day, there was a slow and inexorable increase in the area affected by the catastrophe and in its duration: while such protective measures as could be improvised could seldom do more than repair damage that it was impossible to prevent.

In 1965, following the Eastbourne Conference, the British, French and German Institutes of Navigation formed a Working Group to make a study of the environment in which the supersonic transport will operate and of its implications for the navigation of such aircraft. The Group's initial task has been one of education, largely through discussion of a series of papers submitted to it. Some of the papers considered have already been published in the Journal (Vol. 19) and a further selection is published below. Table I was contributed by Mr. G. E. Beck. The illustrations to these papers have not all been reproduced.

1. Atmospheric Conditions. It will be useful to distinguish between different kinds of atmospheric influences on supersonic aircraft operations. They may be classed as follows:

(a) Sporadic effects near the ground

(b) Sporadic effects in the free atmosphere

(c) Effects on sonic boom

(d) Effects of atmospheric ozone

(e) Permanently effective atmospheric parameters, such as temperature, density and wind.

In 1961 the Institutes of Navigation in Great Britain and France, with the Deutsche Gesellschaft für Ortung und Navigation, formed a representative Working Group to go into the question of regulating traffic in converging areas at sea with particular reference to the Dover Strait. The Group's Report, which was published in October 1962, made certain proposals for routing traffic in the area which were accepted, in April 1964, by the Maritime Safety Committee of the Inter-Governmental Maritime Consultative Organization.

The Loran C radio position-fixing system has been described in technical detail at international conferences and elsewhere. This paper tries to convey the general ‘feel’ of the system and its characteristics and to indicate, with as few irrelevancies as possible, what sort of process makes the two readout counters go round and give the navigator his position fix. The equipment to which the paper refers is the AN/SPN-31 marine Loran C receiver, which was designed and produced by Decca to a U.S. Bureau of Ships specification. Individual makes of Loran C set differ in various ways, but SPN-31 will serve for illustrative purposes.

1. Hovercraft Environment. With the exception of the sidewall craft which is unlikely to achieve speeds in excess of 30 knots, all hovercraft depend on their ability to rise clear and free from water drag in order to achieve their high economical speeds. Nevertheless a hovercraft will tend to conform with the surface over which it is travelling. A rough sea produces a rough ride which at speed produces a motion not unlike that of a car going over a series of hump bridges with vertical accelerations in the order of 1½ g—one needs to be strapped into a seat. The most efficient means of propulsion is achieved by using air screws; these are noisy and necessitate crew members using an intercom. Control surfaces, rudder and airscrews are aerodynamic and to reduce air drag the hovercraft is likely to be low in silhouette and give poor all-round vision to the command. The biggest single factor is drift; being aerodynamic and free of water drag, the hovercraft is completely wind borne and in moderate beam winds can track with as much as 45° of drift angle on and turns out of wind can be alarmingly large.