Back in 1914, an army surveyor who was carrying out an airborne reconnaissance of potential sites for a new military aerodrome to the west of London is alleged to have held his map upside down – and that, consequently, RAF Northolt was built to the south of what was then called the Great Central Railway Line instead of about a mile to the north-east near where South Ruislip is now. A short apocryphal story perhaps, undoubtedly distorted by the mists of history, but it serves to illustrate the need for aeronautical charts that are designed with the requirements of visual air navigation firmly in mind.

It is perhaps appropriate, on this the exact 187th anniversary of the death of Admiral Lord Nelson at Trafalgar and in the year in which so many celebrations have taken place to commemorate the 500th anniversary of Christopher Columbus's arrival somewhere in the West Indies, to consider the progress which has been made towards international co-operation and achievements in hydrographic surveying and nautical cartography, particularly since the formation of the International Hydrographic Bureau in 1921, and to look at the problems facing international hydrography in the immediate future.

This paper formed the 1993 Anderson Memorial Lecture. It was presented by the President at a meeting of the Bristol Channel Branch on Tuesday 10 March. At that time, the second Way Ahead Group (WAG 2) was still sitting. This Group has since reported to Council (see Navigation News, July/August) but the discussion of the future of the Institute is ongoing (see also the following paper).

In his Presidential Address at the 45th Annual General Meeting in October 1991, Norman Dahl gave a thought-provoking discussion of the future of the navigator. He suggested that the navigator's trade is not just a changing trade, but a vanishing one. He proposed then, and subsequently in his 1993 Anderson Memorial Lecture (reproduced as the previous paper in this issue of the Journal), that consideration should be given to the future of navigation, the future of the navigator and the future of the Institute.

In this contribution, papers and addresses over the history of the Institute are examined critically to extract insights into navigation applicable to the present era. These are used to discuss and develop the meanings of the terms ‘navigator’ and ‘navigation’.

Many animals have some kind of ‘home’ –a nest, a burrow, etc. This applies to insects that build nests and provide their larvae with food just as much as to numerous species of vertebrates. Rodents and moles are known to dig burrows; most other mammals, reptiles, amphibians and even many fresh-water fish do not roam around randomly either, but have well-defined home ranges with favourite resting places in particular cavities, under rocks or in dense thickets. Birds build nests for their young and fly out searching for food. All these animals permanently face orientation problems: they have to move swiftly and efficiently within their home range, and they must be capable of returning home when they have left their familiar area while exploring, fleeing, etc.

To both professional and amateur divers, navigation underwater in reduced visibility, or in a current or tideway, can be a daunting business. This paper explores some of the options that are available for extending or improving the diver's sensory envelope and navigational capability in such conditions, and presents some new equipment ideas that have evolved from the author's work in this field.

The North Sea is at the leading edge of offshore hydrocarbon technology due to its hostile environment and deep water. This paper gives an overview of the role of the offshore surveyor in the North Sea by discussing the survey aspects, tools and techniques used in the development of a contemporary oil/gas field. Particular attention is paid to some of the more unusual techniques being developed today.

In the former USSR, the Radionavigation Service was based on national radio systems without any real employment of foreign navigation aids. Separation of the independent sovereign States from the USSR caused problems in operating separate radionavigation systems (RNS) and resulted in failure to support the economic activity of the States with radionavigation data. Solving the problem for each new State individually seems unrealistic. Its solution can, however, be found through cooperation amongst the Commonwealth of Independent States, and the Internavigation Committee therefore suggested an initiative to coordinate these efforts via a new Radionavigation Intergovernmental Advisory Council. This suggestion was approved by the Independent States and the Council has been formed. Also, since operating the RNS in limited national interests seems inefficient, the Internavigation Committee is broadening international cooperation for the integration and joint exploitation of radionavigation systems in the interests of the world radionavigation community.

The constraints imposed by the regulatory authorities give flight crews more tasks to perform at the flight planning stage for an Extended Range Twin Operations (ETOPS) flight than for a non–ETOPS flight. Among the additional checks the flight crew has to make are the following:

(i) That the aircraft will at all times be within the distance, calculated using the still–air single engine speed for the certified time, from the nearest ‘ suitable ’ airfield.(ii) That the ETOPS planning minima, which are typically three times the Category 1 operating minima in terms of forecast cloud base and visibility, are attained for each of the ‘suitable’ airfields used.

(iii) That the weather at each of the ‘ suitable’ airfields used is forecast to be above the planning minima, not just for the time of passing, but for a period, termed the time window, from one hour before to one hour after the expected time of arrival of the aircraft at this airfield.

(iv) That there is sufficient fuel, using the most critical fuel scenario, to take the aircraft from the critical point to any ‘ suitable’ airfield used in the calculation of the route.

Europe is moving towards a more closely integrated air traffic management system through the European ATC Harmonization and Integration Programme (EATCHIP). This paper explains the need for such an approach and how it was brought about by capacity limitations in the current European air traffic system. It describes the key strategy of progressive harmonization and integration by the various States, examines the roles of the European Civil Aviation Conference (ECAC), the International Civil Aviation Organization (ICAO), EUROCONTROL and the European Commission in the management of the Air Traffic Management (ATM) development programmes. It also reviews the longer-term planning of a future system with an enhanced relationship between the air and the ground, and addresses the navigation aspects of ATM systems.

The first part of the above title was used in the Journal in 1953 for a paper by Captain Carl V. Solver. His special interest was to discover how the Norse navigators of the Viking age found their way across the North Atlantic. He was the first person to interpret the small wooden disc shown in Fig. i as a fragment of an early bearing-dial and investigations since his paper was published provide considerable supportive evidence. At the time, there was some strong opposition to his views, but he persisted with his theory and wrote a book, Vestervejen. This formed a basis for other researchers to carry his work further and, as a result, there have been many international contributions over some 40 years. The archaeological find from southern Greenland seems to show that the Norse navigator used the path of the Sun's shadow during the day as the basis of a compass.

This paper and the following three papers were presented at the EURNAV92 Conference on Digital Mapping and Navigation. This was held in London and was jointly sponsored by the RIN and the DGON. Forty-five papers were presented at the Conference and copies of the complete proceedings may be obtained from the Institute, priced at £65 for Members and £85 for Non-Members.

Approach and landing are the phases of flight most associated with accidents and near accidents, especially when external visual cues are sparse. At what is now Australia's DSTO Aeronautical Research Laboratory, research on ways of reducing the hazard incidence resulted in the development and testing of several ground-based visual approach slope indicators. The T-VASIS landing aid was an outcome of this work, T-VASIS, which has been in international use for over twenty years, is now under potential threat of displacement by PAPI which is a more recent UK development. The research which led to the implementation of T-VASIS is described here, along with subsequent events leading to the introduction of PAPI to Australia. A glossary of abbreviations is included at the end of the paper.

Since the advent of large-scale commercial aviation in the mid 1940s, a system of routes has been developed between airports serving the major conurbations of the world. To prevent collision between aircraft using these routes and off-route traffic, protection is provided to the routes and to the vicinity of airports by means of controlled airspace, airways (AWYS), control areas (CTAS) and control zones (CTRS). Zones commence at ground level and the base an area is at a defined altitude. Inside this controlled airspace certain rules apply which are more stringent than those applied outside, and all movements are subject to Air Traffic Control (ATC).

A GEC Marconi Avionics/MoD joint–funded integrated, digital terrain system called ' PENETRATE ' (passive enhanced navigation with terrain referenced avionics) is in its fourth year of flight trials on a Hunter fast–jet aircraft at the Defence Research Agency, Farnborough. Although originally designed to enable military aircraft to penetrate enemy defences at low level in poor weather conditions and at night, the system also has a direct read across to civil air transport operations. The heart of the PENETRATE system is a digital data–store housing a three–dimensional model of the terrain including cultural details, obstructions and tactical intelligence information.

PENETRATE incorporates terrain-referenced navigation to provide accurate position information relative to the ground contours. A sophisticated digital map displays navigation information and includes intelligence and intervisibility overlays. Head-up visual enhancement options are provided which can be tailored to the outside visibility. These comprise monochrome skeletal perspective displays which are superimposed on the outside world view and also on the forward-looking infra-red (FUR) scene. The display enhancements range from obstruction cues through ridge line overlays to skeletal perspective terrain presentations.

This paper covers the philosophy and architecture of PENETRATE together with details of the demonstration system. It also discusses the capability of this digital terrain system to enhance the safety of civil aircraft approaches into difficult airports such as Kathmandu and Hong Kong.

In the 1990s, digital maps are being used for a wide variety of applications. In the world of digital road maps, the most notable applications are in the area of theIntelligent Vehicle Highway Systems (IVHS). In the USA IVHS is involved with five basic interrelated applications:

(i) Advanced Traffic Management Systems.

(ii) Advanced Vehicle Control Systems.

(iii) Commercial Vehicle Operations.

(iv) Advanced Public Transportation Systems.

(v) Advanced Traveller Information Systems.

Orienteering is a navigational sport using large–scale maps (1: 15000) and a compass to locate, as quickly as possible, a series of control points in a pre–defined order. Orientation of self and map are fundamental skills in the sport of orienteering. The traditional teaching or coaching of this skill is based on a hierarchical model. This model introduces the concept of location of self by initial reference to landmarks, then routes linking individual landmarks followed by configurations of these landmarks and routes. This model quite clearly aligns with the hierarchical model of spatial reference systems suggested by Seigal & White (1975). However, it is proposed that the process-oriented model offered by Downs & Stea (1977) may be more appropriate to orienteering. The model is based on orientation and then develops through route choice, route monitoring and route recognition. Orienteering behaviour, which is based on using map and compass information to select and follow a novel route in a multi-choice route following task, appears to follow this model.

For the travelling public in the late eighties and early nineties, the most disturbing characteristic of air travel must be delays. In Europe, this is certainly the case. These delays not only cause much inconvenience to the air travellers but also generate high costs for the aircraft operators. To a large extent, these delays are due to an imbalance between the air traffic demand and the capacity of the present Air Traffic Control (ATC) system in Europe.

The AN/SSN-6 Navigation Sensor System Interface (NAVSSI) Project is a new system being designed with two primary objectives; to serve as the central distribution computer for navigation data to shipboard combat/weapon systems and to serve as the electronic chart display and information system (ECDIS). The NAVSSI will operate the digital nautical chart (DNC) database being developed by the Defense Mapping Agency (DMA). Our goal is for the digital nautical chart to replace the paper chart as a legal means of ownship navigation plotting. This paper will introduce the project and will primarily explore the use of digital nautical charts for ownship navigation with NAVSSI.

This paper, and the following 5 papers, were presented at the RIN93 Conference on “Orientation and Navigation - Birds, Humans and other Animals.” This took place in Oxford in April, and included some 40 papers. Copies of the complete Proceedings, priced £25 for RIN members and £35 for non-members, are available from the Director.