bluuebunny/crossref_metadata_2025 huggingface dataset:
British Airways ETOPS Flight Planning System
Authors: Moore P. E.
Published: October 2009

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.
Ordnance Survey Digital Data for Navigation
Authors: Watts P. A. G.
Published: October 2009

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.
Catharsis: The New Jester's Transatlantic Passage, 1992
Authors: Richey Michael
Published: October 2009

Jester, in the course of her fourteenth transatlantic crossing, was abandoned on 15 July 1988 in position 39° 08′ N., 58° 43′ W., some 470 nautical miles southeast of Halifax, NS. The circumstances leading up to this melancholy event were described in an article I wrote for the Journal, which also gave, I believe, some indication of the distress the loss of the boat had caused me. Jester had been knocked down in a storm with the loss of one of her side hatches which left her open to the seas and led me to believe I would require assistance to sail on. I sent out a distress call, an act that culminated in the coastguard rescue services urging me, in view of the deteriorating weather situation, to abandon the voyage and take passage in the ship that had come to my assistance. I finally concurred but later, when the boat was lost under tow, reflected bitterly that in the circumstances the coastguard's advice could scarcely have been otherwise and that in any case the safest course is not always the right one to take. From then on, like Conrad's Lord Jim (not the most sympathetic of his characters), I was assailed by doubts.
Precision Aircraft Height Estimation with Horizontal Axis Marine Radars: (The Dual Autonomous Monitoring System (DAMS))
Authors: ten Have J. M.
Published: October 2009

Civil aviation authorities have a requirement for the application of devices which are capable of determining the geometric height of aircraft above flight level 290 with a high degree of precision. These devices, called height monitoring units (HMUS), should pave the way for a safe and expeditious introduction of reduced vertical separation of 1000 ft above flight level 290.

In this paper the design philosophy as well as the prototype development of such a device, which is called the dual-synchronized autonomous monitoring system (DAMS), are outlined. This device operates fully independently of any airborne equipment such as secondary surveillance radar transponders.

The configuration basically consists of two standard marine radars with both axes of revolution situated in a horizontal plane. With this configuration it is possible to determine the trajectory of an aircraft and, in particular, the geometrical height above ground level within typical radar slant range coverage of some 18 km. The basic application of this equipment will be in the field of height monitoring of aircraft targets in environments with reduced vertical separation standards of 1000 ft above flight level 290, but a wider application of this concept is foreseen for local precision tracking of aircraft targets.
A Note on the use of the Global Positioning System (GPS) for the Identification of Marine Radar Contacts
Authors: Stawell W. B.
Published: October 2009

The Global Positioning System (GPS) is a cheap, accurate (±100 m), satellite-based position fixing system. These qualities suggest that it might be used in the identification of marine radar targets. The first application of such a system on any scale will probably be as part of a Vessel Traffic Service (VTS) and here GPS would seem to be ideally suited. Vessels entering the VTS control zone would need to be fitted with GPS interfaced with either a dedicated VHF receiver or a ‘guard’ channel on their normal receiver A VTS radar operator needing to identify an echo would work out the echo's position from the radar range and bearing and transmit that position as the interrogating signal. Only the vessel in the control zone with that position (derived from its GPS interface) would respond with its identity. There would thus be no possibility of interference between responses or garbling that can be a problem in interrogation systems based on secondary radar. Even if the VTS had several radars, these could easily be synchronized to prevent simultaneous interrogations. However, outside VTS zones there is a clear need for a universal identification system that would allow any ship to identify any other. It would be unfortunate and wasteful if a system developed for VTS was found to be unsuitable for this general application. This note will therefore discuss the adequacy of GPS as the basis of a universal marine identification system.
Authenticity and Verification of Aeronautical Data
Authors: Reid Ken
Published: October 2009

Aviation is becoming more and more reliant on information held in electronic databases for flight planning and for en route navigation use whilst airborne. Twenty or more years ago, aircraft were flight-planned along canned routes developed by specialist navigation departments with information derived from charts, flight guides and from the source Aeronautical Information Publications, the AIPS, themselves. The data was then output in the form of a paper flight plan. The move toward computerization occurred in the mid 1970s and the early systems relied on the construction of waypoint to waypoint routes. Today, aircraft are planned to fly on canned or random routes based on airway to airway segments dependent on characteristics derived from an aeronautical database. Though correlation with paper data exists, the industry has moved a significant way along the path to database dependence for ground-based flight planning. Moreover, the move towards reliance is not limited to the ground alone for, in the case of British Airways at least, all aircraft are equipped with some form of electronic navigation database. Few airlines, if any, with the notable exception of Swissair, have invested in the creation of a comprehensive global navigation database. The costs of creating, maintaining and verifying such a product are more than even large and relatively successful airlines are willing to pay. Instead, they buy in the required ground and air systems products from Jeppesen, Swissair, Racal and the rest. They procure a service secure in the knowledge that the data has been collated, verified and authenticated before publication and use. However, is this reliance misplaced perhaps?
Monitoring the Integrity of GNSS
Authors: Ward N.
Published: October 2009

The purpose of the study on which this paper is based was to establish whether there was a maritime requirement for a Global Navigation Satellite System (GNSS) integrity monitoring and warning service in UK and Irish waters, and, if so, how best it could be established and operated.

The scope of the study extended to all maritime users: merchant ships; fishing vessels; pleasure craft; and all aspects of the voyage: harbour/harbour approach; coastal and ocean passage.

It has been assumed that the United States Global Positioning System (GPS) would be the system adopted, since it is the closest to an operational state. However, most of the technical considerations would apply equally to the Russian GLONASS or any future replacement system under international control.

The views expressed are those of the author, and should not be taken to represent the policies of the Department of Transport or any of the other bodies mentioned.
Towards a Global Navigation System
Authors: Stratton Andrew
Published: October 2009

The objectives for a Global Navigation System (GNS) may be simply stated as the provision for all users, air, sea and land, wherever they may be on or above the surface of the globe, or beneath the sea, with the navigation means of going about their business in a safe and economic manner.
Conflicts in Inshore Waters
Authors: Booth P. S.
Published: October 2009

My background is that of a professional navigator but, although I have spent a lifetime at sea, my experience as a harbour master gathering knowledge about problems in inshore waters has been limited to only the last three years. My aim is to be moderately – but deliberately – provocative in order to help stimulate discussion, though I suspect, with the strongly held views on the subject, this may not be necessary. I do not suppose there is anything new in what I am going to say and far greater minds than mine have been hard at work for many years in seeking solutions to some of the problems I will outline. Given all the diverse interests in this subject, there will perhaps never be a perfect answer but one of the important things is that the dialogue is ongoing, and embraces many organizations and authorities. This paper reflects the problems we perceive in the area of the Solent and, although some issues can be read across in general terms for other areas in the UK, the Solent is a unique area with perhaps unique problems. So what better place to start-Before I outline the scope of the problem, I must stress that the views I expound in this paper are my personal views, and should not in any way be considered official MOD policy. I would also like to say (and some readers may take issue with this by the end) that I believe my views are impartial – my main task as Queen's Harbour Master is to protect the interests of the Ministry of Defence and, once that duty is fulfilled, I have no commercial or financial axe to grind. When I look at some of the maritime safety problems, I can do so free from hindrance or pressure.
The Timing of Collision Avoidance Manoeuvres: Descriptive Mathematical Models
Authors: James M. K.
Published: October 2009

This paper examines the frequency distributions of the ranges at which vessels take action to avoid collision. Published data from simulator exercises are employed. Both give-way and stand-on vessels are considered. Lognormal distributions fitted to the data are shown to be superior to those previously published. Underlying ‘causal’ models are developed which are capable of generating the observed distributions.
Current Status of Flight Evaluation of DGPS-INS Hybrid Navigation System at NAL
Authors: Shingu H. , Murata M. , Ono T. , Ishikawa K.
Published: October 2009

This paper presents a summary of the flight evaluation of the DGPS-INS hybrid navigation system conducted at the National Aerospace Laboratory (NAL). First, the configuration of the flight experiments, including ground facilities, the measurement system, etc. is described. Secondly, the design concept for a method of estimating navigation errors using a Kalman filter is presented. Thirdly, flight profiles employed in the experiments are defined, and the experimental results of GPS, DGPS, INS, in both stand-alone and hybrid modes are shown corresponding to each profile, and the improvement of navigation performance by the introduction of the DGPS-INS hybrid navigation system is experimentally verified. Fourthly, the future plan for research on the DGPS-INS hybrid navigation system at NAL is briefly explained. Finally, it is concluded that the design concept of the DGPS-INS hybrid navigation system available for future space vehicles has been successfully completed.
The Development and Testing of Integrated Navigation Systems
Authors: Grenfell M. A. , Read J. A.
Published: October 2009

The trend in the western military towards ‘superiority through technology’ has led towards the requirement for more mobile and efficient forces and equipments to address their defence needs in an increasingly unstable and unpredictable post-‘cold war’ world.
Stabilizing the Radar Picture and ARPA Data
Authors: Berking Bernhard , Pfeiffer Joachim
Published: October 2009

Radar and ARPA are used both for anti-collision purposes and for navigational purposes. The requirements for ‘ground-stabilization for navigation’ and ‘sea-stabilization for collision-avoidance’ seem to exclude each other. Since the development of True Motion radar (TM), there is the need for an input of Own Ship's velocity. Since then, the mode of velocity input and, consequently, the mode of stabilization have been the subject of controversy. The problem became even more important by the introduction of ARPA, by the use of video map overlays and by the introduction of complex integrated navigation systems including radar.
Integration of Navigation Data
Authors: Svensson A. , Holst J.
Published: October 2009

This article treats integration of navigation data from a variety of sensors in a submarine using extended Kalman filtering in order to improve the accuracy of position, velocity and heading estimates. The problem has been restricted to planar motion. The measurement system consists of an inertial navigation system, a gyro compass, a passive log, an active log and a satellite navigation system. These subsystems are briefly described and models for the measurement errors are given.

Four different extended Kalman filters have been tested by computer simulations. The simulations distinctly show that the passive subsystems alone are insufficient to improve the estimate of the position obtained from the inertial navigation system. A log measuring the velocity relative to the ground or a position determining system are needed. The improvement depends on the accuracy of the measuring instruments, the extent of time the instrument can be used and which filter is being used. The most complex filter, which contains fourteen states, eight to describe the motion of the submarine and six to describe the measurement system, including a model of the inertial navigation system, works very well.
Navigation and Information Technology – a European Commission View
Authors: Tytgt L.
Published: October 2009

We have to welcome this initiative to bring together, during these three days of NAV94, system designers, service providers, users and administrations. We are all concerned with the need to contribute to the efficient functioning of the transport system taken as a whole, and the Ministers of Transport have underlined the contributions that can be made by satellite navigation systems and information technology.
The Current Status of the Securicor Datatrak System
Authors: Scorer Tony , Last David
Published: October 2009

Since a paper on Datatrak was presented at Warwick to the NAV90 conference, the system has improved markedly. Each of its three major components has been further developed, giving increased functionality and reliability while allowing the service to be provided at a reduced cost.
ECDIS – Its Impact Today
Authors: Riches B. A. E.
Published: October 2009

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.
The Evolution of Navigation Lights for Ships
Authors: Kemp John
Published: October 2009

The earliest record of a requirement for ships to carry lights that the author has been able to find is in the Rhodian Laws. These appear to date from about the 3rd or 2nd century B.C., and were certainly incorporated into Roman Law by A.D. 161, although Ashburner suggests that the earliest known copy dates from Byzantine times, A.D. 600–800. The Laws contain a section intended to prevent collisions between vessels under way and vessels at anchor or stopped.
Long Time-Horizons for Air Traffic Flow Planning in Europe
Authors: Ratcliffe S.
Published: October 2009

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.
GPS –An Airline User's View
Authors: Shand Andrew
Published: October 2009

This paper is intended to provide an operator's view of the impact of GPS on the air transport industry. The discussion centres on use of GPS for the en-route, oceanic, terminal area and precision approach phases of flight. In summary the author suggests the following:

(i) Inefficient use of airspace is costing the airlines a huge amount of money. However, GPS is not a pre-requisite of a move towards more efficient use of that airspace, although it will be required as part of the eventual CNS/ATM package. In the near term, better usage of current equipment such as IRS and DME, together with the introduction of ADS can provide the required level of accuracy for reduced separation in en-route and oceanic airspace.

(ii) There is a real need to provide navigation for non-precision approach worldwide, independent of ground-based infrastructure. This is the area in which GPS can provide the most immediate improvement to safety.

(iii) There are still a large number of questions hanging over GPS for precision approach. This leads the author to believe that it will not be capable of replacing ILS for the more critical Cat 2 and 3 applications quickly enough to avoid the loss of these capabilities in some critical locations. For this reason, it is postulated that MLS will be required in Europe, at least. Even if MLS is not required, there will still need to be a means of dealing with the transition away from ILS and for this reason the concept of a multi-mode receiver has been developed.
Radar Transponders and Radar Target Enhancers
Authors: Trim Richard M.
Published: October 2009

Radar transponders and radar target enhancers have been in use in a variety of applications for many years. Perhaps the most widely-known applications of radar transponders are in Identification Friend or Foe (IFF) and its civilian counterpart, secondary surveillance radar for air traffic control, and as racons in marine navigation and, most recently, as Search And Rescue Transponders (SART) in the Global Marine Distress and Safety System (GMDSS).
Safe Navigation, Ship Loss and Applications of Technology
Authors: Motte Roger
Published: October 2009

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.
Small Boat Displays: Towards Generality and Ease of Use
Authors: Bushell Peter
Published: October 2009

Electronic navigation systems are now well established on commercial vessels throughout the world. In a big ship it is entirely feasible (and probably necessary) to design the system to suit the ship. Budgets are large and there are few space constraints, so that many separate displays may be used on a bridge which would not look out of place on the USS Enterprise. This is definitely not so for a small sailing cruiser or powered leisure craft. Neither is it true for many fishing vessels. It is to those with an interest in these small boats that I address this paper.
Ordance Survey Digital Mapping for Land Navigation
Authors: Hartley Steve
Published: October 2009

The last few years have seen the launch of several new navigation-related products to the market; TrafficMaster is an excellent example of technical innovation and marketing skill which assists drivers to make decisions about travelling. There are many other products in development targeted at differing user groups for a wide range of applications.
Concorde Re-visited
Authors: Horton Peter , Moore Peter
Published: October 2009

This year marks the twentieth anniversary of the introduction of Concorde into commercial airline service. The first commercial flights were on 21 January 1976 – British Airways from Heathrow to Bahrain and Air France from Paris to Rio via Dakar. Later in that year commercial flights to Washington/Dulles began on 24 May. Services to New York were delayed until 22 November 1977. The first flight of Concorde was some seven years earlier. The prototype took off out of Toulouse on 2 March 1969 and this was followed by 002 from Filton to Fairford on 9 April. At the time it was anticipated that this was the beginning of an era when supersonic flight would be the normal way to travel long distances. Now, in 1996, Concorde is still the world's only supersonic commercial passenger airliner in airline service. This is an extraordinary achievement. The Boeing SST proved to be too ambitious and the programme was halted in 1971 after the United States Government withdrew support, while the Russian TU 144 was beset with problems. One TU 144 crashed at the Paris Air Show in 1973. The aircraft entered internal airline service in December 1975, flying supersonically between Moscow and Alma-Ata, capital of Kazakhstan, carrying mail and freight, but it did not have the range to operate viable intercontinental passenger serives. Certainly by 1985, if not many years before, the TU 144 was out of service.
Evolution of Intelligent Shipboard Piloting Systems: A Distributed System for the St Lawrence Seaway
Authors: Sudhendar H. , Grabowski Martha
Published: October 2009

Safe navigation in restricted waters continues to be a perennial concern for ship owners, operators, navigators, and citizens. The Nieuw Amsterdam, a cruise ship which ran aground in Southeast Alaska in August 1994; the Royal Majesty, another cruise ship which ran aground 10 miles east of Nantucket Island in June 1995; and the Regent Star, which caught fire in Prince William Sound, Alaska on 22 July, 1995, are just a few of the recent incidents which remind us of the importance of safe navigation in restricted waters. Clearly, the Braer, the World Prodigy, and the Exxon Valdez provide other examples of the importance of safe navigation in close waters. Fire, collision, allisions and groundings can result if vessels navigating in such waters stray.
Neuro-Fuzzy Techniques Applied to a Ship Autopilot Design
Authors: Sutton Robert , Taylor Stephen D. H. , Roberts Geoffrey N.
Published: October 2009

This paper is concerned with an investigation into the use of artificial neural networks in the design of fuzzy autopilots for controlling the yaw dynamics of a modern Royal Navy warship model. Results are presented to show the viability of such an approach and that effective designs can be produced.
Concept of Potential Area of Water as an Index for Risk Assessment in Ship Handling
Authors: Inoue Kinzo
Published: October 2009

As can be seen by the examples given below, design and planning problems related to ship-handling techniques increasingly rely on the use of ship-handling simulators.(i) Design and planning of port and harbour facilities with respect to the layout and dimensions of channels, turning basins, breakwaters, jetties, etc.(ii) Assessment of the ship manoeuvrability required to ensure safety in given port and harbour conditions.(iii) Establishment of proper ship-handling procedures required to ensure safety under given conditions.
Advances and Test Results in Differential GPS Navigation
Authors: Denaro Robert P. , Kalafus Rudolph M.
Published: October 2009

The concept of differential GPS has been under study, test and refinement for about 10 years. Operational use of differential GPS is now practical, effective and highly reliable. Refinements to the concept of differential GPS have evolved over this period, several of which have been reported by Trimble Navigation personnel. It is now reasonable to conclude that the ‘second generation’ of differential GPS has arrived, with a collection of technical improvements and features that make its use even more accurate, robust and reliable.
The IMO Worldwide Navigation Study
Authors: Griffiths P. F. C.
Published: October 2009

In 1983, the Netherlands proposed to the International Maritime Organization (IMO) at the 48th Session of the Maritime Safety Committee (MSC) that the Organization should place on the work programme a study of a worldwide satellite navigation system for marine use.
Air Navigation Systems: Chapter 2. Heading References 1909–1959
Authors: Williams J. E. D.
Published: October 2009

This paper is the second chapter of a series on Air Navigation Systems during the fifty years from the early oceanic flights and the inception of commercial aviation to the introduction of INS in civil aircraft. These papers are intended as critical commentaries. A definitive history has yet to be written. The writer would be grateful to receive criticisms of the paper or comments on the subject.
Some Human Factors Aspects of Single Manning
Authors: Hopkin V. David
Published: October 2009

In many aviation and nautical contexts, single manning is common. Some aircraft and some vessels are designed for single manning with no choice. Others can have multiple or single manning, usually depending on such factors as operational requirements, mission objectives, intended human roles, task demands, workload, envisaged mission duration, and environmental conditions.
Decision Support to Masters, Mates on Watch, and Pilots: The Piloting Expert System
Authors: Grabowski Martha
Published: October 2009

Piloting large vessels in increasingly congested waterways is no simple task. As in many ‘decision-making under uncertainty’ scenarios, masters, mates and pilots engaged in piloting are inundated with much information and required to make crucial decisions in real time. Piloting is also an inherently judgmental activity. Pilots and ships' captains invariably develop heuristics for transiting particular waterways. As vessels become larger, cargoes more hazardous, and the waterways more congested, decision aid technology is being considered to improve piloting decision-making. This paper describes one approach to providing improved on-board decision support to masters, mates on watch, and pilots navigating in restricted waters. We discuss (1) the use of cognitive decision aids in piloting, (2) the design of such a decision aid developed for New York harbour, (3) simulator experiments evaluating the expert system, and (4) plans to apply the approach and ‘lessons learned’ to the development of an expert system for tankers transiting the Gulf of Alaska.
Hydrographic Contributions to Safety at Sea 1975–85
Authors: Newson D. W.
Published: October 2009

1. ENVIRONMENTAL FACTORS. Since 1975 the inadequacy of knowledge of the depth and shape of the seabed on the continental shelves has become increasingly apparent, as navigational safety has been pushed to further limits in response to economic factors. Less than half of the British continental shelf, defined approximately by the 200 m depth contour, has been surveyed by echo-sounder and only a small proportion to full modern standards. There are inevitably many natural hazards still to be discovered. Inadequate knowledge can have particularly serious effects in heavily trafficked shallow areas, where patches of the seabed may show instability in the form of mobile sandwaves. Seabed wrecks and obstructions, some of them wartime relics, are another problem; thanks to the use of modern sidescan sonar, in 10 years the number of wrecks in the UK area databank has risen from 14000 to 22000.
Towards Intelligent Ships in Marine Training Simulators
Authors: Colley B. A. , Curtis R. G. , Stockel C. T.
Published: October 2009

An application of the model to manoeuvre ships based on the range to domain over range rate (RDRR) concept is described. A simulation of a training simulator has been set up on which the target ships manoeuvre by the RDRR model in response to mariner controlled ships. Results of experiments show that the RDRR model manoeuvres targets realistically. The applications are reduced instructor work load and increased simulator reality. The method has the potential for development to manoeuvre ships at sea.

B. A. Colley is now with Plessey Marine, R. G. Curtis is with the Department of Trade and Industry and C. T. Stockel is at Plymouth Polytechnic.
Proposed Amendments to Rule 10 of the Collision Regulations
Authors: Cockcroft A. N.
Published: October 2009

1. INTRODUCTION. At the 30th Session of the International Maritime Organization (IMO) Sub-committee on Safety of Navigation, held in July 1985, agreement was reached on some further amendments to the International Regulations for Preventing Collisions at Sea, including some amendments to the rule relating to navigation in or near traffic-separation schemes (Rule 10). These amendments will subsequently have to be approved by the Maritime Safety Committee and finally, in November 1987, by the IMO Assembly. Provided there are no objections to the proposals the amendments are likely to come into force in 1989.
Airlines and the New Technology Aircraft: A Discussion Paper
Authors: Gray G. A. C.
Published: October 2009

The aircraft referred to in the title are the Airbus Industrie A 310, the Boeing 767 and the Boeing 757. The paper has been written in conjunction with representatives from British Caledonian Airways, Britannia Airways and British Airways, airlines which are currently operating these aircraft. I am indebted to the following for their contributions: Captain Stuart Grieve (Chief Pilot, Britannia Airways), Captain Chris Norman (Britannia Airways), Captain Brian Myers, (Chief Training Captain A 310, British Caledonian Airways), Bill Grice (Chief Development Engineer Avionics, British Airways), Captain Rod Fulton (Flight Training Manager 757, British Airways) and Captain Paul Woodburn (Flight Manager Technical 757, British Airways).
Kalman Filters in Navigation Systems
Authors: Dove Michael J. , Miller Keith M.
Published: October 2009

This paper puts forward a case for more precise navigation at sea. It commences by briefly outlining existing and forthcoming navigation aids. The integration of marine navigation systems, and in particular the use of Kalman filtering is then discussed. After outlining the developments in the aerospace industries, the authors suggest why marine developments have not been so rapid as those in the air. The idea of automatic collision avoidance is also raised and a method for tracking radar targets discussed. Finally, the authors survey marine applications of Kalman filtering techniques, including some references to their own work, and assess the need for further research and development.
Calculation of the Geometry of Ship Collision Zones
Authors: Lamb W. G. P.
Published: October 2009

An account of the calculation of the geometry of collision zones surrounding vessels engaged in overtaking and meeting encounters is given. The zones are calculated for a range of mariners' decision times corresponding to clear and restricted visibility. The determination of encounter risk from the size of the zones is discussed.
Interaction of Magnetic and Stellar Cues in Migratory Orientation
Authors: Wiltschko Wolfgang , Daum-Benz Petra , Munro Ursula , Wiltschko Roswitha
Published: October 2009

This paper was presented at the RIN89 Conference on Orientation and Navigation – Birds, Humans and other Animals. The conference was held in Cardiff in 04 1989. The printed proceedings contain some 27 papers and are available by application to the Director. The price is £30 (RIN Members) or £35 (Non-Members).
Precise Positioning Systems for Mine Countermeasures
Authors: Willcocks M. W.
Published: October 2009

Accurate navigation, better described as precise positioning, is essential to efficient mine countermeasure operations. This paper will describe the basic principles of mine hunting, mine sweeping, mine classification, mine disposal and mine avoidance. The paper will describe the methods employed for precise positioning in the past, at present, and a method for the future. The sea mine has the capability of being a very cost-effective weapon, which can be deployed in peacetime for future remote-controlled activation. Events in the Red Sea and the Arabian Gulf in recent years have demonstrated that fact.
Air Navigation Systems Chapter I. Astronomical Navigation in the Air 1919–1969
Authors: Williams J. E. D.
Published: October 2009

As the marine sextant is only useful to low-flying aircraft because of its reliance on the sea horizon (see Section 1), many earlier pioneers descended almost to sea level to take their sights; but as Alcock and Brown were the first to discover, it is often necessary to climb above the cloud in order to see the sky. Some pioneers used the horizon of stratocumulus cloud below, among them K. M. Grieve who, with Hawker, would have been the first across the Atlantic if radiator trouble had not made them the first survivors of a mid-Atlantic aeroplane ditching. As Grieve was so happy with his cloud horizon, disbelief must be suspended. Indeed, what has been claimed to be ‘the first real aeronautical sextant’, designed in 1919 by the same ingenious Capt T. Y. Baker RN who invented the Baker Navigating Machine (see Section 4 5), used a reflecting prism as an index mirror and two horizon prisms giving a view of both the back and front horizons. Provided both cloud horizons were equally depressed below the true horizontal plane, the instrument gave the true altitude of the body observed.
Aspects of de Wit's Equations Governing the Apparent Spontaneous Yaw of a Ship
Authors: Flower J. O.
Published: October 2009

de Wit has produced an analysis of the apparent spontaneous yaw of a ship when undergoing combined rolling and pitching. This analysis produces a set of four first-order simultaneous differential equations which govern the motion. In de Wit the numerical solutions of these equations for a couple of representative examples are given, as well as the corresponding analytical solutions to the linearized equations. In this communication it is shown how two of the four equations can be solved analytically; these solutions can be used to obtain approximate analytical solutions to the remaining two equations.
Bacterial populations on dressed pig carcasses
Authors: Morgan I. R. , Krautil F. L. , Craven J. A.
Published: October 2009

Samples were collected at two abattoirs from four sites on pig carcasses as they were being placed in a chiller. Bacteriological examination showed that no single sampling site could be used to assess the microbiological status of pig carcass surfaces. Sampling from multiple sites on a carcass may be required to assess the degree of contamination by different bacteria. It is suggested that the hygiene of slaughtering and dressing of pig carcasses at an abattoir cannot be assessed on a single visit and that a number of visits are necessary to establish a hygiene pattern.
Seroepidemiological studies on the occurrence of common respiratory infections in paediatric student nurses and medical technology students
Authors: Gerth H.-J. , Grüner Ch. , Müller R. , Dietz K.
Published: October 2009

The occupational risk of acquiring minor respiratory infections for paediatric student nurses was estimated by performing serological examinations with influenza A, B, C, parainfluenza, mumps, respiratory syncytial virus, adenovirus andMycoplasma pneumoniaeat 6-month intervals over a period of 4 years in paediatric student nurses at two schools of nursing and students at one school of medical technology, litre increases against all tested agents occurred 1·86 times more often in the student nurses than in the medical technology students, the most frequent agents in both groups being influenza A and B. No difference in the relative distribution of the agents could be verified in the two occupational groups. Data on the protective value of pre-infectious antibody levels for influenza A, B, and coronavirus OC43 and on the importance of the spread of single agents among classmates are presented.
Shigellosis in the south-western Cape of Good Hope 1968–85
Authors: Donald P. R. , Pretorius Marie-Louise , Burger P. J.
Published: October 2009

During the period 1968–85 shigella organisms were isolated from stool specimens of 1562 patients attending Tygerberg Hospital, situated in the south-western province of the Cape of Good Hope of the Republic of South Africa.Shigella flexneri(72% of patients) was the commonest subgroup identified.Sh. sonneiwas the second-commonest isolate (20%), with smaller number ofSh. boydii(5%) andSh. dysenteriae(3%).Sh. dysenteriaehas not been isolated since 1979. In 1985 30% of isolates were resistant to ampicillin and 52% to trimethoprim-sulphamethoxazole. During this period 12 cases of shigellaemia were seen, 11 in young infants less than 13 months of age who were malnourished in 6 cases. The single adult had had a previous gastrectomy and splenectomy.
Factors affecting the toxicity of rotting carcasses containingClostridium botulinumtype C
Authors: Smith G. R. , Turner Ann
Published: October 2009

Mice killed shortly after receiving 1300–3000 spores ofClostridium botulinumtype Cper oswere incubated at one of four chosen temperatures together with bottles of cooked meat medium seeded with a similar inoculum. After incubation the rotting carcasses were homogenized. Sterile membrane filtrates of the homogenates (10–20.8%, w/v) and pure cultures were then titrated for toxicity. A temperature of 37 °C produced less toxicity in most carcasses than in cultures. At 30 °C, however, toxicity (often 2× 105to 2× 106mouse intraperitoneal LD/g or ml) was roughly similar in both systems, and some carcasses and cultures were still toxic (2× 104to 2× 105LD/g or ml) after 349 days. Surprisingly, at 23 °C, though greatly reduced in the cultures, toxicity was high in many carcasses for at least 28 days. Little or no toxin was produced in either system at 16 °C. Unfiltered homogenates (17·8–22·5%, w/v; dose 0·25 mlper os) of toxic carcasses incubated at 30 °C for 7 days invariably produced death from botulism, often within as little as 4 h, but a 1 in 10 dilution produced less than 100% mortality.
Correlation between electrophoretic types B1and B2of carboxylesterase B and host-dependent factors inEscherichia colisepticaemia
Authors: Picard B. , Goullet Ph.
Published: October 2009

Electrophoretic types B1and B2of carboxylesterase B produced by strains ofEscherichia coliisolated from 100 septicaemia cases were correlated with α-haemolysin and mannose resistant haemagglutinin (MRHA) production and with clinical data including eventual underlying diseases, origin of septicaemia and evolution. Electrophoretic type B2was phenotypically linked with α-haemolysin and MRHA production. The proportion of type B2isolates varied significantly with occurrence of an underlying illness (45% for patients without an underlying disease and 22% for compromised patients) and with the site of origin of the septicaemia (40% for those of urinary origin and 18% for infection of digestive origin). In the former infections, type B2isolates were obtained in the majority from male patients while type B1isolates predominated in women. The septicaemias associated with type B1were characterized by a lower proportion of isolates producing α-haemolysin and MRHA and by a greater frequency of septic shock and death than those associated with type B2. These facts emphasize the importance of host-dependent factors inE. colisepticaemia.
Response to foot-and-mouth disease vaccines in newborn calves. Influence of age, colostral antibodies and adjuvants
Authors: Sadir A. M. , Schudel A. A. , Laporte O. , Braun M. , Margni R. A.
Published: October 2009

Oil-emulsified (OE) and aqueous (Aq) vaccines were prepared with the same batch of inactivated A248345 foot and mouth disease virus (FMDV). Calves born to vaccinated dams did not respond to the Aq vaccine 30 or 90 days post partum. When the OE vaccine was used on a similar group of calves, no responses were elicited up to 21 days post partum. However, calves 30 or more days old responded like adult cattle to the OE vaccine. When the OE vaccine was used in colostral antibody-free calves 3–30 days old, all animals showed good antibody responses but, in calves vaccinated 3 or 7 days post partum, antibodies were detectable only after a considerable period of time. Our results show that both passively acquired colostral antibodies and age are important in the response of very young calves to FMDV oil vaccines. From a practical point of view, in endemic areas where adult cattle are periodically vaccinated, vaccination of calves between 30 and 60 days post partum with OE vaccines would lead to high levels of herd protection.
Routine surveillance data on AIDS and HIV infections in the UK: a description of the data available and their use for short-term planning
Authors: Tillett Hilary E. , Galbraith N. S. , Overton S. Elizabeth , Porter Kholoud
Published: October 2009

In the UK surveillance of AIDS and HIV infection is based on routine reporting systems. Whilst attempts are made to ensure that AIDS data are as complete as possible, numbers of reports fluctuate from month to month for reasons which are described. In 1986 there was an increase in death certificates naming AIDS as a cause of death in patients who were not identifiable in the surveillance data. More active surveillance is now undertaken in order to minimize this and other possible discrepancies.

It is probable that most cases of AIDS are reported and therefore these data can be used to describe trends in the epidemic by ‘risk group’. Laboratory reports of HIV antibody-positive tests could give an earlier indication of trends because of the long incubation period of AIDS. But these laboratory data are difficult to interpret because they represent an incomplete and biased sample of all positive persons.

AIDS cases are still being reported at a rate which is increasing approximately exponentially. Short-term predictions are presented showing a growth in the epidemic which is consistent with previously published predictions. Most cases are in the homosexual risk group. New asymptomatic homosexual patients with HIV antibody are still being identified.

The epidemic of AIDS in haemophilia patients should be of finite size although new cases of AIDS are likely to continue to be diagnosed for several years. AIDS due to blood transfusion given in the UK before donor screening appears to be a much smaller epidemic. The epidemic in drug abusers is increasing. Heterosexually acquired AIDS and HIV infections are being reported in small but increasing numbers.
Joseph Lister and Infection from the Air
Authors: Lidwell O. M.
Published: October 2009

In his book, Floating Matter of the Air, John Tyndall (Tyndall, p. 262) quotes from Robert Boyle's ‘Essay on the Pathological Part of Physik’ ‘that he who thoroughly understands the nature of ferments and fermentations shall probably … give a fair account of divers phenomena of several diseases, which will perhaps be never properly understood without an insight into the doctrine of fermentations'. It was more than a century and a half before the first part of this suggestion was fulfilled, after which the unravelling of the causes of infective diseases proceeded rapidly. In 1836 de la Tour and, almost simultaneously, Schwann (Tyndall, p. 7) discovered, in yeast, the agent of fermentation as a living organism which reproduced itself in endless succession. Schwann also observed that putrefaction in meat broth did not set in if this was kept in contact, not with ordinary air, but with air which had been previously brought to a high temperature.
Scombrotoxic fish poisoning in Britain: features of over 250 suspected incidents from 1976 to 1986
Authors: Bartholomew Barbara A. , Berry P. R. , Rodhouse Joanna C. , Gilbert R. J. , Murray C. K.
Published: October 2009

Between 1976 and 1986, 258 incidents of suspected scombrotoxic fish poisoning were reported in Britain. Histamine analysis was carried out on 240 fish samples from these incidents, and 101 were found to contain > 5 mg histamine/100 g fish. The symptoms most consistently reported were rash, diarrhoea, flushing and headache. In recent years there has been a decrease in the number of confirmed scombrotoxic outbreaks and a trend towards more sporadic incidents. Of fish samples with > 20 mg histamine/100 g, 94% were from incidents in which scombrotoxic symptoms were characteristic, but where fish had 5–20 mg/100g only 38% of incidents were clinically distinctive. Guidelines are presented based on the interpretation of quantitative histamine analysis of fish samples from scombrotoxic poisoning incidents.
Measles antibody levels in children of rural and urban areas of Nigeria following vaccination campaign
Authors: Eghafona N. O. , Odama L. E. , Emejuaiwe S. O. , Obineche E. N. , Tafida D. S.
Published: October 2009

This study compares the presence and level of measles haemagglutination inhibiting antibody in the sera of primary school children in selected rural and urban areas of Kaduna State, Nigeria following a vaccination campaign. The results, analysed by Mann-Whitney statistical test at α=0·05, showed significantly higher levels of haemagglutination inhibiting antibody in all the age groups in urban areas when compared with rural areas. The implications of these findings on measles vaccination campaigns are discussed.
Animal salmonella surveillance in Peninsular Malaysia, 1981–1985
Authors: Joseph P. G. , Sivanandan S. P. , Yee Ham Thong
Published: October 2009

During the 5-year (1981–5) surveillance period, 2322 salmonella isolations were recorded from animals and other non-human sources in Peninsular Malaysia. This was an increase of 356% over the preceding 5-year period. The 83 serotypes isolated were recovered from 41 sources. Of these 34 were new serotypes bringing the total number of serotypes isolated from non-human sources to date up 97. Food animals and edible animal products accounted for 92·2% of the total isolations, with cattle and beef accounting for 70% of the total. Salmonella dublin was the most frequently isolated serotype, whereas S. typhimurium had the widest zoological distribution. More than 80% of the non-human salmonella serotypes have also been reported in man in this country.