Forty years ago Sir Harold Spencer Jones, Astronomer Royal, gave the first Presidential Address on the ‘Development of Navigation’ so it seems appropriate on this anniversary to address a related theme from a different perspective.

It was on the river Rhine that radar started its inland waterway career, followed almost immediately by the inland waterways in the Netherlands. In those days the inland waterway fleet was composed of ships owned by a few large companies and ships owned by their skippers.

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development period of the general chart ended when the fourth chart was published in 1885; this edition was not superseded until 1964.

On ne sait pas pourquoi ils s'echouent parfois sur la plage; car on assure qu'ils le font assez souvent, quand la fantaisie leur en prend, et sans aucune cause appréciable.

This paper represents a follow-up of work previously reported at an Ordinary Meeting of the Institute and published in the Journal in May 1986 under the title ‘Navigational Aspects of JTIDS’.

Technical studies on JTIDS for the airborne applications are being directed by the Royal Aircraft Establishment (RAE), Farnborough and by the Admiralty Research Establishment (ARE), Portsdown, for maritime use, for which Systems Designers Scientific is providing technical support in a number of areas. One such field is Relative Navigation (relnav). As part of this MOD-funded work a relnav simulator has been developed at the RAE. This simulator is currently in use for the assessment of the relnav capability and has been used to produce the results presented in following sections.

This report gives a brief description of JTIDS relnav and presents some basic features of relnav performance in simple communities. Then a description of relnav performance in fragmented and loosely coupled communities is presented. Finally a brief summary of the main points and conclusions is given.

This is an abstract of a paper commissioned by the Lights Advisory Committee and published in June 1987.

The aim of this paper is to provide a collective overview of current state-of-the-art weather routeing and it is therefore intended to give a descriptive appraisal. Essentially the paper will concentrate upon the vessel route optimization procedures, data-handling techniques including the parameters necessary to implement the methods, the ship-resistance characteristics and the James speed performance curves.

In this paper a mathematical model is presented to explain the phenomenon of yawing oscillations of a ship, when sailing in a mean straight course with a constant mean speed. With this model, periodic yawing can be simulated as a result of simultaneous periodic rolling and pitching, emphatically without the input of any rudder action. Additionally, the study throws a new light on the old question of whether the Cardan suspension of the compass bowl should be with the outer gimbal axes fore and aft or athwartships.

Potential points of collision (PPC) and predicted areas of danger (PAD) are used in marine radars for assessment of risk of collision and of action to avoid collision. Both are useful concepts for automatic radar plotting aids (ARPA) which lead to a better understanding of collision avoidance. The PAD display, developed by Sperry Ltd, is a graphic form3 alternative to the vector display. More information can be obtained from the PAD display than from the vector display but additional knowledge is necessary for the mariner to correctly interpret and use the information. The IMO Resolution on ARPA Performance Standards emphasizes the need for deck officers to understand the basic principles involved in the use of the equipment. In this paper consideration will be given to the information obtained from the PAD display and a suggestion will be made for possible improvement of the shape of the PAD.