The Nineteenth Louis Blériot Lecture was given in Paris on 25th April 1966 under the auspices of L’Association Françaises des Ingénieurs et Techniciens de L’Aéronautique et L’Espace. The Lecture was attended by Sir George Gardner, KBE, CB, HonDSc, CEng, HonFRAeS, President of the Society, and Lady Gardner, by the Rt. Hon. Julian Snow, MP, Parliamentary Secretary to the Ministry of Aviation, by Mr. A. D. Baxter, MEng, CEng, FRAeS, President-Elect, Air Cdre. F. R. Banks, CB, OBE, CEng, CGIA, HonFAIAA, FRAeS, RAF (retd), Vice-President and First Louis Blériot Lecturer, Mr. S. D. Davies, BSc(Eng), CEng, FRAeS, member of Council, Dr. A. M. Ballantyne, OBE, TD, BSc, CEng, FAIAA, HonFCASI, FRAeS, Secretary, and by other members of Council and of the Aircraft Industry and by several former Louis Blériot lecturers, both English and French.

Monsieur Blum, President of AFITAE, presided at the Meeting which was attended by a large and distinguished audience. Monsieur S. Jarry, President d'Honneur, AFITAE, read the list of previous Louis Blériot Lecturers and Sir George Gardner expressed his pleasure and that of his colleagues at this reunion with their friends of AFITAE. Monsieur Blum then introduced the lecturer, Mr. Peter Masefield, Managing Director of Beagle Aircraft Ltd and Chairman of the British Airports Authority and a Past President of the Society. Mr. Masefield said a few words in French and the lecture was then read on his behalf, in French, by Monsieur Peyrelevade. A vote of thanks was proposed after the Lecture by Monsieur Potez.

The Lecture was followed by a reception and cocktail party and later by a dinner.

As the first British jet-powered aircraft was prepared for its maiden flight almost 25 years ago, the late Dr. A. A. Griffith, then Chief Scientist of Rolls-Royce Ltd, was exercising his mind on the problem of aircraft taking off and landing vertically using jet lift. The lightweight lift jet engines of compact dimensions he predicted are now being produced. Since his classic paper on VTOL to the Aeronautical Research Council in 1941 many of the difficult engineering problems have been overcome and we are now on the threshold of a most exciting era during which we shall see operational V/STOL aircraft using jet lift.

Developments in Range instrumentation for trajectory measurement over the past ten years are reviewed, and some possible future developments discussed. Instrumentation systems considered include kine-theodolites, tracking radars, multi-station Doppler systems and interferometers. Some common sources of error are discussed; it is shown that atmospheric retraction variations may be the limiting factor on the accuracy of modern trajectory measuring systems.

The most important problems during the next five years will arise from requirements for very low level weapon systems, high precision tracking of small targets with fast response characteristics and long range high precision tracking of space vehicles. Developments to meet these requirements will lead to further requirements for completely automatic data processing for the high data rates needed. It seems probable that fewer completely new instrumentation systems will be developed during the next five years, more attention being given to reducing the size of airborne transponders and other equipment and increasing the reliability and accuracy of existing equipment. Systems using a common carrier lor telemetry signals and tracking may appear.

Considerable work on isolating sources of error in existing systems and reducing them is going on and will continue. This will be combined with more advanced post-flight analysis techniques during the next five years.

The first two US/UK co-operative satellites, Ariel 1 and Ariel 2, were put into orbit in April 1962 and March 1964, and both functioned most successfully. The lecture describes the NASA Pulsed Frequency Modulated telemetry system, including the methods used to store and transmit the data to ground stations, the digitising techniques used to prepare these data for entry into a computer and, finally, the organisation of the central data handling operations to the point where the partially or wholly reduced results were handed over to the various experimenters for analysis.

The technical features of the data acquisition system used in Blue Streak flight trials are summarised briefly. The results obtained from this system, and the design modifications to which they have led, are then discussed under the heading of performance, control, structure and environment and propulsion and pressurisation.

By integration of the pressure distributions of Part I of this paper values for the normal force and centre of pressure position (or moment) are obtained herein for the three effects; interference on the body, interference on the wing, and overall body-wing. In order to estimate overall body-wing characteristics the net wing alone and body alone normal forces and centre of pressure positions are also required, methods of estimating these quantities are readily available in the literature (e.g. ref. 2). The present method gives an estimate of overall body-wing normal force which is usually accurate to within 10 per cent and an estimate tor overall cp position which is usually accurate to half a calibre. Comparison of the present method with the method of Nielsen, Kaatari and Pitts shows that there is little to choose between the two so tar as overall estimates are concerned; the present method has the advantage of an associated pressure field.

Until the middle of this century farmers had been benefiting from New Zealand's 31 million acres of pastureland without applying any fertiliser to the soil.

During 1948-49 the Government realised the urgent requirement for aerial fertilising to restore this soil to its correct chemical balance and the Royal New Zealand Air Force was made responsible for research, and extensive fertilising was undertaken with large aircraft, such as the DC-3. The work was charged for on a “county” basis and thus the cost was eased by the local rates.

I exhibited the “Silver Streak” before a patent was granted to me because my Patent Agent, the late Mr. Griffith Brewer, had asked me to allow him to make a search, and this took a considerable time. What he found as being the “state of the art” is described in my first patent, 185,992, in clauses 70 to 85 on the first page. (Application date, 10 November 1921; Complete Left 15 February 1922; Complete Accepted 21 September 1922). None of those projects described as being the “state of the art” were ever carried into practice successfully, and a study of statements in 70 to 85 will show that the Inventors had failed to realise that such structures as they visualised could not safely be made, as indeed they were never made, and carried into practice in an actual aeroplane or flying-boat.