The CHAIRMAN, in introducing the Author, expressed pleasure in welcoming Mr NISBET who was a Founder Member of the Association and an Associate Fellow of The Royal Aeronautical Society

Mr Nisbet was educated at Glasgow Academy and the Royal Technical College, Glasgow He joined G & J Weir, at Cathcart, in 1936, as an apprentice and was engaged in the early development work on Autogiros and the first helicopters in this country He was for a short period Assistant Ground Engineer at Scottish Aviation, and for a further short period he was engaged as a junior draughtsman with Mr Hafner in the AR III Construction Company

In this part of the paper the theoretical considerations underlying the design of an autopilot system for helicopters are discussed, in particular, the system investigated has three modes of operation, viz —

1. (i) Stabiliser

   In this mode, whilst the pilot still exercises overall control, the autopilot introduces artificial stabilisation so that the helicopter becomes more easy to fly

2. (ii) Cruising

   Here the pilot establishes a desired attitude and heading in straight-line flight, on selection the autopilot maintains this mode of flight automatically

3. (iii) Automatic Hover

   Assuming that signals are available defining the plan-position of the helicopter with respect to the point on the ground over which the pilot wishes to hover, on selection the autopilot maintains this hover condition automatically

The Chairman, in introducing the Author, said that the occasion was a very auspicious one, in that a paper was being presented by one of the founder members of the Association at a Joint Meeting with the Royal Aeronautical Society, with which the Association maintained the closest of links On behalf of the Association he welcomed the fact that a joint meeting was being held, and he welcomed those members of the Society who were present to hear a paper and discussion on a specialised helicopter subject In particular he welcomed the President of the Royal Aeronautical Society, Mr E T Jones

Mr H FUCHS was born in Czechoslovakia in 1930 and emigrated to this country in 1939 He was educated at Northampton Grammar School, and obtained his Honours Degree in Physics at the Manchester University in 1952 Prior to obtaining his Ph D in Electronics, on the subject of helicopter computers in ground resonance, at Southampton University, he was employed in the Guided Weapons Laboratory at Vickers Armstrongs as an Electronic Engineer Since 1956 he has been with Blackburn and General Aircraft as Chief Electronic Engineer in charge of the Electronic Laboratory and the Electronic Design of Aircraft His work has included the design and production of Blackburn's analogue computer, and is currently engaged in designing an airborne analogue digital converter, fully transistorised, and associated electronic data handling equipment to a system of flight testing of aircraft

The Chairman, in introducing the Author, described the subject of his paper as one of paramount importance to all who were concerned in the design and operation of helicopters Mr Rogers was an indentured aeronautical engineer apprentice at the Fairey Aviation Company from 1940 to 1946, during which time he obtained the Ordinary and Higher National Certificates in Mechanical and Aeronautical Engineering He was awarded an S B A C scholarship to the College of Aeronautics in 1946 and obtained a diploma with distinction in Aircraft Design

The CHAIRMAN, in introducing the Author, said that although it had in the past been the main concern of the Association to discuss the problems of the conventional helicopter, it was now proposed to include systems allied to it, and convertiplanes and other powered lift systems would be considered at this and future meetings of the Association There was now a whole spectrum of proposed direct lift aircraft ranging from the conventional helicopter of a few pounds per sq ft disc loading, to jet lift aircraft of hundreds of pounds per sq ft of jet area Between these two extremes there was a variety of convertiplanes and jet wing systems

The Author had been working on rotorcraft for a long time He had been Chief Aerodynamicist of the Vertol Aircraft Corporation and Director of Aeronautical Research there, he had written many papers relating to the helicopter especially on aerodynamics, and his books on the subject published by the Rotorcraft Publishing Committee had been very widely read, even on this side of the Atlantic

In the first part of this paper the theoretical considerations underlying the design of an automatic control system for helicopters have been discussed This second part describes some flight experiments carried out at R A E , Farnborough In addition to demonstrating the validity of the theory presented, there has emerged from the flying a clear conception of the design features needed in a practical system for every day use by the average helicopter pilot

One of the more interesting aspects of the experimental programme has been in the fact that the results were achieved almost entirely from flight tests At the time when this work was commenced, aerodynamic information of the test aircraft was scanty Thus whilst the theoretical form of the control law was known, the optimum values of the control parameters could only be roughly forecasted and the actual values were obtained in flight

The design problem of a Helicopter Station in the Central London area was set to thirty students in their final year at the Department of Architecture, University College, London, in the Lent Term of the session 1955-56 The architectural problem posed by the provision of the very large area of landing space required under present operational conditions, with its attendant problems of the ground and air approaches and the use of the covered space provided by the flight platform, was one well worthy of study The design of such a massive building as this entails, to fit comfortably in the relatively small scale of present day London, poses a considerable architectural problem, to which as yet no entirely satisfactory solutions have been offered

The Chairman, in opening the meeting, said it was a matter of major importance to all concerned not only to have suitable helicopters to use, but also to ensure that when the operators got them they were capable of being used in such a way as to make nonsense of the frequently heard comment that there was no economic future in scheduled operations It was, of course, a fact that unless helicopters could be operated round the clock, in foul weather as well as fair, by night as well as day, like normal means of transport, then they would not take their rightful place in the general transportation set-up

The Chairman, in introducing the Author, said that Wing Commander Williams joined the Royal Air Force in 1936 and, after serving m Bomber Command at the beginning of the war he was unfortunate enough to be shot down in a Halifax bomber and taken prisoner After the war he spent some time on instructional duties, and in 1952 he attended the Royal Air Force Staff College In 1953 he was sent to Malaya to form and to command the Helicopter Wing, which also included a Naval Squadron He had, therefore, been very closely associated with helicopter operations for two and a half years Wing Commander Williams was now serving at the Air Ministry, in the Directorate of Air Transport Operations He is a Member of the Association

The CHAIRMAN, in introducing the Author, said that Mr VENNING had spent from 1941 to 1946 in the Royal Signals on mobile communications and from 1946 to 1949 at the City and Guilds Engineering College From 1949 to 1952 he had been in the Royal Naval Scientific Service, working on underwater acoustics From 1952 to 1955 Mr Venning had been at the College of Technology, University of Manchester, as a Lecturer in Electrical Engineering In 1955 he joined the University of Southampton in the Department of Electronics where, in addition to lecturing in electronics he was undertaking a research contract for the Ministry of Supply basically on the subject of his present paper