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Newsletter 24
Summer 2009
Updated on 20May2009
Published by the Hawker Association
for the Members.
Contents Hawker Association

Contents
Editorial
AGM
Cygnet News
F-35B Lightning II News
Folland Spirit Of Hamble
Harrier News
Hawk News
Hawkers In The 1950s
Hawkers in The Late 1930s
Hurricane News
Members
Programme
R&D Department
Tempest News
Testing V/STOL Projects
World War 2 Experiences
 
   Norman Long recalls his time in the Research and Development Department...
    I joined Hawker Aircraft at Kingston in 1962 as a sixteen year old Engineering Apprentice. One highlight of my first year in the Apprentice Training School was a talk on structural testing by Derek Thomas from Rochefort's then R&D department. This was followed by an exciting tour round the huge airframe test frame and the labs. in the Experimental building. I remember being introduced to Derek's 'boys' - probably Richard Cannon, Colin Flint, Brian Indge and others - in the main control room and being fascinated by all the sophisticated electronic control equipment and the rigs they had developed.
    I had an interest in making radios and other electronic devices and after seeing what they did, their enthusiasm, the stimulating work, and the general camaraderie of the team, I was determined that this was where I wanted to work when I finished my apprenticeship.

 
The R&D Department In The Sixties And Seventies

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    In the years that followed I made frequent visits to the lab., usually on the scrounge for the odd transistor or other electronic component from the scrap box to use in my own projects at home. As a result I got to know Richard Cannon and the other boys in the lab. really well.
    Derek Thomas, later Head of Ground Test Services, was one of the most charismatic engineering group managers I have ever known. He had a way with words which would make his engineers feel ten feet tall, invincible and prepared to take on anything! Once when I was in the lab. during one of his weekly tours he said to me, "Oh, you'll have them eating their own young next", likening the electronic equipment I was developing to an animal creation. Such interest and encouragement was really motivating for the young engineer. Derek had a good awareness of the skills and attributes of the people in his group and was always finding new ways of raising the bar and challenging the team. As a result he was adept at selling ideas to the directors and other senior management to fund new and exciting projects and equipment which encouraged success in the group.
    One of Derek's 'hot buttons' circa 1966 was an idea to replace the g meter fitted to aircraft to assess structural fatigue. The g meter counted the g excursions encountered during flight and Derek wanted to substitute a meter that counted load excursions measured by strain gauges mounted at key points of the structure. He believed that this would give a far more realistic picture of actual airframe fatigue. Subsequently when I passed through R&D on my apprenticeship tour of departments I got the job, under Richard Cannon's magical mentoring, of doing a design study to investigate the feasibility of this idea. The study started with the writing of a computer programme, for the early Ferranti Pegasus valve computer using the Autocode programming language, to simulate a fatigue counter with, say, twenty or more key load points each with ten or more load excursion counters. Periodically the load excursion spectrum of counts for each point would be dumped and subsequently analysed for cumulative fatigue damage. The study then went on to investigate the viability of producing a prototype based on the Ferranti FM1600 airborne computer that fitted in a standard ATR airborne equipment box.
    Once the study was complete I went with Derek and Richard to the RAE Structures Department at Farnborough to discuss the idea with them. While we were there we were invited to go down to the structures lab. to see the Concorde fatigue test which was controlled by a Digital Equipment PDP10 computer. The whole thing was quite something, particularly the way the airframe skin temperature had to be heat cycled, to simulate supersonic flight, in addition to the normal load cycling with which we were familiar.
    During the last six months of my apprenticeship and when it was completed I finally joined Richard Cannon's Control Engineering section working initially on signal conditioning and electronic control equipment for the Kestrel static strength test. It was now circa 1969 and there was some concern over the fatigue life of the Folland Gnats used for training at RAF Valley and by the Red Arrows. Given Derek's earlier load excursion fatigue counter interest I assume he used his influence to utilise this Gnat problem as a means of initiating a project to develop a prototype fatigue counter or meter. The scheme consisted of instrumenting with strain gauges the tailplane or fin of one Red Arrow Gnat and one from Training Command . An electronic unit then evaluated any changes in load relative to four pre-set levels and recorded them on eight numeric counters, four up and four down. I did the electronic and printed circuit board design and Alan Abbot, originally from the lofting department, did the mechanical packaging design and the changes necessary to fit it all into the aircraft. The main unit with counter display was fitted in the cockpit and a small strain gauge preamplifier was fitinatalled in the fin through a small access panel.
    For convenience the equipment was fitted first to one of the Red Arrows which at the time was on summer detachment at RAF Kemble. Over the summer we went to Kemble a number of times but could not get access to the aircraft until after flying had finished for the day. Therefore during these airfield visits the drill was that Alan would pick me up at about 11.30 am and we would drive to Kemble, stopping off at the Star Inn in Kingsclere for a nice carvery lunch. Then on to Kemble arriving at the airfield at about 3.00 pm to start work in the hangar as soon as the aircraft was available, working until late evening. Unfortunately, during the initial commissioning trials we had lots of problems with spurious counts. After discussion with the RAF it was decided, that to start with, a pilot would taxy the aircraft round the airfield and along the runway with Alan in the back seat observing any problems. Subsequently we discovered that when the pilot transmitted on UHF, radio frequency interference was induced in the signal cable linking the preamplifier in the fin, from the adjacent UHF aerial feeder in the spine. Given the power this was a difficult problem to solve but after involving virtually all the electronic knowledge in the Control Engineering Section. the preamplifier and screening was hardened sufficiently for the system to work satisfactorily in this harsh EMC environment.
    Later the 'Reds' moved down the road to RAF Fairford where Concorde was on flight trials. During our visits we felt privileged in being able to observe some of the Concorde work. One day a very bad thunderstorm broke out while we were working in the hangar and even with all the noise of the torrential rain on the roof we could still hear the Concorde at the end of the runway. Everybody, including ourselves and all the RAF 'erks', rushed to the doors to see what all the commotion was about, only to get nearly drowned in the water gushing off the roof. There she was, in all her power and beauty straining on her brakes with full reheat, then accelerating flat out down the runway for a maximum braking test just before taking off. Of course we realised that the Concorde flight test engineers were using the opportunity to complete some wet runway braking test; but what a sight! 
    The prototype fatigue counter was subsequently also fitted to the training Gnat and produced some interesting results. Contrary to what one might think, it was observed that the generally higher g flight profile of the Red Arrows was often causing far less fatigue damage than that of training flights. As a result of the fatigue programme, the extrapolated remaining fatigue life, particularly of the training aircraft, was reduced significantly resulting in the Gnat being retired earlier than planned. This put more pressure on getting the Hawks, which would replace them, into service.
    The project was a tribute to Derek Thomas who had always been there as the visionary behind real-time airborne fatigue load monitoring. In modern times with fly-by-wire and computerised stress analysis and simulation there is more known data and the problems are better understood. It was with great shock and sadness that I learnt of Derek's premature death in the 1980s after I had left Hawkers to join Digital Equipment Corporation in 1977.