Development Inspection

Southend 1963-1970

By Chris Poole -- June 2005

I joined EKCO in May 1962 upon leaving school and I served a year working in the main production Auto-Machine Shop, where I learnt a lot about Automatic Lathes, Second Operation machines and measurement of components.

I also learnt very quickly the ins and outs of working the system to maximise the piece rate bonuses where each job had an agreed operation time. Work too slow and not only did you fail to earn a bonus, but you incurred the wrath of the foreman and the girls who had the job timed to perfection. Work too fast and you ran the risk of the job being re-timed by the time and motion man, with subsequent loss of future bonuses and wrath of the girls (again).

In May 1963, I heard that about a vacancy in the 'Electronics' Development Inspection, so after having a short interview with Roy Henstridge (who was to become my boss) I was accepted and so started 7½ years of total enjoyment working alongside Bill Boon, Bill Ray, Malcolm xxx, Alan Edwards and Ernie xxx. The foreman was Peter Thompson - a true Yorkshire man who thought that Yorkshire Cricket Club was the only club worthy of note. Later Jack Barlow, who was also one of Southend's best-known 'Master of Ceremony', joined us, which led to some lively debate about Cricket with Peter because he was a Lancashire man.

Bill Boon and Bill Ray had both at one time worked in the Maintenance Department and through them I heard many of the stories of the history of the company and some of the more famous antics of people over the years, some of which were quite racy!

When I joined the department, it was located in the old laboratory buildings dating from the late 1930's at the extreme left hand side of the site behind the R&D block 'running from front to back alongside the sports ground. The entrance to our area was opposite the internal car park behind the Engineering Tower block.

Over time I came to learn of the secret underground shelters and stores hidden below this car park and I once went down to the shelters with some of the maintenance men and I was amazed to find rooms still fully equipped with tables and benches. It was almost as if they had just been left as they were at the end of WW2. When I asked one of the maintenance men why there were tables etc, he told me that it was planned to be able to function and carry on limited production underground if needed during air raids?

Later on, we moved to bigger accommodation at the rear of the original R&D building where we were adjacent to 'Gibbys' Mechanical Lab, which made a lot of sense due to the mechanical nature of our work.

The role of the Development Inspection Department was primarily a mechanical inspection of everything made in the 'Model Shop' as well as checking bought in goods, which included electrical components although Ernie's role was checking the prototype wiring looms.

The inspection department, in those days did not have any of the modern aids considered essential today such as CMM's since these were not yet invented and all measurement was manual using traditional measuring instruments and a lot of maths was needed to do all the calculations needed.

Since a lot of the parts we were inspecting were development items, when we found faults - sometimes in the drawings themselves, we were expected to liase with the drawing office and/or the project team rather than just reject the parts.

By this means I was able to have what was perhaps a unique insight to the workings of many of the labs and the people working in them.

In rough chronological order, the following are some of the development projects we handled.

E190 gearbox and scanner unit.

This was still coming through although it was in the pre-production stage but nevertheless there were still proving trials going on. To me this was a remarkable piece of engineering and so lightweight. I believe that one big target was that the gearbox should weight less than 7 Lb Gibby had calculated all the relative weights of the components purely using his monster cylindrical slide rule and I believe that when it was actually weighed it was bang on target weight.

A company called SH Muffett manufactured the Spur Gears inside the gearbox in Aluminium and this was one of the first challenges I had to overcome since I had to learn how to check spur gearing and we had none of the electronic devices available today.

The gearbox casting was a magnesium alloy, which was vacuum impregnated with Aeridite this giving it great strength with ultra lightweight.

The E190 scanner unit as a whole was ascetically pleasing to look at and a testament to Gibbys design principles and although I believe that there were concerns that the engineering would be man enough for the job, time has justified his design since there are E190 systems still flying daily some 40 years after build.

Helicopter radar ARI 5955

This project was just starting to have parts made and was a radical change from any other system previously made both in gearbox and scanner design as well as the indicator unit.

Unusually for EKCO, the mechanical design was not by 'Gibby' but by a consultant engineer called 'Dennis Thorpe' who brought into the project to give a fresh approach and the design he evolved certainly was radical.

My first involvement was when we received the wooden pattern moulds for the new gearbox, which would be used to make to sand castings. These had to be checked to make sure that they were of the right shape and size to produce the castings, which was a bit tricky since we had to make an allowance for the shrinkage etc.

Once we saw the first casting made from the mould, this then had to be thoroughly checked both for size and to make sure that there was an adequate machining allowance to allow those faces, which needed machining. This involved painting all the surfaces to be machined with a blue marking out ink then scribing with a height gauge nib all the finished sizes. This was a laborious process, which had to be done in all 3 dimensions and took about a week to complete but at when finished gave a visual representation of the finished casting. Today using a CMM this check could probably be done in a day.

I can't remember if the prototype castings were machined in the 'model shop' (I think they were) but we again had to spend another week checking the finished item.

While the gearbox casting was being machined, the spur gears started to arrive for inspection and to me it was a marvel then and still is now how all this gearing could fit inside the casting.

Unlike the conventional gearboxes where the top of the gearbox was detachable to allow assembly, with the flat design of the helicopter gearbox, assembly of the gears had to be through the holes in the casting, which at a latter date would be for the servo motors.

Needless to say, this was a challenge and required a lot of skill and patience to get the build up right. It is a testament to the skills of the instrument mechanics such as my father that this unique gearbox design was made to a standard, which was later able to go into production without too many radical alterations.

Helicopter Scanner

The next big item we checked was the scanner dish, which we had to check as a whole. This dish was a parabolic dish about 3 feet in diameter. A metal spinning technique was used by a specialist firm to form these dishes and this dish was, I believe the largest dish used by EKCO although the same size dish was an option on the later E390 Concorde radar.

Checking parabolic scanner dishes was another long laborious process, which was entirely a manual inspection using a special test rig, which was made for the purpose. In simple terms the dish was held in a jig as shown below.

Dish Checking

The horizontal plate touching the dish was supported so that no weight was imposed on the dish (thus giving distortion) and the diameter of the plate was approximately the same as the focal point. In the plate was a series of holes drilled at ½ inch centres.

The depth gauge was used to take measurements every ½ inch from the inside to the outside of the dish and this was repeated at 120 degree intervals (i.e. Each dish was measured at 3 points around its circumference), which on a big dish such as used on the helicopter radar meant an awful lot of manual work and some 180 readings.

Analysis of the readings confirmed the parabolic shape of the dish.

These dishes were notoriously malformed in their early days with the result that the reject rate was very high, however as experience was gained spinning these large dishes the problems of form were overcome.

Once we had passed the dishes, they had stiffening formers riveted onto the back and only then were they cut into the final shape required. This was a 'one time' exercise since once it was cut it either was OK or not.

In the development team, this was done either by my father 'Dennis Poole' or his assistant 'Bill Jones'

Attaching the dish to the gearbox was a fabricated assembly, which was commonly referred to as the 'Bull Horns' for obvious reasons (see photo) since they did resemble Bull's horns.

Due to the flat nature of the gearbox and the need for the dish to rotate 360 degree's in the centre of the gearbox was a central tube, which not only was the central support for all the gearing but also carried the wave-guide through from top to bottom.

This central tube was turned from solid Aluminium and had to be made to extremely tight tolerances with virtually every dimension being critical, needless to say this involved a lot of skill to manufacture and due to the plating, which had to be applied, a lot of these were scrapped due to distortion. As before these problems were eventually overcome but this one component probably remained the Achilles heel of the mechanical system.

The next major components we saw were the castings, which fitted underneath the indicator console. These castings supported the small 2-½ inch CRT and supporting focus coils. These were also complex shapes and required a lot of precision machining.

Helicopter Display Unit

Another big job was the manufacture of the indicator unit, which the mechanical lads commonly referred to as either the 'Coal Scuttle' or the 'fish fryer' although the senior engineers probably frowned upon this description.

What was unique about this unit was the fact that the whole assembly was fabricated using the 'German Toy' technique, which to the uninitiated is a method whereby one part is made with rectangular slots and the mating part has projecting tangs. These were big pieces of Aluminium and had to be checked very carefully due to the need for all the slots and tangs to line up. When the two parts are assembled, the tangs engaged through the slots and given a twist to lock them in place. A special paste was used, as a jointing compound, and the whole assembly 'dip brazed' in a salt solution at quite a high temperature, thus effectively welding the whole structure. A specialist company called 'Delaney Galley' did the 'Dip Brazing'

Some firsts

In the front of the unit, there was a 24-inch 'Fresnal Lens', which was held in place by being sandwiched between two castings. In the lover casting bolted to the casing, there was probably the first use in the UK of 'Screw Lock Thread Inserts', which caused many problems in the early days due to difficulties in having the right tooling, which caused the thread behind the locking element to jump a thread. The net result of this was that I spent many hours testing each thread in the housing and that meant checking a lot of threads.

Another first was the evaluation of 'Velcro', which was the 'wonder' new fixing looking for an application. One use it was considered for was the method of holding the internal mirror in place although it ended up never being used.

Later on an evaluation was made of 'Loctite' as a means of 'thread locking' although this was not adopted due to MoD concerns about this medium as a means of providing 'anti-vibration' thread locking.

E390 system

The E390 was the last major system developed at EKCO. This unit broke yet more new ground since it was developed to meet the stringent parameters required for Concorde although the system was also developed for the Jumbo's, which were due to enter service in the late 1960's.

As developed for Concorde, the system had to have -- for the first time -- a high level of built in redundancy. This resulted in there being, wherever possible a dual operating system known as port and starboard. To ensure that parts were fitted correctly, they were painted or plated red and green to indicate Port and Starboard!

Due to the high speed of Concorde, there also had to be the facility to double the range i.e. a 360-mile detection range, which was achieved by having a very narrow 'pencil beam' function.

Concorde Scanner

One of the big concerns in the design of the scanner unit was the anticipated temperature the unit would have to operate at in flight. I recall that there were different numbers being spoken about, but there was a general feeling that the operational parameters would be a problem for normal soldered joints using conventional solder.

As a result of this, 'high temperature' solder had to be developed, which of course also meant that high temperature soldering irons were developed. A spin-off from this was that the joints themselves also had to closely looked at so that there was no detrimental effect of heat soak when soldering.

One other problem was with the Wave-guide horn pressure cap. If I recall correctly, the 'golf ball type cap' was made in what was then a new material called 'Phenol', which had to be made in three pieces and then glued together. This I know posed some major development problems in getting a glue to work and I think this was compounded by the system being pressurised to a higher value to take account of the higher altitude Concorde would fly at??

Apart from this I cannot recall any other scanner issues??

The other unit, which I know gave mechanical trouble to the development team was the Cockpit Control Unit in that the push buttons were all mechanically operated through a latching system where the buttons pushed down what can be best described as a 'spike' in a tube, which had a channel at the bottom containing ball bearings.

The theory being that the spike displaced a ball bearing thus another button could not be pressed until the original button was released.

Getting this to work properly took some time and a lot of experimentation.

Concorde Control Unit

The E90 system

The E90 system was the smallest weather radar of the EKCO family and was developed in the mid 60's to meet the needs of the new generation of 'light twins' such as the Piper Aztec, the Beech Queen Air and the Beagle 206 for example, which were becoming popular in private ownership towards the end of the 1960's.

When I first say the lab model, I have to say that it appeared rather crude and almost toy like compared to all the other sets.

E90 Scanner Unit

What I do remember was checking the scanner dish; this was so small (about 12 inches diameter) that it would not fit onto the dish checking jig and special adaptors had to be fabricated.

While I don't know if the system was ever commercially successful, it certainly showed that EKCO were keeping an eye on how commercial and private aviation was developing.

Miscellaneous Memories

In working in Development inspection, we got to see and be involved with a lot of projects, some of which never came to fruition as well as some extra curricular activities.

One of the most frightening duties I had was using the 'Magnetiser' which was a device designed by John Yarrow and used for imparting a high magnetic field into the soft iron blocks moulded into various components.

It was frightening insofar as this piece of equipment was in its own room adjacent to 'Gibbys lab' and I had strict instructions to remove any metallic objects, including my watch before entering the room and switching on.

I swear when the 'Magnetiser' was switched on the lights dimmed and it emitted an ominous hum akin to the sort of noise heard in the Frankenstein movies. I don't know what the power consumption was but by the size of the power leads it must have been considerable. Suffice to say that using the machine was not popular and I did sometimes wonder about the highly magnetic environment.

The Wave-guide Lab.

In my travels, I used to visit Pat Heath's lab and remember this was a place where there was always a convivial atmosphere and I have two abiding memories. The first is Bob Puttock's calculation for working out the changes in wave-guide propagation through the droop snoot of Concorde. This was I know considered a 'tour-de-force' at the time since all the calculation was done long hand with only a slide rule for help and for a long time I remembered it stayed on their large back-board.

The second abiding memory is the seemingly casual way they used to heat up pies and sausage rolls etc by pointing a wave-guide horn at the food -- this some 20 years before microwave ovens became popular.

The Environmental Test Lab.

This was a new building built behind the engineering block in the mid 60's.

What was fascinating about this lab was the fact that it was equipped with 2 large vibration tables (made by Ling I think?) upon which a scanner unit or a T/R unit could be mounted and vibrated over a wide vibration range going down I think to 20Hz.

The object of this testing was to simulate the vibration regime of the aircraft or helicopter.

I recall that one of the party tricks to demonstrate the equipment to important visitors was to take a TV from the main production line and watch it self-destruct in a very short time.

In the second part of the building was an environmental chamber where equipment could be subjected to 'tropical' conditions.

One of the big concerns about the building being where it was the fact that the vibrations would transmit through the foundations or the roof and affect the adjacent engineering tower block and cracks certainly did appear in this building with plaster and brick dust known to fall onto drawing boards in the D/O on the top floor.

The scrap chit.

With security staff on the front and rear entrances (they never apparently twigged that you could leave through the gate from the sports field) to take anything off the site you had to have a chit.

Of course this was only used for objects, which would not fit into pockets (valves and small components such as resistors etc. were considered fair game and worth the risk of getting stopped for a random check.) but up the early/mid 60's the top of the range TV cases were still made of mahogany or if it was a Dynatron even teak.

The net result of this was many of the staff sought out scrap TV cases from the 'Willow Run', which were taken home and used to make coffee tables for example.

The procedure was that you should take the piece of wood you wanted to the 'Scrap Officer' who worked upstairs above Personnel and he would evaluate the piece and issue a scrap chit upon payment of a small sum such as sixpence (6d) or one Shilling in old money and it was not unknown for the teak pieces to be up to 5 shillings if it was from a large 24 or 26 inch cabinet.

Of course everybody soon wised up to this with the result that many departments had a suitably badly scratched piece of wooden cabinet, which was taken to the Scrap Officer whenever you found a good piece of wood.

We used to have bets on how much he would charge and never ceased to be amazed by the variation in price for the same piece of scrap wood.

George (Gibby) Gibson.

'Gibby' as he was known to everybody was the Chief Mechanical Engineer and dare I say it a Brilliant Designer if somewhat eccentric, but even though I was a young whippersnapper at the time and thought everybody over 30 was an old fogy, he was a person who I came to have a very high regard for.

Stories of Gibby are legend within the circle of engineers who worked with him over the years and he was just as famous for his 'unorthodox' dress style, which even today in the more relaxed working environment would still be considered 'bohemian'.

Many was the time when Gibby could be seen striding down the corridor where the directors resided wearing a baggy old pair of corduroy trousers, which looked and probably were the same pair he'd been gardening in judging by the mud on them wearing a 'Fred Perry' Tennis shirt and a tie with the shirt and the tie having soup stains on them and did he care -- well NO seemingly.

One of the great joys was going to see him with a query and asking him if the component in question (with an out of tolerance dimension for example) could still be used or if it needed re-making??

As often as not, Gibby would say 'well let me think about this' and he would produce from his pocket a rather grubby handkerchief, which he would proceed to chew upon and almost look like he was going into a trance!!!

What he was actually doing was mentally working through all the mating parts, which could be affected and doing sums in his head of how this 'out of tolerance' part would affect the overall assembly.

This process sometimes seemed to go on for ages and only rarely did he have to give in and resort to using his giant cylindrical slide rule. Incidentally I can't remember him ever being wrong.

Gibby was a proud Scotsman and always insisted that the Scots have only loaned England to us, he was also immensely proud of AVIS, where he was apprenticed and waxed lyrical of his time there and the great cars they built.

I think it's a testament to his design skills that the E190 system is still flying in service use over 40 years after he designed it.

More later !!

Chris Poole

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