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Input from Alan Matthews

THE REQUIREMENT

The requirement was laid down around 1965 for two Display and Data Handling vehicles to interface with the existing Type 13/14 mobile convoys and communications which we had earlier supplied to the SA Air Force.

Each system was to be housed in a Leyland Hippo vehicle, have 4 PPI displays with up to 40 rate aided tracks, alpha numeric track labels, intercept software, airfield status displays, and a communications system which would integrate with the existing ground to air and ground to ground equipments.

(Input from Cyril Froggatt: Two of the displays covered threat assessment and intercept control, one was for track production and tracking, plus a technical monitor console.)

IMPLEMENTATION TEAM

The system was to be implemented by a team comprising Bill Whale - Systems, with Bob Donaldson, Clive Gildersleeves, Alan Matthews - engineering design, and Brian Lewis, Doug Bromley and Brian Beardshall - software.  John Mumford was involved in Sales and Alec Stewart as Chief of Systems.

THE DESIGN

The equipment was housed in a large Leyland "Hippo" air conditioned truck and comprised  4 PPI displays with tracker balls and keyboards each with a tabular display mainly used for Airfield Status information which could be input at one of the positions.  At the rear of the cabin were two large equipment cabinets - one for the tabular system and the other for the analogue display printed circuit boards and the equipments associated with the necessary internal and external voice communications.

The equipment area also contained a 16 K Myriad computer and a Myriad peripheral cabinet which contained the necessary interface cards for printers, tape readers, VDUs, etc.  Radar turning information was input via selsyns with North auto alignment and this was housed in a small box above the computer.

DEVELOPMENT

The timescale was very tight and luckily the team involved did not mind working very long hours under great pressure - and in fact this enabled them to adopt many practices which did not perhaps conform with accepted methodology.

An example, was the problem of the supply of printed circuit boards, many of which the factory could not supply soon enough to meet the timescales.  Clive then organised the ordering of blank printed circuit boards and all the components for this large number of cards and when they arrived we set up a production line in the lab. The boards were assembled in the evenings by all the team - including the programmers and Bill Whale.  The completed boards were then put into the wired racks and tested as the equipment was commissioned. After this, factory inspectors came in and stamped the cards as checked and tested.

There was a problem of getting components after normal working hours and we had keys for the stores who found large quantities of component warrants in the morning - hopefully keeping the books straight.

During commissioning and testing some quite interesting ideas were tried - and I remember Bob Donaldson saying one night that it should be possible to display the positions of targets as extracted plots on the PPIs.  So I built a crude video clipper to deliver the radar video and some noise to the computer - while the ever brilliant Brian Lewis wrote some software which looked for radar strikes at about the same range and bearing and worked out the centre of the target.

This was all achieved with some success in a couple of hours and later formed the basis of a plot extractor for a later South African project and provided the test bed for the necessary parameters required for the Company plot extractor unit.

The system was finally ready for acceptance in the UK and the customer's representative informed.  The day before his arrival it was decided that the equipment should be subjected to some sort of "road" trials so that we could show that it was rugged enough to meet the shock and vibration criteria - though all the individual parts had been subjected to a very tough set of tests on the mechanical testers at Guy's Farm.

It had been noted that a large green area of a field in the Baddow Labs had some 6inch high concrete blocks on it which would be ideal to drive the vehicle over with Bill Whale inside to see how the equipment moved about.  So with Clive driving and myself as passenger we set off, but as we went onto the smooth green area, the vehicle sank in up to its axles - nobody had told us that the green area was the site of an old pond!  It could not be recovered by normal means and a large winch had to be hired to haul it out the next day - just before the Customer arrived to find a very muddy "New Vehicle".

In his presence we re-connected all the cables and it all ran up and worked straight away. The customer was very impressed with the thoroughness of our testing and signed up next day that the vehicle was fit for shipment for final acceptance in South Africa.

ON SITE COMMISSIONING

The team then built and commissioned the second MOV, while the first was being shipped, after which Clive, the three programmers and I went to South Africa to finish the commissioning there because as usual the software was not quite finished.  We took scopes and much other test equipment as baggage on the plane - carrying it by hand through the system with no formal paperwork at all - I dread to think what the excess baggage charges were.

The MOV worked well on site  - the worst mechanical problems being the Air Conditioning system and tape readers which all suffered from the fine red dust which blew into everything on the site.  When it came to checking the intercept software, after the radar receivers had been sorted out to give a reasonable range on a Canberra, it was found to be very difficult to complete an automated intercept using our software. However to maintain confidence in the system for the participating pilots, a South African Intercept Controller (Albe G) was used to complete the exercise "by eyeball" .  Brian Lewis then studied how this was achieved and successfully programmed "a bit of Albe's brain" into the software and the problem was solved.

After about three months commissioning on site Cyril Froggatt came out to do the acceptance trials with the Field Service engineer and I went home in November 1967 leaving Clive to complete the engineering tasks and run a  course for the Customer's maintenance staff.

CONCLUSION

This was a fantastic project, breaking much new ground, achieved in a very short time and I count myself very fortunate to have worked with such a brilliantly talented group of people even if most of them only performed at their best working "outside the box".

Related Link: Project Nassau

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