"David Thomas's Cottage Industry" - Leicester and CMM


Introduction

A contribution from Alan J Davies on the New Parks site at Leicester, including CMM et al.

 

Early Data Handling

This year, 2019, is the fiftieth anniversary of "David Thomas's Cottage Industry".
In 1969, in what was then the Marconi Radar Systems division at New Parks, Leicester, a small group of engineers was set up under the leadership of senior engineer David Thomas, with the title "Data Handling and Display", DH&D. It was to provide support systems for the main radar business on the site, including producing training simulators, as well as control and monitoring equipment. One of its first enterprises was the installation of the monitoring suite for the 909 radar on the type 82 destroyer HMS Bristol. The system consisted of about ninety built-in test points within the radar, all hard-wired back to the Master Monitoring Unit, or MMU, a cabinet-sized bank of filament-lamp alarms (the lamps were glued-in so as to withstand the ship's vibration, which meant replacing a blown bulb was, quite literally, a shattering experience).

 

Instrumented Runway Visual Range

When I joined the unit, in 1971, it had begun looking at at airfield instrumentation, and was in the process of installing Instrumented Runway Visual Range (IRVR) equipment at the major UK airports, including Heathrow, Gatwick and Manchester. The easily-recognisable pairs of yellow fibreglass "Daleks", as they were nicknamed, housed, respectively, light sources and reflectors. By measuring the proportion of light scattered between them, visual range could be calculated and presented to the control tower within seconds, thus allowing for the runways to be safely kept open for the different categories of aircraft for as long as possible. The group was also investigating Slant Visual Range (for the aircraft's approach). According to the physics, the scattering properties of spheres (as in fog water droplets) is governed by the total scattering area, and not by the individual spherical radii. Thus it was that one of my first jobs in the department was to stand atop a stepladder in the field outside the building holding a lavatory ballcock on a stick while someone fired a megawatt lamp at me in order to calibrate the equipment.
Because the visual range needs to be calculated – and using different algorithms depending on the ambient light levels – the system used a computer: a DEC PDP-8, one of the first mini-computers to be used in this country. This unit boasted an impressive 4 KB (yes, that's kilobytes!) of RAM, and was programmed in machine code.

 

ScATCC - CMM

When Marconi Radar was awarded the contract to install the new Scottish Air Traffic Control Centre at Prestwick in 1973, the Leicester unit was given the task of remotely controlling the Air Traffic Control Radars themselves (situated on various Scottish mountain tops and islands). It was decided to implement these on-site installations using general-purpose computers – in this case DEC PDP-11s, based on the experience of using the PDP-8s for the IRVR systems. Modules implanted in the radar equipment measured, digitised and transmitted signals back to the PDPs, which then communicated via serial links to the main control centre at ScATCC.
Using the PDP meant that monitoring systems could thereafter be offered independently of the systems which they were monitoring, which, in the case of GEC radars and systems, might incorporate Locus-16s, GEC-4000s or even Ferranti FM1600s. The system was therefore christened "Computerised Modular Monitoring", or CMM. Ultimately all the ATC radars in England and Scotland were equipped with CMM (the English ones reporting back to LATCC in London).
The PDPs were programmed in CORAL66 – a NATS and MOD requirement. There were, however, at the time, no suitable realtime operating systems for the PDP-11, so we wrote our own – named, somewhat unimaginatively, "COPS": Computer OPerating System.

 

Civil Systems

By now the group had been renamed "Civil Systems", with a remit to find applications for the company's technologies in non-military (albeit still high-spec) civil applications, including the CAA, Ministry of Transport or the emergency services. It began to diverge from the major naval and radar businesses of the site, and was often referred to colloquially as "David Thomas's Cottage Industry". It continued, however, to do steady business. CMM was, in fact, to find a new application in the instrumentation of road tunnels. Since the detection of poor visibility in road tunnels is critical, as is the operation of the lighting, ventilation, groundwater pumps, traffic signals and so on, this brought together two of the group's main strands of expertise. A number of tunnels on the M25, the A1M and the A55 eventually all had CMM installations. The group also engaged in consultancy work for a number of European tunnel projects.
Civil Systems was closely associated with a number of projects in the Simulation and Training department at New Parks, with some engineers having a foot in both camps. The cutting-edge TEPIGEN visual simulator (which, again, used PDP-11 computers for its scenario processors) found application in bridge simulators for ships, and, at one time, was a front-runner for RAF aircraft simulators, before the seemingly inevitable MOD budget cuts.

 

Fire Brigade Applications

The last major step in the group's progression occurred when, in 1987, the development of a new London Fire Brigade Mobilising System, initially begun at Trafford Park, was moved down to Leicester, and into the Civil Systems group, together with a number of its engineers. The system was based on dual GEC4000 series computers (and eventually saw service for over ten years with an impressively high availability record).
Under its original remit, Civil Systems then sought to expand the business into other fire brigades.
At about that time, the Home Office produced a requirement for all brigades in England and Wales to report a series of Output Measures and Performance Indicators – OMPIS – to record and evaluate their activities. Up till then, each brigade had recorded a variety of different subsets of information, based on their own criteria, and usually on paper. Many found it difficult at relatively short notice to meet the government's demands. In partnership with the local - Leicestershire – fire brigade, Civil Systems installed a system which – much like the earlier CMM – took the approach of using a separate computer – in this case a Sun Microsystem – to remotely interrogate and record data from the brigade's existing mobilising equipment. This Management Information System, or MIS, enabled the brigade to report all 31 of the new OMPIS in the first year. In 1992, Durham Fire Brigade announced a complete replacement of their Control Centre. This provided the opportunity for Civil Systems to bid a mobilising system based on the London one, plus an MIS based on the Leicestershire prototype. Awarded the entire contract, the group installed equipment in the control centre and all of the fire stations, together with all the wiring, tele-switching, control consoles, displays etc in the new building. The system was formally opened in 1992 by the local MP, one Anthony Blair (whatever happened to him?).
Systems were subsequently installed in a number of other brigades, including those where the MIS was installed in conjunction with other, existing mobilising systems. Brigades as large as Strathclyde, Lancashire and Greater Manchester were amongst about a dozen brigades using one or both of the Marconi systems by the end of the 1990s.

 

Endgame

In 2000, following the transfer of the Leicester site to BAEsystems, the Civil Systems group was deemed to have diverged too far from the core business on the site (and of the company as a whole, following the split of the defence sector of Marconi from the rest of GEC). Consequently the group, consisting at the time of just over 30 staff, was sold off, together with the its business and client list, to the Petards group. The group – now known as Petards Civil Systems - moved to new premises in the nearby Meridian Business Park, and then on to Enderby, a few miles away. By now the group had branched into supplying in-cab systems, and new Fire and Ambulance despatch systems, as well as upgrading its MIS systems to a next-generation Incident Recording System (IRS) which communicated directly and interactively with the Home Office's Fire Control System.
In 2004, a management buyout saw many of the staff - including myself - taking the opportunity to own a part of their company. I left, taking early retirement, in 2008, after 37 years with the group. The final chapter of GEC-Marconi in Leicester came with the closure of the New Parks site in 2011. Walking the empty corridors prior to demolition was a particularly poignant moment.
As for Civil Systems – “David Thomas's Cottage Industry”? Well, now named 3TC Software (after the directors' initials) it is alive and well and thriving in new premises in Desford, less than 4 miles from where it began