For decades, the Underground largely designed and specified its own trains which were assembled by Metro-Cammell – now the Washwood Heath plant of Alstom Transport. But in 1984, the economic downturn saw a freeze on Underground orders and Metro-Cammell nearly went under.
Not until 1989 did LU order again and by then the world had changed – both LU and British Rail were into procurement by competitive tender against performance specifications. Actually, both organisations' engineers still went into extravagant detail but, in theory, it was procurement by competitive tender.
Having been married to Met-Camm for decades, it was understandable that LU's engineers fancied a new trophy wife. And the recently privatised British Rail Engineering Ltd (BREL) was every old roues' dream – young, inexperienced (bidding for its first Tube train), eager to please and innocent when it came to real costs.
And so, in September 1989, BREL won the contract to build the new Tube stock for the Central Line. And ran into the predictable problems on costs, delivery and reliability.
Before BREL's travails, I can remember an LU engineer telling me that Met-Camm, by now GEC-Alsthom, was out of the Tube train business for ever. Having lost the Central Line fleet, the Birmingham plant would fall behind the state of the technical art and cease to be a credible competitor.
Not for the first time Met-Camm's fiery Managing Director Bryan Ronan had been discounted. Thus, in 1992, when LU went to the market for the Jubilee Line Extension Stock GEC Alsthom beat off bids from BREL, Kawasaki of Japan and Bombardier/Siemens to win the order.
For BREL, shortly to become ABB Transportation, this was a major blow. The 1064 day main line train order hiatus was beginning to bite and a follow on order was essential to keep the production facility built for Central Line occupied.
In 1990, before the economic downturn, LU's Northern Line Modernisation project team had been looking to start replacing the oldest train fleet on the Underground in early 1995. Here was ABB's follow-on order. The Treasury was warming towards Private Finance Initiatives (PFI) so if ABB supplied the trains under an operating lease, the deal would be outside the Treasury's Public Sector Borrowing Requirement – provided the manufacturer took on enough risk.
ABB submitted its speculative Northern Line proposal in October 1993. It offered a fleet of just over 600 vehicles costing £440million, plus a 20 year maintenance contract worth another £300million. The pioneering concept went down so well that at the end of March 1994 the Transport Secretary gave LU the go ahead to invite tenders for a Northern Line train fleet under the PFI.
ABB was stunned. Its brilliant idea was going out to tender. Interestingly, the LU bidding was being run by a personable young turk called Richard Bowker.
Bids from GEC Alsthom, ABB and Bombardier went in on 1 September 1994 and Washwood Heath, under Ronan's leadership, was ahead of the game again. He realised that where the PFI would make money was not on the trains but on the whole life train service provision contract.
Playing it long was the key to success, accepting short term pain for long term gain. GEC Alsthom's initial bid blew away Bombardier in just four weeks and left ABB struggling.
Not just on price, either. GEC Alsthom was also ahead on traction drive technology. The Central Line had Brush GTO chopper, GEC Alsthom's parallel Jubilee Line trains would be GTO three phase drive, but Northern line would gamble on the next generation Onix IGBT three phase drive supplied from a reorganised Preston plant.
In December 1994 GEC Alsthom was declared the winner on all three criteria: quality, including delivery, number of trains and technical performance; price in terms of the payments over the 20 years; and risk transfer.
LU quoted a notional value for the trains of £400m plus in 1994 money; I estimated that it was nearer £370million. But the money that really mattered was the £40-45million a year, 20-year, total train service provision contract that the trains initiated, with a potential extension to 36 years.
At the time LU claimed that the bidding was close. Bowker now admits that the deal would have been unaffordable at ABB's prices.
To manage the PFI, GEC Alsthom set up a new company Northern Line Service Provision. This was an early Special Purpose Vehicle which funded the deal. It bought the new trains, funded the £30million investment in the depots, is paying for the maintenance and also pays for the supporting contract with Marconi for the key radio communications network.
GEC Alsthom's contract covered 106 six car trains to meet 96 diagrams, with the first units due to enter service in mid 1996. Meanwhile the service provision company would take over the LU depots at Golders Green and Mordern, with 180 staff and modernise them to handle the new stock. This included responsibility for maintaining the existing Northern Line 1959 and 1972 Tube Stock as a service provision deal.
While GEC Alsthom moved fast on taking over the depots and transferring the LU staff, the new trains were a long time a coming. The first London saw of the new 95 Tube Stock, was on a float in the Lord Mayors show in November 1996.
When the first train arrived the following month it was already a year late, although it was expected that deliveries would catch up over the long production run. Part of the reason for the delay was that the Northern Line trains were not JLE clones.
Bogies, traction package and bodyshells were all different, reducing commonality between the two builds to around 40%. But the short term pain was worth the long term gain, with bogies and traction packages both major contributors to the trains' success.
At the end of 1996 LU was expecting to infiltrate the first train into service at the end of August 1998, with the last of the 106 entering service in January 1999. In September 1997 the first train received it's qualified acceptance certificate (QTOC) and the Service Provision Contract for the 95 Tube Stock began.
Infiltration into service started in June 1998, but the last train was not completed at Washwood Heath until May 1999, when 43 trains were in service out of the 83 delivered and commissioned. It was not until Christmas 1999 that the existing fleet ran its last service.
To find out what happened next, I visited Golders Green in December 2001. GEC Alsthom was now Alstom and the company's train maintenance and service operations which includes the former BRML works at Eastleigh , Springburn and Wolverton plus the LU and Virgin West Coast train service provision contracts, had become Alstom Transport Service UK . Within this subsidiary, responsibilities are further divided into Traincare (main line) and Metrocare, the Northern and Jubilee Line operations. The Jubilee Line fleet has a similar train service provision contract, but the trains are owned by LU.
It was a timely visit because Golders Green had its tail up. A week before, during celebrations marking the 75 th anniversary of the Northern Line's southern extension, London underground had declared the Northern as the Tube's top performing line and Transport Minister John Spellar had said that the line's success was the best example of what could be achieved through a partnership between the public and private sectors.
Given the generally negative reaction to the Underground's PPP, you might expect LU and Government to boost any success. But, as Metrocare Operations Director Ian Clayton revealed hard figures back these claims.
Train service provision contracts are unforgiving and the reality is that new trains are prone to unreliability. You can test all you like, which is not possible on a busy Underground line anyway, but the first exposure to real passengers, the vagaries of weather and infrastructure and self-inflicted wounds as staff get used to driving and maintaining equipment under the pressures of meeting daily service demands, mean that shiny new trains have more problems than the stock they are replacing.
A mature customer accepts this and looks for reliability growth linked to contractual milestones. Achieving or beating these milestones is usually linked to bonus payments and vice versa.
Under Metrocare's contract with LU, reliability is measured as the mean distance between failures (MDBF) in kilometres. A service affecting failure is one that delays a train 2 minutes or more.
Measures such as MDBF represent shades of grey rather than black and white, worse and better rather than good and bad. For depot engineers they are a way of keeping the score while giving train operators the basis for financial incentive regimes.
Thus, in 1995, when Metrocare took over service provision using the 59 Tube Stock , the existing trains were giving around an MDBF of around 2000km, or five failures per 10,000km. Under the Service Provision Contract, the target was set at 3.3/10,000km and Fig 1 shows the results.
But with the 95 Tube Stock commissioned ,the real pain began. Figure 2 shows Northern line reliability growth from January 1999 when the full fleet became available.
With an MDBF around 2000km, performance was similar to that of the ‘Silver Slugs' when Metrocare took over the Depot. In fact, during infiltration it had been even worse.
Throughout 1999 it was the usual case for new equipment with maximum effort from the Depot Teams, apparently gaining little reward. In Figure 2 the blue line is the four weekly MDBF figure while the red line smoothes performance over 12 weeks. As an engineer, the blue line provides moments of cheer, the red line tells your boss you are actually making progress.
While there were few moments of cheer in 1999, with the new year all the hard work paid off. Remember that with a large fleet (212 three car sets is the minimum quantity) it takes a long time to implement modification packages.
Under its contract Metrocare started earning bonuses at a MDBF of 15,000km and by mid 2000 reliability growth was ahead of schedule at 20,000km.
This graph reminds me strongly of the Class 319 EMUs for Thameslink where GEC Alsthom introduced new traction technology. These too performed poorly initially as the kit was shaken down. Chris Green, then Director Network SouthEast, had reached the point where he had gone public with his dissatisfaction, only to roll up at a crisis meeting to discover that the reliability breakthrough had been achieved the month before.
Of course, reliability is one thing, availability is another. Here, Metrocare has been fortunate. Because the Northern line was not resignalled as expected, the daily service requirement was cut to 84 trains plus two spares out of the 106 train fleet.
On the day of my visit actual availability had been 90 trains and in the Summer of 2002 with changes to drivers' rostering, 91 trains will be required for daily service.
During my visit Metrocare showed me the four week/12week availability graph for the year April-April 2000-2001. and very boring it is, with the 12 weekly average running around 99.5% and the four weekly bottoming at 99% twice and hitting one 100%, a couple of 99.9s and four 99.8s in the 14 periods shown.
One advantage of the reduced service requirement is that you can have a ‘hot spare' available at the depot. Combine this with the extensive redundancy in the 95 Stock's system, plus the Train Management System (TMS) and you gain a high degree of resilience.
If a train has a technical problem, it is likely to keep running. The TMS warns the driver and the hot spare means you can pull the train before it fails and replace it seamlessly with the hot spare.
High train mileage on the Northern Line has also accelerated development. The 84 trains daily requirement equates to 10.8km/year or just over 200,000km a week.
In September and October 2001, over four successive weeks, the MDBF went 50,000, 80,000 100,000 and, in the week of 8 October 200,000km. The final figure represented one failure that week and Clayton had set his staff the new target of MDBF of infinity – a failure free week.
But in the two weeks after this purple patch MBDF was back with a bump to 15,000km and 25,000km. What caused the abrupt reversal? Old fashioned mechanical engineering.
Doors on the 95 tube Stock are driven by a rotary actuator. Rotary actuators are tough and rugged, and on the Northern Line stock a shaft runs in a simple plain bearing. The tolerances on this bearing are fairly tight. After a frosty night in the sidings with the train heating off, the metal contracts, further reducing the tolerance, the grease is more viscous, ‘stiction' is increased and a door won't work first thing, failing a train.
This highlights the challenge faced by Metrocare's continuous improvement programme. Modifications now have to deal with very few failures, even the target MDBF of 30,000km is only seven failures a week. But in the case of the doors, there are 12,000 actuators.
As a result, the trains that fail are being targeted, rather than a campaign modification programme. And, of course, it could be that the heating had not come on in a coach with an actuator that failed.
Ian Clayton emphasises that life was not easy when the contract started. The existing trains had to be made more reliable, while the staff at the two depots where being transferred to the new owner and the facilities upgraded. When the new trains arrived there was the pressure of commissioning and managing the inevitable modification programme. Simultaneously, the drivers and maintenance staff had to get up to speed on the trains' TMS, diagnostics and communications facilities, all while running two fleets in parallel.
New technology and an adaptable work force has helped. Forty years ago, I can remember the first electronic control modules arriving on depot, followed by the realisation that you couldn't test or repair the damn things. At Golders Green Ian Clayton has set up a small electronics workshop, with in-house trained technicians, which can make the ‘first cut' on failed modules and hopefully eliminate the dread acronym NFF (no fault found)
As part of the Depot modernisation Metrocare installed Machine Vision which measures wheel profiles, brake block wear and collector shoe wear as each train passes over a pit. This has not had a happy life to date. Just as the results were looking promising , the pit was flooded which did the electronics no good. Now it has been recommissioned and the system was being revalidated at the time of my visit.
A recurring problem with new generation trains has been the inability of some drivers to cope with the TMS, let alone exploit its diagnostics capabilities. As part of the Northern Line deal, Metrocare has what it terms ‘call point staff' at Kennington and Euston and in the Coburg Street Control.
These are technicians who can coach drivers and operators through the use of the TMS. At Coburg Street a Metrocare technician sits alongside the line controllers. Clayton thinks such proximity essential because experience has taught him that fault information has a short life ‘before it whisks away never to be seen again unless it's captured at that instant'.
A link with the Metrocare computer allows the technician to capture an event, say a sluggish door, and set up a works number in the computerised maintenance system. Then, when the train arrives at the depot for service, these numbers are called up and entered on that night's work schedule for investigation.
While each train still has its fault reporting log, the call point staff make data capture close to real time.
This ability for a train to detect an incipient fault before it becomes a show stopper has been the holy grail of the TMS revolution – and it is starting to pay dividends. If a train have a problem in service, the technician can offer comments and advice though the Line Controller. Here too something has been learned. Traditionally Line Controllers were ex drivers with extensive traction knowledge and able to advise drivers in trouble. Northern Line wiped out this data base.
A common problem with all the new TMS fitted trains has been information overload. Almost overnight the industry has swung from ‘driver as robot' who can't be trusted with information, to a data rich cab environment requiring understanding and judgement. The TMS throws up a lot of error messages, but because of the extensive redundancy, an error message does not necessarily mean that a train can't run. For example, the traction packages are conservatively rated, lose one and not only has the train not ‘failed', but it can still run to time.
More thought has had to be given to the fault messages displayed to drivers on the TMS screen. Early on, for example, the trains had problems with the air suspension.
When the TMS flagged up suspension failure some drivers immediately took the train out of service. In fact, as other drivers soon realised, all that happens is that the affected vehicle runs quite happily on its rubber bump stops, with a slightly degraded ride.
Metrocare's Engineering Manager Steve Mitchell uses Northern Line to get to work. He saw this ‘non-critical failure' problem at first hand in the early days when a driver took a train out of service because the door chimes still kept chiming with the doors closed. This sparked an analysis of how a technical failure becomes a delay.
Inside the TMS there is a host of decisions being made in the event of a failure. In particular, what does a particular failure do to the train, is there redundancy and, ultimately, what message to give the driver.
This was unknown territory for train builder and customer and the original help text messages for the driver tended to say ‘do something and contact the line controller'. A classic example was the warning that the de-icing fluid tank was less than 10% full, which flagged up as fluid sloshed around.
This warning message, too, added ‘contact line controller' even in high summer. The answer was to change the message to say that during winter months a note should be made in the logbook for the next examination.
All the ‘contact line controller messages' were clogging up the train radio channels. This meant that the driver who really needed help couldn't get through.
As a result a team from Metrocare, LU's Operating Department and the 95 Tube Stock Project Team went through the 2,500 events that could trigger messages and cut the number the driver needs to see to around 500.
Now the 500 messages are being reviewed and with trains increasing reliability, nearly half are effectively redundant because those particular faults are so rare.
Whereas the TMS capabilities of most of the new generation main line electric multiple units are barely being tapped, the 95 Tube Stock is a smart train in a smart environment. Ian Clayton reckons there is a higher level of acceptance of computerised maintenance management on the Northern line than he has seen in the other industries in which he has worked.
And there is more to come. Due to problems with the radio system, the e-train concept has been delayed. This will see each train's TMS talking directly to the depot by radio. A fault on the TMS will be sent to a ‘data warehouse', which will help maintenance planning, but it will also be able to interrogate this data.
Thus the record could be used to mimic switch settings in the cab and, ultimately, a technician in Control could ‘look over the driver's shoulder' electronically and advise on fault recovery. The same system could also be used for train preparation, at least items not requiring physical inspection.
Hardware for the e-train systems exists, the software has currently been redrafted and is now at the acceptance and integration test stage. The data warehouse is ready. All that remains is to write some radio software and the next step forward could be operational in August.
Train service provision depends crucially on equipment suppliers who represent 65% of Metrocare's cost base. There are fixed annual payments to the major suppliers such as Vapor (doors) Brecknell Willis (shoegear) and Westinghouse (brakes). They, in turn, have service provision contracts with Metrocare, which include reliability guarantees, supply of spares and repairs, equipment overhaul and obsolescence cover.
There is also a labour hours commitment for maintenance tasks. During the train bidding, sub-contractors were asked to nominate the hours needed for key tasks. There were some stressful encounters, including the use of brute force, when suppliers were subsequently invited to Washwood Heath, shown the 95 Tube Stock and asked to validate their offer. Now, if the work takes less time there are bonuses to be won.
For the existing staff, the change from 59 to 95 stock was a huge challenge. There were no forced redundancies but skills continue to improve. According to Clayton he would not have thought the staff capable of the work they are now doing. And now he is tapping their abilities with a Continuous Improvement Programme.
Its initial project was to look at the B2 exam with a team of engineers and shop floor staff. Analysis showed that staff walked six miles during the exam! A restructured package reduced this to a mile. More importantly, it should reduce the time taken from a week to a weekend, which will be essential when the 96 train timetable becomes reality.
This to Golders Green reinforced my long held view that manufacturers should maintain their equipment. The performance figures to date support this prejudice and I hope to revisit Metrocare to report on the daily work of the depots, including the ultra-modern Stratford facility for the JLE fleet. And, of course, the experience should stand Alstom Traincare in good stead as Pendolino comes into service. Memo to Chris Green: remember 319 when Pendolino stutters.
Depot FacilitiersGolders Greenl Wheel Lathes l 4 Lifting Roads l 31 Stabling Roads –4 Sidings –7 Pit Roads –3 Side Pit Roads l Electronics Workshop l De-icing Facilities Mordenl Paint Shop l Two Wash Plants l Machine Vision l De-icing facilities l 49 Stabling Roads –4 Cleaning Platforms –7 Pit Roads –5 Side Pit Roads
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