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Making the track layout and signalling more driver friendly has not been difficult – simplification is the key
Such was the scale of death and destruction at Ladbroke Grove that the horror has tended to overshadow the cruelly simple causes. The HSE is pressing on with prosecutions under the Health & Safety at Work Act and the Crown Prosecution Service has been invited to take another look, but it is hard to see who could be held to account.
In his recommendations Lord Cullen enjoyed the benefit of 20/20 hindsight. But when they were implemented, features like bi-directional signalling and automatic route setting were a step forward in the drive to improve operational flexibility and with it reliability and capacity.
That Paddington was difficult for drivers is not in doubt. The number of multi-SPADed signals confirmed this. And the root cause of the accident could be summed up as a layout that expecting too much of drivers' undoubted abilities in route learning and signal reading.
When an inexperienced driver, inadequately trained, was allowed to drive in and out of this complex station area, this expectation may, I emphasise ‘may' have led disaster. Or Driver Hodder may have been mislead by ghosting due to the low morning sun. We shall never know.
What were the problems drivers faced? Signal sighting was impaired by the overhead lines, but met Group Standards. The Automatic Route Setting was too clever by half, sending drivers off on a mystery tour of bi-directional working in its search for ‘two greens'. One driver told the inquiry that he drove from signal to signal at 15mile/h in these circumstances.
Flank protection was not provided for SN109, the signal passed at danger. But flank protection was not favoured by the HMRI which prefers separation.
It was, if you like, a case of creeping normalcy. As their task got harder, most drivers coped, as they always have and the demanding became everyday. As a signaller commented to the inquiry, all they had to do was obey the signals. We know better know – except First Group which still seems to hanker for a draconian one-SPAD-and –here's-your-P45 approach
In the light of the Inquiry the Paddington approaches have been remodelled. The safety case for the new design is imminent. The result shows what happens when you go back to first principles, do not assume that the driver is omnipotent and infallible and use the full capabilities of Computer Aided Design and simulation.
hese changes to the signalling over the two miles out of Paddington will allow the restrictions on operation imposed after Ladbroke Grove collision to be lifted. Currewntly the situation is: Line 1 closed Lines 2 & 3 uni-directional Lines 4, 5 & 6 bi - directional
Total cost of the track and signalling work is estimated at £29m
A number of detailed improvements have already been implemented.
TPWS has been fitted to 82 signals plus platform buffer stops in the station and the Thames Trains fleet is TPWS equipped. In parallel, speed limits have been revised to match real life over-laps. Great Western and Heathrow Express cabs are already fitted with ATP.
A highly visible change is the fitting of large line identification plates above the signals on the gantries across the six track section. Drivers had told the inquiry how they had to count across from each side to check which signal applied to the line they were on. The overhead line electrification equipment has also been realigned to improve sighting. Potential distractions, such as speed boards, have been removed from the track.
In Slough IECC a SPAD alarm has been fitted since last August. Similar alarms should have been installed at all IECCs by now.
However, when I asked at the Railtrack presentation on the changes what the IECC operator was supposed to do when the alarm went off, the briefing team went a bit vague. One of the remaining big weaknesses in the railway is the ‘old railway' attitude among signalmen, some of whom are even embarrassed by the requirement to use the phonetic alphabet. In contrast, when I booked a cottage from a large rental agency recently, the code for the property was repeated back as Golf Lima Papa.
At this year's National SPAD conference I asked one speaker whether we would see the correct use of ‘fife' and ‘niner' in safety critical communications. ‘We are still trying to get them to use the phonetic alphabet' he replied. Not good. Still, correcting a surprising omission, a new manual for signalmen (working title ‘Signalbox Etiquette') detailing what constitutes professional working practices, is in draft form.
But back to the SPAD alarm procedure. Given the criticism of the signaller at Slough in the Cullen Inquiry, my reaction would be bang the ‘all signals to red' button first and think about the consequences afterwards. I do worry about long serving railway staff who try to keep the service running rather than going by the book and causing disruption.
Since the Inquiry Recommendations were published, Railtrack and Westinghouse have been developing the resignalling needed to allow the station approach lines to be brought back into full use.
A big plus has been the availability of virtual reality signal sighting simulation which is linked to computer aided design and a digitised model of the rail infrastructure. Such is progress that you can run the simulation off a high-ish end PC.
You design your signalling installation, say a gantry with multiple signal heads and feed the data into the simulation comes into two parts.
First of all, in plan view, you can see the line of sight of each aspect. This has been used to test the proposed resignalling which is aimed at allowing all the lines into the station to be used. Second you can ‘drive' the route and see both signals and infrastructure as a driver's eye level view.
Central to the resignalling is the use of the Bombardier fibre-optic multi-aspect signal head. This has a single searchlight which can show red green or yellow aspects. The signal lamps are in a remote housing with the light transmitted to the head by fibre optic cable.
This configuration means that a gantry mounted signal has its single search light below the OHLE. One of the theories is that the red aspect at SN109 was obscured when the ghosted yellow could be seen. With a single searchlight the risk of misreading is reduced and all three aspects can be displayed in the same optimum position.
On top of which, since the colour is determined by the signal lamps, the lens of the searchlight is clear, eliminating the risk of ghosting altogether.
Not only is it a better signal. The lamp housing is located conventionally in a cage with access for maintenance. Periodic cleaning of the lens is the only attention required by the signal head. Less maintenance means less risk to maintainers.
Bombardier's fibre optic head is already in use at Leeds , where similar sighting problems emerged following resignalling and electrification. Under the Paddington changes all six-line gantries will be fitted with the new design, totalling 50 heads. Westinghouse is responsible for the signalling installation work.
Clearly with the new heads the Paddington approach reverts from four to three aspect, with bi-directional signalling restored. Andrew Simmons, Railtrack's Head of Signal Engineering told me that the revised layout returned ‘full functionality' to the Paddington approach.The change to three aspect signalling should not affect capacity. In fact Simmons reckons that the change should improve performance because drivers will encounter more green signals.
In the up direction speeds have been reduced from 90mile/h to 60mile/h before the start of the bi-directional six tracks. There is a further reduction to 40mile/h before the station throat. This extends the running time between Paddington and airport junction by around 23 seconds.
Automatic Route Setting was criticised in the inquiry for confusing drivers through the wide range of routes it could provide at random. This meant that ‘route knowledge' could not be acquired.
To remedy this, the ARS at Slough IECC has been reprogrammed to reduce the scope for alternate paths. Instead of being allowed to hunt for green signals at will, the ARS software can select only from a set of timetabled paths.
In future, signallers will now be expected to set routes in the event of service perturbations. This is a wise move, since it retains, or reintroduces, what used to be a vital signalling skill. ARS will now do hum-drum, the Mk 1 human brain will handle the difficult stuff.
Under the new regime, Lines 1 & 2 will be predominantly used by ‘down' trains, Lines 3 & 4 for ‘up while 5 will be ‘down' and 6 ‘up'. Bi-directional working will not be used in normal operation.
Finally, flank protection has been reconsidered and will be provided for SN109 onto the down relief line. The effect of a SPAD at SN109 will be to turn the signals protecting the adjacent line to danger to minimise the risk of s side-swipe collision.
Westinghouse will be responsible for the design, installation, test and commissioning of the work. This will include alterations to and testing of 6 SSI and associated location design. Associated new TPWS will be installed at some locations and the TPWS that was commissioned in October 2001 removed where it will become redundant. In addition to the removal of redundant signals and installation of new heads new ATP equipment will be installed to match the changed configuration of existing equipment altered where required. Final Commissioning has been scheduled during a four day blockade starting on 27 December 2002 .
Sir Peter Parker was the first British Rail Chairman I got to know really well. It wasn't difficult, ‘PP' was the most approachable and warmest hearted of men.
And he was the same with everyone. For a Modern Railways article I shadowed him on a two day tour of the Northwest where he met local authorities, passengers' representatives and railway staff at all levels. And all warmed to his natural sincerity and charm plus an inexhaustible enthusiasm for the railways .
In one mess room a dour faced phalanx of drivers was lined up on once side of a table, a chair for the visitor on the other. PP said afterwards it was a bit like ‘And when did you last see your father'. But as ever he won round the men who were determined that they had seen it all before.
During his chairmanship I misjudged him grievously. I thought he was too nice to deal with weasely politicians and civil servants. Why wasn't he more aggressive? He would welcome Government initiatives that looked horribly like threats to the future of the railway. In a Modern Railways editorial we said that he would find some way of welcoming a proposal to shut the whole network down.
But in my immaturity I did not appreciate what he was doing. As he embraced initiatives like the Serpell Inquiry, he knew that the BR Board's machiavells would smother them with helpfulness and see them off.
Meanwhile he was working to establish a quasi contractual with Government. Tell us what you want railways to do, give us a contract to do it and we will deliver was the message. Or in PP speech ‘contracts quicken, subsidies sicken'. He knew who this approach would really appeal to: he once said ‘the Department of Transport is transparent, you can see right through it to the Treasury.
And it worked. While the second half of the 1970s were not an easy time for BR and its Chairman, he and Chief Executive Bob Reid were also looking to the future. Asked how he would judge whether he had succeeded as Chairman PP once said ‘I will have succeeded if my successor as Chairman is a railwayman.' And Bob Reid did just that.
Older and hopefully wiser how do I rate him among the BR Chairmen? Undoubtedly in the top three with Bob Reid and Bill Johnson and probably shading Johnson for second place because both railwaymen came to power in propitious times whereas Parker had to battle with Whitehall and the rail unions.
We last met at the ‘Farewell to BR' thrash last year. When he came up with that familiar beaming grin and his habitual greeting ‘wotcher chum', it was as if he had never been away. That was PP. A good chum and a great railway chairman