A Collision in UK on ETCS Level-2 has big lessons for Indian Railways

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Source: “Crash of two commuter trains in UK on 21 Oct 24”

We are adding more items of same vendor in to signal and in rolling stock. Can we just work on ‘trust us bro’ principle? How would IR get access when accidents happen or IR continues to allow giving self-certification to the vendors while imprisoning its own employees?

A senior retired officer shared a note and a news of a #collision of two commuter trains in the UK on a single line section.

What Happened

Here, #Train X was standing on the mainline and waiting for track ahead to clear. Train Y coming from opposite direction was to be placed in a passing loop. This train Y travelled almost 900-1000 metres over and above the point where it should have stopped in a loop and reentered the mainline and collided with Train X. One person died while many were left injured, some of them seriously.

Location

Talerdigg is at a slope and the Cambrian line where it is situated has steep gradient of about 1 in 70. The Cambrian Line has been in operation since middle of 19th century – “Newton and Machynlleth Railway-Wikipedia”.

Collision on ETCS Level-2 Line

Indian Railways (#IR) also operates steep lines like those South East (towards Igatpuri-Kasara) and South West (Towards Pune through Khandala-Lonavala) of #MumbaiDivision of #CentralRailway and these grades are almost 1 in 40.

On the line, #ETCS Level-2 protection is available since 2010s. This #signalling level gives incab signalling and fixed mast signals are not needed. The #brake-systems on trains had wheel slide protection and provision of sanding. It was found that when #Train Y was proceeding towards its loop, driver slowed by applying service brakes. Wheel slide started to occur, but sanders were not working. The train continued to slide as it entered and exited the loop, finally travelling almost 900 m and crashing in to train X.

Rail-wheel adhesion was measured and found low due to leaf fall.

Lessons for IR

Indian Railways is forcing a ₹10,000 crore #Tender for loco #Kavach module through #CLW as this #accident happened. #Accidents like #Balasore show that when the #signal-circuits are tinkered with, Kavach gets impaired as Kavach needs data from #interlocking to process and act.

Now, if interlocking is set right would Kavach still be needed? #Railway officers across departments say if Kavach still needs data from existing signalling system, then Kavach system is just over-hyped and over sold by few railway #vendors. They tell that Talerdigg accident a fortnight ago in UK was supposed to be protected by ETCS Level-2 which is best in class signalling. One can argue that small and light trains will lose adhesion unlike IR, but experts argue that issue is not specifics of the line or the rolling stock. Issue is that every signalling intervention has a limitation. To say Kavach will eliminate railway accidents is not correct.

For example, see this: “Uneven loading in freight trains major cause of derailment-Railway Board” which quotes the CRB, “According to #CRB Satish Kumar, there have been six cases of #derailment of BOBYN wagons between April 2023 and November 3, 2024, and in all these cases uneven loading was found to be the cause of derailments.” What would Kavach do in this? Also in recent accidents like #Balasore to #Gonda to #Chennai, Kavach could not have prevented these accidents.

Coming back to #Talerdigg, the investigators note, “There is conflicting evidence relating to the #speed of the trains at the point of #collision. Initial analysis indicates that train 1J25 was travelling at between 24 km/h (15 mph) and 39 km/h (24 mph), while train 1S71 was travelling at around 10 km/h (6 mph) in the opposite direction. #RAIB is continuing to analyse evidence relating to the collision speed, which remains an area of ongoing investigation.”

Also, investigators are looking in to #data recorded by the trains.

This brings to fore a very serious limitation imposed on IR #signalling and #rollingstock. The entire electronics, programming in signals and rolling stock is with #vendors and IR treats them as #black-boxes. We are adding more items of same #vendor in to signal and in rolling stock. Can we just work on ‘trust us bro’ principle? How would IR get access when accidents happen or IR continues to allow giving self-certification to the vendors while imprisoning its own employees?

Lessons for IR-Be Transparent, Act Now and Avoid Taint of Scam

Excessive push for Kavach will suck funds from the country without delivering a solution. See, “CLW’s Kavach Tender : Does this explain the inexplicable extension?” of 29 August, 2024.

We had teased the matter on 22 August-

It is reported that reverse auction (#RA) has happened and orders far in excess of the participating vendors’ turnover will be given for fitment in locomotives.

This has baffled officers. Firstly, how can firms deliver more than their #capacity in one year? How can all the items procured by fitted and commissioned in 12 months? Does IR plan to withdraw 10,000 locomotives in one go? We wrote, “Total #capacity assessed by #RDSO is about 2,300 per annum of these vendors put together. However, under the given conditions, 10,000 kavach have to be supplied in one year.”

This clearly looks like a #scam. IR does not have capacity including using #TPIs to even inspect the supplied items. So what is the ‘scheme’? Officers say that making an item out of Kavach system, this is plan to saturate the market early. Also, vendors will just manufacture and dump the material, and be eligible for equivalent of on-account payment which in this case will be more than their annual turnover.

We had very clearly explained in our 29 August, 2024 article – “CLW’s Kavach Tender : Does this explain the inexplicable extension?” – quoting signal experts that:

  • Not just that, the #version which will get implemented on #IndianRailways is #Kavach-version-4.0 while the one which has been tested is #Kavach-version-3.2. The very fact that #version-number has changed from 3.2 to 4.0 (i.e. not to 3.3) indicates that the difference between the versions is substantial or major in nature or in other words the change would require major design change. Now, how can design of #loco-units be frozen before #Safety validation of composite system which will take longer than one year in which these loco units have to be supplied?

We asked several senior #rail-experts. We got following summary on core issues:

  • There are major #hardware and #software changes between version 3.2 and 4.0 of Kavach. The trial were done on version 3.2. These were limited trials and had few open issues. However, as the #system is still a layer on top of existing signalling system, that is if there is Balasore type of error, then with trains running in close proximity (i.e. train separation smaller than braking distances-which incidentally are uncertain due to #BMBS issues), then Kavach system is hardly of any use. This every railway officer understands.
  • So, #Signalling-engineers are not able to freeze the #specification and they came up rightly so with version 4.0 of the specification of Kavach. The extent of changes call for #revalidation by safety assessor for #SIL-4 certification. Thus from #SIL standpoint version 3.2 and version 4.0 represent two different products. So while gaming the system and claiming that the #vendor status of version 3.2 shall apply for tender on version 4.0 is misleading and dangerous. It appears that CLW objected and was overruled. Now who could have over-ruled CLW?

Hurry to do the enormously #big-tender which will just block the capital and deliver no immediate or mid-term benefit is very suspicious, especially when more vendors are in offing and basic principle of Kavach is being questioned.

Please note that the #theory propounded in recent #BagmatiExpress-accident was that it was a #sabotage where power tools were used to dismantle the track components. This is what we had mentioned when Mr #AKKhandelwal and Mr #AshwiniVaishnaw advertised for an old type of #rail-fastening as a new fastening system which would have reduced the vendor base while making it very easy to sabotage – “Khandelwal-Sense at Work: An Expensive Fastening System from Small Vendor Base-Atleast not for Railway Safety”. Bagmati Express #derailment sealed the fate of the ‘new’ fastening system.

Let us not forget that most of the #mega-tenders like greenfield loco factories in Bihar have failed to deliver promised benefits-such mega tenders is what Khan Market Gang (#KMG) excels in.

Talerdigg accident where ETCS Level-2 was available, tells us that #Kavach is not single solution to prevent accidents.

As #PMO has shown sagacity to review the irrational decisions taken by his #RailwayBoard and reversed many of them, Kavach should be put to assessment by safety experts from outside the Railway Ministry. Perhaps we need another #Kakodkar Committee type assessment of Kavach.

It is time to act urgently and take a strategic pause. The monies can be put else where in national economy instead in hands of few vendors or companies to make a product which will only add more complexity, add more failure modes, reduce punctuality and make system even more dependent on few vendors while #railways will perpetually bleed in Annual Maintenance Contracts (#AMC). We are sure this cannot be the objective of the Government.