[SillyMaxwell]

Originally Posted by Rajeevraj

seems that the point switch back to the main line after the goods entered did not happen at the mechanical level but the electronics indicated it had happened and the signal changed to indicate clearance for the main line.

This is better version I read so far on this, television news is worse. However, from my background, what I know is, signal could not be green when the tracks are short. When a train is on the track or any sizable conductor on both tracks, it makes the signal to default red. This is a major contributing factor to Indian railways fail safe electric relay design. It would be a very complicated relay circuit design, confidentially kept, to tamper. Not denying it cannot be done though. The probability of anyone capable of doing it will be slim to none. If the point didn’t came back to the main line that signal should still be short as the point was associated with the circuit on which the train was already there. All my knowledge on this was telling that signal being green for the loop line where the train was there could never happen.

I think we have to wait for the official statement on what happened from IRS top brass. Hope they tell the truth and steps to make this never happen again.

[fhdowntheline]

Inter city train travel is not the same as intra city travel. Overcrowding has to be eliminated at sone point. Who is going to take responsibility of unidentified passengers in an accident or even a criminal situation in a running train? Just as we have cleaned up our railway stations for a better experience(major ones at least), this has to be the next step. Basic travel comfort is the right of a fare paying passenger. That is the sort of social discipline ( or lack of) I referred to earlier. Other things too: - Do you ever see people crossing rail tracks on foot in other developed countries? Then what is it that ails our society?

[thanixravindran]

Originally Posted by Senotrius

Why are these kind of accidents lesser in South India? In Kerala may be cause the total number of lines is so less I feel( it's literally one major direction from north to the south). I cant remember a rail accident in this state in recent memory. But other southern states are larger. Does anyone have an explanation? Majority of accidents, like aviation accidents, are human error eventually.

As others pointed out, the lines in central and Northern parts are quite busy. A major factor is the freight movement from natural resource rich central part of India (mines) towards the east (Howrah) and west (JNPT).

In roadways, we have implemented the GQ 20 years ago and with saturation of railway lines, the frieght traffic moved to roads from railways. Dedicated Freight Corridor (DFC) was envisaged more than 15 years but even the east and west corridors are not fully operational yet. I for one was betting on this as game changer for railways for several reasons - Frieght revenue, environmental impact, reduction of load in highways, better passenger trains. Hope that project is accelerated like we did for roadways with private partnership.

What we see is only the operational side of Railways but they do have engineering and research wing with excellent quality who adopted continuous improvement model and they keep updating which won't be visible to us. But it's time Indian Railways is broken up to focus on its core of expanding corridors and relieve the operational burden. This needs some sort of financial engineering from the government but first it needs the will power.

[AirbusCapt]

What exactly happened? Simple: the express train travelling at 127kmph entered the loop line which was already occupied by a heavy ore train. The locomotive jumped over the roof of the guard cabin crushing it and then over the boxn wagons. The inertia was so great that 22 coaches derailed and some coaches were thrown across to the opposite track. Almost at the same time the yeshwantpur express was crossing on the other side and by a small slice of good fortune only the last two coaches derailed on hitting the coaches from the derailed train. The yeshwantpur train then continued to its destination (after thorough checks) at a reduced speed.

What is the root cause of this disaster? Prima facie, the express train put on to the loop line with a green signal. If the plan was to run the train through the loop line, a double yellow signal would be set to ensure the train crossed the loop at a much slower speed (to prevent derailment on curves, possibility of people near the tracks etc).
When the loop line was occupied the interlocking signal mechanism shouldnt allow the next train to enter the loop line.

Was the system forced open by a terrorist sympathizer? Or was there some hidden bug in the interlocking system which can cause such issues? These are questions which the CBI enquiry will hopefully answer.

[aaggoswami]

As per the below article a Railway official had earlier indicated that there was some concern with signalling system.

Source : https://www.thehindu.com/news/nation...le66930016.ece

As per the article in the link above, an accident was earlier averted by an alert locomotive pilot.

[sagarpadaki]

One aspect that is not clear to me is how did the Yesvantpur train, who's last 2 bogies detached and derailed, continued to move for a couple of kms before being stopped? If I understand correctly, in case there is disconnection in the air brake lines between the engine and the guard, the emergency brakes are automatically applied and train will automatically come to a halt. A fully loaded 22 coach LHB rake train can very well come to a halt within 1 kms when brakes are applied at MPS.

[Tucker48]

On an average more than 20,000 people die in India every year in all rail accidents. Approximately 30% of that in derailments. Very bad numbers in my opinion.

[SedateGuy]

Originally Posted by Tucker48

On an average more than 20,000 people die in India every year in all rail accidents. Approximately 30% of that in derailments. Very bad numbers in my opinion.

Human life is not valued in India. You are from Mumbai, you must be reading on how many die on the local train tracks everyday, yet they roll on merrily.

[jigar1791@gmail]

Originally Posted by Tucker48

On an average more than 20,000 people die in India every year in all rail accidents. Approximately 30% of that in derailments. Very bad numbers in my opinion.

The numbers are huge, and it's saddening to see untimely loss of human lives for no fault of theirs (for most part, leaving aside suicides and death defying stunts etc).

However, let's draw some parallels -
1. On a daily basis, IR's pax count is ~10 million, or say, 1 cr. Meaning - about 1% of India's population travels in it's trains everyday.
2. Annually, total pax count will be about 365 cr (keeping 1 cr as the base count), including both - intercity and suburban operations.
3. IR operates about 18,000 daily intercity trains and suburban trains in 12 cities, owns about 64K kms of tracks, for both - passenger and freight operations.
4. IR's ticketing is the lowest(?) in the world. Per km rates for SL is <1/-, that's the way most Indians travel. Even suburban tickets are priced dirt cheap to allow all people from all sections of our society to travel.
5. Even with such massive scale of operations and handling high volume of passengers at such low costs, IR has impeccable safety records if we compare with any other well-organized railway system around the world.

No, I'm not saying accidents don't happen, people don't die on IR's tracks and stuff, but, we somehow have to give credit to IT as an organization to manage, keep and run such mammoth operations (without much technology) with high safety standards.

Let's value IR and it's service to our nation, criticize it where it is needed.

Originally Posted by SedateGuy

Human life is not valued in India. You are from Mumbai, you must be reading on how many die on the local train tracks everyday, yet they roll on merrily.

I live right next to Borivli Railway Station, one of the busier stations on Mumbai's Western Railway corridor. The station sees huge footfalls - it's a hub for suburban services and a major stop for all long-distance trains originating out from Bandra/MMCT.

Believe me, there has been a considerable reduction in deaths on our suburban trains (here again - I'm not saying it's 0 death network, but there has been a visible reduction).
There are steps taken by the authorities to prevent/reduce/curb deaths on local trains, and it's efforts are seeing results -
1. Shutting off of all fataks or railway crossings(east to west crossovers on railway tracks) and building flyovers for all suburbs
2. Educating the passengers on hazards of rooftop travel (which has stopped on account of 25KV AC overhead lines), footboarding and stuntmanship.
3. RPF and GRP do seem active to control crowds (or atleast, on BVI they do)
4. Increase in suburban services - a decade ago, we had a Virar service at an average interval of ~10 mins, that has reduced to ~3 mins as on date. Though capacity addition hasn't been in proportion to population growth in outer suburbs of MMR (beyond Bhanyandar upto Dahanu), yet, significant rise in services have resulted in lesser (to some aspect) crowds in locals.
5. Newer rakes procured under MUTP with better ventilation, jerkless operations have aided passenger travel experience.

Yes - human life may not be valued in India, it's visible even in the corporate world, yet, it's not 100% Railways' fault everytime.
Agreed, periodic maintenance should be more frequent, rolling stock need to be more advanced (LHBs are, death toll at Balasore would have been more if the rakes had old ICF coaches), state-of-art signalling systems should be installed etc etc. But, we should also look at the other side, where progress is happening and it's visible.

[AutoNoob]

Originally Posted by AutoNoob

What is the ‘interlocking’ system in Railways, a change in which led to the Coromandel crash?

Source: Indian Express

Originally Posted by Rajeevraj

The core reason seems to be coramandel express entering the loop line at high speed. Why that happened will be the focus of the detailed investigation. The signal had to be for the mainline as there is no way the signal actually could have been for the loop line as the goods was already there.

Originally Posted by Vipin Kumar

By all commonsense about even automated signalling system, a signal to enter loop line with a reduced speed should be reflecting in the previous two signal points. Will it be a run-through green on the outer signal points if a train has to enter loop line only? Or, can a loop signal be given when a train is already standing on that particular loop? Shouldn't these be all interconnected?

Originally Posted by SillyMaxwell

what I know is, signal could not be green when the tracks are short. When a train is on the track or any sizable conductor on both tracks, it makes the signal to default red.

Originally Posted by AirbusCapt

What is the root cause of this disaster? Prima facie, the express train put on to the loop line with a green signal.
When the loop line was occupied the interlocking signal mechanism shouldnt allow the next train to enter the loop line.

Was the system forced open by a terrorist sympathizer? Or was there some hidden bug in the interlocking system which can cause such issues?

Quick fix for green signal to Coromandel likely cause of Odisha train accident

Malfunctioning level-crossing gate may have led to ‘tampering’ of ‘location box’.

Source: Indian Express

The sequence of events leading to the crash and derailment of the train, officers said, was probably triggered by a malfunctioning level-crossing gate — its boom barrier was not working — before the station. In one version, the barrier remained raised, and in another, it did lower but the signal continued to be red. In both cases, it was a problem, they said.

For the officials manning the Bahanaga Bazar station, Friday was just another day at work. Their job was to just let the Coromandel Express “through”, which takes a few seconds. So, to get around the problem of the boom barrier, some Railway officials or the signalling technician on the ground “looped” the ‘location box’.

A ‘location box’, typically placed along tracks, holds a junction of connections to the point motor (the movable piece of rail that physically guides a train to its designated track when there are two divergent tracks), the signalling lights, the track-occupancy detectors, and virtually every critical piece that makes the ‘interlocking’ work seamlessly. Interlocking is a crucial safety mechanism and ensures trains move without any conflict with each other, preventing accidents.

By looping the location box, the technician achieved an “all clear” signal for the Coromandel Express, overriding the fail-safe logic manually. In other words, the technician manually “completed” the circuit, bypassing certain nodes in a manner that the system would not recognise anything was amiss.

“This would have gone undetected but for one thing. The point, 17A,” said a senior official who is in the know of things. This manual act did not relay to the system that while the “all clear” signal was achieved, the point remained directed towards the loop line.

The due process requires signalling technicians to first furnish a “disconnection memo” to the station master, who would then authorise switching off the interlocking system. This would mean switching to manual mode: the signal would have to be flagged manually, and for that the point would have to be set and locked manually. For longer duration maintenance jobs, the station master would effect a “traffic block” when no train operation is allowed for a while.

the Railways’ signalling department had given a “dissent note”. “The point of derailment (is) before the level crossing gate no 94 that is before point 17A,” the dissent note said. It said the data logger — the digital recording of the live status of the interlocking system displayed at the station master’s room and elsewhere — showed everything was fine.

So, this is intermediate analysis, final analysis will take time.

[Tucker48]

Originally Posted by jigar1791@gmail

....

Let's value IR and it's service to our nation, criticize it where it is needed.

Yes, I'm criticizing it and I don't see your statements convincing me otherwise. What are you comparing this data with? Where is the data for other countries? Or other modes of transportation. More than 15 lakh employees work directly for Indian railways. Definitely it's mammoth.

[tharian]

Originally Posted by AutoNoob

Quick fix for green signal to Coromandel likely cause of Odisha train accident

Malfunctioning level-crossing gate may have led to ‘tampering’ of ‘location box’.



So, this is intermediate analysis, final analysis will take time.

Question is, why did they have to do this when they could have done it manually and let the train pass with a green signal by hand.
The train will loose time as it has to slow down and cross the signal and section in slow speed. When the LC doesn't work, the LC signal will remain in danger for which the gateman has to show an all clear , but the train would have slowed down before that itself because the signal before that will automatically be at caution.

Why this short cut work around is what I don't understand. Trains are running delayed all over the IR network everyday. This was not a Rajdhani or Shatabdi or VB either for them to take a risk.

[itwasntme]

Originally Posted by AutoNoob

Quick fix for green signal to Coromandel likely cause of Odisha train accident

I dearly hope such shortcuts are a total outlier, and not being carried out with the implicit/explicit connivance of station masters across small stations.

They are usually under severe pressure to keep all trains, and especially the express / premium trains running smoothly through their sectors.

[Thad E Ginathom]

Can someone give me a quick "replay" on one thing that I recall from early news coverage, please?

There was something a red warning light that came on for five seconds. What was that about? And what's with a warning light that is going to be missed if someone is even rubbing their eyes?

Was the five-second duration a malfunction in itself, or are the staff really supposed to notice something barely more than a flash?

Just curious about that!

pedantic aside...

I have never heard railway points spoken of without the -s! Even when speaking of one, it is always "points." Or always was. In British English; I don't know about American. I wonder if it was in Indian English?

Anyway, in the face of 255 deaths, that is the most pointless point. More interested in that red light.

[itwasntme]

Originally Posted by Thad E Ginathom

There was something a red warning light that came on for five seconds. What was that about? And what's with a warning light that is going to be missed if someone is even rubbing their eyes?

Was the five-second duration a malfunction in itself, or are the staff really supposed to notice something barely more than a flash?

Totally correct! No question of being able to stop 22/24 coach configuration passenger trains at those 125-130 km/hr speeds. Even with full emergency braking, the distance required would have been 1 km. As others have pointed out, even if the Coromandel was simply 'forced' into the loop line (if that indeed was the case) at those speeds, it would have probably derailed anyway.

Scroll through this relevant Shatabdi video focusing on the faster bits. Even if the LP/ALP had suddenly seen any 'signal given and taken off', it would have been too late. That is the whole reason why we have a double caution, followed by a single caution and then a red where required.

https://youtu.be/q8m8iniNFbU