After a long & misleading murmurs of broken rail, ICF-vs-LHB coaches, deployment of Ultrasonic Rail testing Machine etc., for the first time the right and probably the most relevant point is touched upon in the reports, i.e. defect of S1 coach. Prima facie this is the most probable cause of the accident as:
(1) Complaints and reporting by several passengers of problems with S1, AC coach etc, (ignored by TTEs)
(2) Overload/Heavy load on loco just after Jhansi and blast in OHE just before derailment as reported by the driver, (ignored by...
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the controller)
(3) and report by a recently retired IR gangman that S1 was giving abnormally turbulent ride as if there was a mis alignment in the coach
(4) surprisingly very large number of deaths on derailment with especially in S1 coach in spite of derailment in flat terrain are giving indication of badly jammed wheels and/or any other defect.
Combination of the above factors make a formidable evidence.
Track may also be old which can cause derailment, but in that case loco shall not take high current and blast in OHE also shall not happen.
The phrase that the official said to driver (as reported by driver) that "jaise taise Kanpur tak le jaao", if given a little thought and properly analysed give a lot of clues into the working of IR, (which at least now has to be changed.)
(1) Ultimate complacence towards safety (it seems safety is no where in the picture)
(2) Very poor communication- What Jaise taise means (any how) for a driver. If the official had even an iota of concern for safety at that time, he should have at least given a clear message to driver to go at lower speed so that the current drawn by loco does not exceed the normal value so that at least some safety can be assured. But that could have delayed the traffic on the route and the matter would have come into the limelight of higher authorities who in turn would have demanded explanation for not getting the train checked even if stop was due at Orai about 50km ahead. Actually how much was the overload was of ultimate importance here. If the reported overload is high enough, the train has to be stopped as soon as possible and inspected/rectified before continuing normal run.
(3) Even LP also did not use his common sense and judgment,who continued blasting the train at 110kmph in overloaded condition, resulting in severe over current in OHE and consequently blast just before the accident. 110kmph speed proved too fast for the defective coach S1 which derailed very badly, surprisingly killing almost all the people in it. Even LHB coach with defects is likely to cause a high number of casualties in event of accident.
(4) At every step we see complacency and hence the accident happened. Accident usually happens when there is a series of failures/mistakes. There was enough time & opportunities between INDB and accident site to many IR personnels to take corrective action, but series of complacencies resulted ultimately in the accident. Even a single person had shown sincerity and sensibility, the accident would not have happened and precious lives would not have been lost.