It was August 1999 when the Indian Railways reported one of its deadliest accidents that killed 300 people as per official records. This tragedy forced railways to find a solution for accidents attributed to human errors or limitations and equipment failures.
The task was given to Konkan Railway, which developed the first-of-its-kind prototype of Anti-Collision Device (ACD) in just three months. Cut to 2024, the Indian Railways has finalised a version of ‘Kavach’ for installation across its network. Kavach is an indigenously developed Automatic Train Protection (ATP) system that will protect trains from collisions.
According to the railway ministry, Kavach is a highly technology intensive system that requires safety certification of the highest order. It aids the loco pilot in trains running within specified speed limits by automatic application of brakes in case the loco pilot fails to do so and also helps the train safely run during inclement weather.
“Kavach has been certified for the highest level of Safety Integrity Level (SIL) 4 by independent safety assessor and reduces the probability of train collisions in block sections and on running lines at stations through its non-SIL features,” the ministry said last month in a statement.
Last week, the Indian Railways announced that it is ready to install Kavach on 10,000 locomotives and all new projects will now have the protection system in place. Further, installation of Kavach on two high density routes — Delhi-Mumbai and Delhi-Howrah — will be completed this financial year.
In July, News18 reported about Kavach 4.0 getting approved by the Research Design and Standards Organisation (RDSO). This version covers all the major features required for the diverse railway network. This is being considered as a significant milestone in safety for Indian Railways.
The ministry has said this version of Kavach has been finalised as it is equipped to cover various terrains across the railway network – from desert to forests and from mountains to coasts and from urban to rural areas.
But all this did not happen overnight. It was a long journey for the Railways before reaching this point.
‘Raksha Kavach’
Before Kavach, the ministry had designed the ‘Raksha Kavach’ in early 2000. It was a Train Collision Prevention System (TCPS) as per the official Railway records. ‘Raksha Kavach’ was based on radio communication, microprocessors and Global Positioning System (GPS) technology. It was a Konkan Railway Corporation Limited patent technology.
In August 1999, two trains with hundreds of people on board collided at the Gaisal Station in West Bengal. The mishap killed 300 people. This incident made the railways to think of a possible solution to end the killing of people and that is how the idea of ‘Raksha Kavach’ came.
“A team of Konkan Railway in 90 days produced a prototype of the ACD that, when mounted on two approaching trains, would enable them to assess each other’s course accurately and initiate an automatic brake if they were perceived to be on collision risk,” the documents show.
As per the Konkan Railways, its technology would help in detecting and preventing a mid-section collision that could be head-on, side or rear-end collisions. It also claimed that no other technology in the world supports these features.
The technology was able to detect and generate train parting or jumbling that would bring any approaching train on the adjoining line to a dead stop.
Further, it also had a train approach warning for road users at level crossings. It was capable for detection of fouling and prevention of collision due to it.
It had manual SOS functionality available for drivers, guards and station masters to bring all trains to a halt within a radial distance of three km in emergencies.
The Konkan Railways said that an analysis of preventable and non-preventable collisions by Indian Railways concluded that out of a total of 128 train collisions that took place during the five years period between April 1997 and January 2002, about 82% cases were preventable by the ACD system. The balance 18% of the collisions were ‘non-preventable’ in any case, due to various reasons like failure of brake power of train, inadequate reaction time, insufficient braking distance.
The pilot of the ‘Raksha Kavach’ was conducted on Northeast Frontier Railways in June 2007. On 1,796 route km and across 204 stations.
But Railways Worked Further
According to Union Railway Minister Ashwini Vaishnaw and ministry documents, while the countries around the world started to have a train protection system from the 1960s onwards, India’s journey started in 1999.
As per a recent statement from the ministry, the ACD was made operational in July 2006 in West Bengal. It was a GPS-based system and “highly inaccurate”.
“There was no speed control and it did not display the signal in the driver’s cab. Further, there was no safety certification as well. ACD failed and was abandoned in 2012,” the statement reads.
Later, the Ministry developed a Train Protection and Warning System (TPWS) that was based on European Train Control System (ETCS) level 1.
It was not a radio-based system and required a lot of cabling as well. It affected operations and reduced line capacity. It was implemented on Delhi-Agra, Chennai Suburban around 2010-12 and the work completed in 2016.
Starting of Kavach
The 2012 Kakodkar Committee recommended that Indian Railways should aim for a state-of-the-art digital radio based signaling and protection system at least equivalent to ETCS level 2.
“The railways then envisaged the radio-based Train Collision Avoidance System (TCAS) or the Kavach. It was indigenous, multi-vendor, interoperable and fail-safe system,” a ministry official said, demanding anonymity.
Vaishnaw told News18 that back then tests were not conducted keeping in mind the various possible situations but that is not the case with Kavach.
“The earlier one was ACD. It was based on GPS installed in trains. The GPS were installed in the trains and the aim was to avoid collisions based on that GPS. It was installed on around 1,500 km. But unfortunately, it was not even a technology that was certified. It was uncertified and without proper testing. It was not even SIL-1. It started in 2006 but failed by 2012,” he told News18.
He further said the new Kavach was tested keeping in mind the different kinds of situations.
Speaking about the journey of Kavach, he said it started in 2014-15 with the installation of a pilot project section of 250 km on the South Central Railway — on the absolute block section of Lingampalli-Vikarabad-Wadi, Vikarabad-Bidar. After successful completion of trials, three vendors were approved for developmental orders on Indian Railways.
“In 2015-16, first field trials on passenger trains were done, while in 2017-18 Kavach specification version 3.2 was finalised. The next year, three firms were approved by RDSO for installation of the technology,” the ministry said.
As per the ministry, in July 2020, Kavach was declared as a National Automatic Train Protection System and by March 2022, it was installed on an additional 1,200 route km. As of July, Kavach has been deployed on 1,465 Route km and 144 locomotives (including Electric Multiple Unit rakes) on South Central Railway.
So far, Rs 1,216.77 crore has been spent on Kavach and the allocation of funds during the year 2024-25 stands at Rs 1,112.57 crore.
Kavach can control the speed of a train by automatic application of brakes in case the loco pilot fails to apply the brakes. It repeats line-side signals in the cab, which is useful for high speeds and foggy weather, the ministry said. It will auto whistle at level crossing gates and ensure collision avoidance by direct loco to loco communication. It also supports features of SOS in case of any mishap to control trains in the vicinity.